linux-sg2042/drivers/hid/hid-debug.c

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/*
* (c) 1999 Andreas Gal <gal@cs.uni-magdeburg.de>
* (c) 2000-2001 Vojtech Pavlik <vojtech@ucw.cz>
* (c) 2007-2009 Jiri Kosina
*
* HID debugging support
*/
/*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
* Should you need to contact me, the author, you can do so either by
* e-mail - mail your message to <vojtech@ucw.cz>, or by paper mail:
* Vojtech Pavlik, Simunkova 1594, Prague 8, 182 00 Czech Republic
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/debugfs.h>
#include <linux/seq_file.h>
#include <linux/sched.h>
#include <linux/export.h>
include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-24 16:04:11 +08:00
#include <linux/slab.h>
#include <linux/uaccess.h>
#include <linux/poll.h>
#include <linux/hid.h>
#include <linux/hid-debug.h>
static struct dentry *hid_debug_root;
struct hid_usage_entry {
unsigned page;
unsigned usage;
const char *description;
};
static const struct hid_usage_entry hid_usage_table[] = {
{ 0, 0, "Undefined" },
{ 1, 0, "GenericDesktop" },
{0, 0x01, "Pointer"},
{0, 0x02, "Mouse"},
{0, 0x04, "Joystick"},
{0, 0x05, "GamePad"},
{0, 0x06, "Keyboard"},
{0, 0x07, "Keypad"},
{0, 0x08, "MultiAxis"},
{0, 0x30, "X"},
{0, 0x31, "Y"},
{0, 0x32, "Z"},
{0, 0x33, "Rx"},
{0, 0x34, "Ry"},
{0, 0x35, "Rz"},
{0, 0x36, "Slider"},
{0, 0x37, "Dial"},
{0, 0x38, "Wheel"},
{0, 0x39, "HatSwitch"},
{0, 0x3a, "CountedBuffer"},
{0, 0x3b, "ByteCount"},
{0, 0x3c, "MotionWakeup"},
{0, 0x3d, "Start"},
{0, 0x3e, "Select"},
{0, 0x40, "Vx"},
{0, 0x41, "Vy"},
{0, 0x42, "Vz"},
{0, 0x43, "Vbrx"},
{0, 0x44, "Vbry"},
{0, 0x45, "Vbrz"},
{0, 0x46, "Vno"},
{0, 0x80, "SystemControl"},
{0, 0x81, "SystemPowerDown"},
{0, 0x82, "SystemSleep"},
{0, 0x83, "SystemWakeUp"},
{0, 0x84, "SystemContextMenu"},
{0, 0x85, "SystemMainMenu"},
{0, 0x86, "SystemAppMenu"},
{0, 0x87, "SystemMenuHelp"},
{0, 0x88, "SystemMenuExit"},
{0, 0x89, "SystemMenuSelect"},
{0, 0x8a, "SystemMenuRight"},
{0, 0x8b, "SystemMenuLeft"},
{0, 0x8c, "SystemMenuUp"},
{0, 0x8d, "SystemMenuDown"},
{0, 0x90, "D-PadUp"},
{0, 0x91, "D-PadDown"},
{0, 0x92, "D-PadRight"},
{0, 0x93, "D-PadLeft"},
{ 2, 0, "Simulation" },
{0, 0xb0, "Aileron"},
{0, 0xb1, "AileronTrim"},
{0, 0xb2, "Anti-Torque"},
{0, 0xb3, "Autopilot"},
{0, 0xb4, "Chaff"},
{0, 0xb5, "Collective"},
{0, 0xb6, "DiveBrake"},
{0, 0xb7, "ElectronicCountermeasures"},
{0, 0xb8, "Elevator"},
{0, 0xb9, "ElevatorTrim"},
{0, 0xba, "Rudder"},
{0, 0xbb, "Throttle"},
{0, 0xbc, "FlightCommunications"},
{0, 0xbd, "FlareRelease"},
{0, 0xbe, "LandingGear"},
{0, 0xbf, "ToeBrake"},
{ 6, 0, "GenericDeviceControls" },
{0, 0x20, "BatteryStrength" },
{0, 0x21, "WirelessChannel" },
{0, 0x22, "WirelessID" },
{0, 0x23, "DiscoverWirelessControl" },
{0, 0x24, "SecurityCodeCharacterEntered" },
{0, 0x25, "SecurityCodeCharactedErased" },
{0, 0x26, "SecurityCodeCleared" },
{ 7, 0, "Keyboard" },
{ 8, 0, "LED" },
{0, 0x01, "NumLock"},
{0, 0x02, "CapsLock"},
{0, 0x03, "ScrollLock"},
{0, 0x04, "Compose"},
{0, 0x05, "Kana"},
{0, 0x4b, "GenericIndicator"},
{ 9, 0, "Button" },
{ 10, 0, "Ordinal" },
{ 12, 0, "Consumer" },
{0, 0x238, "HorizontalWheel"},
{ 13, 0, "Digitizers" },
{0, 0x01, "Digitizer"},
{0, 0x02, "Pen"},
{0, 0x03, "LightPen"},
{0, 0x04, "TouchScreen"},
{0, 0x05, "TouchPad"},
{0, 0x20, "Stylus"},
{0, 0x21, "Puck"},
{0, 0x22, "Finger"},
{0, 0x30, "TipPressure"},
{0, 0x31, "BarrelPressure"},
{0, 0x32, "InRange"},
{0, 0x33, "Touch"},
{0, 0x34, "UnTouch"},
{0, 0x35, "Tap"},
{0, 0x39, "TabletFunctionKey"},
{0, 0x3a, "ProgramChangeKey"},
{0, 0x3c, "Invert"},
{0, 0x42, "TipSwitch"},
{0, 0x43, "SecondaryTipSwitch"},
{0, 0x44, "BarrelSwitch"},
{0, 0x45, "Eraser"},
{0, 0x46, "TabletPick"},
{0, 0x47, "Confidence"},
{0, 0x48, "Width"},
{0, 0x49, "Height"},
{0, 0x51, "ContactID"},
{0, 0x52, "InputMode"},
{0, 0x53, "DeviceIndex"},
{0, 0x54, "ContactCount"},
{0, 0x55, "ContactMaximumNumber"},
{ 15, 0, "PhysicalInterfaceDevice" },
{0, 0x00, "Undefined"},
{0, 0x01, "Physical_Interface_Device"},
{0, 0x20, "Normal"},
{0, 0x21, "Set_Effect_Report"},
{0, 0x22, "Effect_Block_Index"},
{0, 0x23, "Parameter_Block_Offset"},
{0, 0x24, "ROM_Flag"},
{0, 0x25, "Effect_Type"},
{0, 0x26, "ET_Constant_Force"},
{0, 0x27, "ET_Ramp"},
{0, 0x28, "ET_Custom_Force_Data"},
{0, 0x30, "ET_Square"},
{0, 0x31, "ET_Sine"},
{0, 0x32, "ET_Triangle"},
{0, 0x33, "ET_Sawtooth_Up"},
{0, 0x34, "ET_Sawtooth_Down"},
{0, 0x40, "ET_Spring"},
{0, 0x41, "ET_Damper"},
{0, 0x42, "ET_Inertia"},
{0, 0x43, "ET_Friction"},
{0, 0x50, "Duration"},
{0, 0x51, "Sample_Period"},
{0, 0x52, "Gain"},
{0, 0x53, "Trigger_Button"},
{0, 0x54, "Trigger_Repeat_Interval"},
{0, 0x55, "Axes_Enable"},
{0, 0x56, "Direction_Enable"},
{0, 0x57, "Direction"},
{0, 0x58, "Type_Specific_Block_Offset"},
{0, 0x59, "Block_Type"},
{0, 0x5A, "Set_Envelope_Report"},
{0, 0x5B, "Attack_Level"},
{0, 0x5C, "Attack_Time"},
{0, 0x5D, "Fade_Level"},
{0, 0x5E, "Fade_Time"},
{0, 0x5F, "Set_Condition_Report"},
{0, 0x60, "CP_Offset"},
{0, 0x61, "Positive_Coefficient"},
{0, 0x62, "Negative_Coefficient"},
{0, 0x63, "Positive_Saturation"},
{0, 0x64, "Negative_Saturation"},
{0, 0x65, "Dead_Band"},
{0, 0x66, "Download_Force_Sample"},
{0, 0x67, "Isoch_Custom_Force_Enable"},
{0, 0x68, "Custom_Force_Data_Report"},
{0, 0x69, "Custom_Force_Data"},
{0, 0x6A, "Custom_Force_Vendor_Defined_Data"},
{0, 0x6B, "Set_Custom_Force_Report"},
{0, 0x6C, "Custom_Force_Data_Offset"},
{0, 0x6D, "Sample_Count"},
{0, 0x6E, "Set_Periodic_Report"},
{0, 0x6F, "Offset"},
{0, 0x70, "Magnitude"},
{0, 0x71, "Phase"},
{0, 0x72, "Period"},
{0, 0x73, "Set_Constant_Force_Report"},
{0, 0x74, "Set_Ramp_Force_Report"},
{0, 0x75, "Ramp_Start"},
{0, 0x76, "Ramp_End"},
{0, 0x77, "Effect_Operation_Report"},
{0, 0x78, "Effect_Operation"},
{0, 0x79, "Op_Effect_Start"},
{0, 0x7A, "Op_Effect_Start_Solo"},
{0, 0x7B, "Op_Effect_Stop"},
{0, 0x7C, "Loop_Count"},
{0, 0x7D, "Device_Gain_Report"},
{0, 0x7E, "Device_Gain"},
{0, 0x7F, "PID_Pool_Report"},
{0, 0x80, "RAM_Pool_Size"},
{0, 0x81, "ROM_Pool_Size"},
{0, 0x82, "ROM_Effect_Block_Count"},
{0, 0x83, "Simultaneous_Effects_Max"},
{0, 0x84, "Pool_Alignment"},
{0, 0x85, "PID_Pool_Move_Report"},
{0, 0x86, "Move_Source"},
{0, 0x87, "Move_Destination"},
{0, 0x88, "Move_Length"},
{0, 0x89, "PID_Block_Load_Report"},
{0, 0x8B, "Block_Load_Status"},
{0, 0x8C, "Block_Load_Success"},
{0, 0x8D, "Block_Load_Full"},
{0, 0x8E, "Block_Load_Error"},
{0, 0x8F, "Block_Handle"},
{0, 0x90, "PID_Block_Free_Report"},
{0, 0x91, "Type_Specific_Block_Handle"},
{0, 0x92, "PID_State_Report"},
{0, 0x94, "Effect_Playing"},
{0, 0x95, "PID_Device_Control_Report"},
{0, 0x96, "PID_Device_Control"},
{0, 0x97, "DC_Enable_Actuators"},
{0, 0x98, "DC_Disable_Actuators"},
{0, 0x99, "DC_Stop_All_Effects"},
{0, 0x9A, "DC_Device_Reset"},
{0, 0x9B, "DC_Device_Pause"},
{0, 0x9C, "DC_Device_Continue"},
{0, 0x9F, "Device_Paused"},
{0, 0xA0, "Actuators_Enabled"},
{0, 0xA4, "Safety_Switch"},
{0, 0xA5, "Actuator_Override_Switch"},
{0, 0xA6, "Actuator_Power"},
{0, 0xA7, "Start_Delay"},
{0, 0xA8, "Parameter_Block_Size"},
{0, 0xA9, "Device_Managed_Pool"},
{0, 0xAA, "Shared_Parameter_Blocks"},
{0, 0xAB, "Create_New_Effect_Report"},
{0, 0xAC, "RAM_Pool_Available"},
{ 0x84, 0, "Power Device" },
{ 0x84, 0x02, "PresentStatus" },
{ 0x84, 0x03, "ChangeStatus" },
{ 0x84, 0x04, "UPS" },
{ 0x84, 0x05, "PowerSupply" },
{ 0x84, 0x10, "BatterySystem" },
{ 0x84, 0x11, "BatterySystemID" },
{ 0x84, 0x12, "Battery" },
{ 0x84, 0x13, "BatteryID" },
{ 0x84, 0x14, "Charger" },
{ 0x84, 0x15, "ChargerID" },
{ 0x84, 0x16, "PowerConverter" },
{ 0x84, 0x17, "PowerConverterID" },
{ 0x84, 0x18, "OutletSystem" },
{ 0x84, 0x19, "OutletSystemID" },
{ 0x84, 0x1a, "Input" },
{ 0x84, 0x1b, "InputID" },
{ 0x84, 0x1c, "Output" },
{ 0x84, 0x1d, "OutputID" },
{ 0x84, 0x1e, "Flow" },
{ 0x84, 0x1f, "FlowID" },
{ 0x84, 0x20, "Outlet" },
{ 0x84, 0x21, "OutletID" },
{ 0x84, 0x22, "Gang" },
{ 0x84, 0x24, "PowerSummary" },
{ 0x84, 0x25, "PowerSummaryID" },
{ 0x84, 0x30, "Voltage" },
{ 0x84, 0x31, "Current" },
{ 0x84, 0x32, "Frequency" },
{ 0x84, 0x33, "ApparentPower" },
{ 0x84, 0x35, "PercentLoad" },
{ 0x84, 0x40, "ConfigVoltage" },
{ 0x84, 0x41, "ConfigCurrent" },
{ 0x84, 0x43, "ConfigApparentPower" },
{ 0x84, 0x53, "LowVoltageTransfer" },
{ 0x84, 0x54, "HighVoltageTransfer" },
{ 0x84, 0x56, "DelayBeforeStartup" },
{ 0x84, 0x57, "DelayBeforeShutdown" },
{ 0x84, 0x58, "Test" },
{ 0x84, 0x5a, "AudibleAlarmControl" },
{ 0x84, 0x60, "Present" },
{ 0x84, 0x61, "Good" },
{ 0x84, 0x62, "InternalFailure" },
{ 0x84, 0x65, "Overload" },
{ 0x84, 0x66, "OverCharged" },
{ 0x84, 0x67, "OverTemperature" },
{ 0x84, 0x68, "ShutdownRequested" },
{ 0x84, 0x69, "ShutdownImminent" },
{ 0x84, 0x6b, "SwitchOn/Off" },
{ 0x84, 0x6c, "Switchable" },
{ 0x84, 0x6d, "Used" },
{ 0x84, 0x6e, "Boost" },
{ 0x84, 0x73, "CommunicationLost" },
{ 0x84, 0xfd, "iManufacturer" },
{ 0x84, 0xfe, "iProduct" },
{ 0x84, 0xff, "iSerialNumber" },
{ 0x85, 0, "Battery System" },
{ 0x85, 0x01, "SMBBatteryMode" },
{ 0x85, 0x02, "SMBBatteryStatus" },
{ 0x85, 0x03, "SMBAlarmWarning" },
{ 0x85, 0x04, "SMBChargerMode" },
{ 0x85, 0x05, "SMBChargerStatus" },
{ 0x85, 0x06, "SMBChargerSpecInfo" },
{ 0x85, 0x07, "SMBSelectorState" },
{ 0x85, 0x08, "SMBSelectorPresets" },
{ 0x85, 0x09, "SMBSelectorInfo" },
{ 0x85, 0x29, "RemainingCapacityLimit" },
{ 0x85, 0x2c, "CapacityMode" },
{ 0x85, 0x42, "BelowRemainingCapacityLimit" },
{ 0x85, 0x44, "Charging" },
{ 0x85, 0x45, "Discharging" },
{ 0x85, 0x4b, "NeedReplacement" },
{ 0x85, 0x66, "RemainingCapacity" },
{ 0x85, 0x68, "RunTimeToEmpty" },
{ 0x85, 0x6a, "AverageTimeToFull" },
{ 0x85, 0x83, "DesignCapacity" },
{ 0x85, 0x85, "ManufacturerDate" },
{ 0x85, 0x89, "iDeviceChemistry" },
{ 0x85, 0x8b, "Rechargeable" },
{ 0x85, 0x8f, "iOEMInformation" },
{ 0x85, 0x8d, "CapacityGranularity1" },
{ 0x85, 0xd0, "ACPresent" },
/* pages 0xff00 to 0xffff are vendor-specific */
{ 0xffff, 0, "Vendor-specific-FF" },
{ 0, 0, NULL }
};
/* Either output directly into simple seq_file, or (if f == NULL)
* allocate a separate buffer that will then be passed to the 'events'
* ringbuffer.
*
* This is because these functions can be called both for "one-shot"
* "rdesc" while resolving, or for blocking "events".
*
* This holds both for resolv_usage_page() and hid_resolv_usage().
*/
static char *resolv_usage_page(unsigned page, struct seq_file *f) {
const struct hid_usage_entry *p;
char *buf = NULL;
if (!f) {
buf = kzalloc(sizeof(char) * HID_DEBUG_BUFSIZE, GFP_ATOMIC);
if (!buf)
return ERR_PTR(-ENOMEM);
}
for (p = hid_usage_table; p->description; p++)
if (p->page == page) {
if (!f) {
snprintf(buf, HID_DEBUG_BUFSIZE, "%s",
p->description);
return buf;
}
else {
seq_printf(f, "%s", p->description);
return NULL;
}
}
if (!f)
snprintf(buf, HID_DEBUG_BUFSIZE, "%04x", page);
else
seq_printf(f, "%04x", page);
return buf;
}
char *hid_resolv_usage(unsigned usage, struct seq_file *f) {
const struct hid_usage_entry *p;
char *buf = NULL;
int len = 0;
buf = resolv_usage_page(usage >> 16, f);
if (IS_ERR(buf)) {
pr_err("error allocating HID debug buffer\n");
return NULL;
}
if (!f) {
len = strlen(buf);
snprintf(buf+len, max(0, HID_DEBUG_BUFSIZE - len), ".");
len++;
}
else {
seq_printf(f, ".");
}
for (p = hid_usage_table; p->description; p++)
if (p->page == (usage >> 16)) {
for(++p; p->description && p->usage != 0; p++)
if (p->usage == (usage & 0xffff)) {
if (!f)
snprintf(buf + len,
max(0,HID_DEBUG_BUFSIZE - len - 1),
"%s", p->description);
else
seq_printf(f,
"%s",
p->description);
return buf;
}
break;
}
if (!f)
snprintf(buf + len, max(0, HID_DEBUG_BUFSIZE - len - 1),
"%04x", usage & 0xffff);
else
seq_printf(f, "%04x", usage & 0xffff);
return buf;
}
EXPORT_SYMBOL_GPL(hid_resolv_usage);
static void tab(int n, struct seq_file *f) {
seq_printf(f, "%*s", n, "");
}
void hid_dump_field(struct hid_field *field, int n, struct seq_file *f) {
int j;
if (field->physical) {
tab(n, f);
seq_printf(f, "Physical(");
hid_resolv_usage(field->physical, f); seq_printf(f, ")\n");
}
if (field->logical) {
tab(n, f);
seq_printf(f, "Logical(");
hid_resolv_usage(field->logical, f); seq_printf(f, ")\n");
}
if (field->application) {
tab(n, f);
seq_printf(f, "Application(");
hid_resolv_usage(field->application, f); seq_printf(f, ")\n");
}
tab(n, f); seq_printf(f, "Usage(%d)\n", field->maxusage);
for (j = 0; j < field->maxusage; j++) {
tab(n+2, f); hid_resolv_usage(field->usage[j].hid, f); seq_printf(f, "\n");
}
if (field->logical_minimum != field->logical_maximum) {
tab(n, f); seq_printf(f, "Logical Minimum(%d)\n", field->logical_minimum);
tab(n, f); seq_printf(f, "Logical Maximum(%d)\n", field->logical_maximum);
}
if (field->physical_minimum != field->physical_maximum) {
tab(n, f); seq_printf(f, "Physical Minimum(%d)\n", field->physical_minimum);
tab(n, f); seq_printf(f, "Physical Maximum(%d)\n", field->physical_maximum);
}
if (field->unit_exponent) {
tab(n, f); seq_printf(f, "Unit Exponent(%d)\n", field->unit_exponent);
}
if (field->unit) {
static const char *systems[5] = { "None", "SI Linear", "SI Rotation", "English Linear", "English Rotation" };
static const char *units[5][8] = {
{ "None", "None", "None", "None", "None", "None", "None", "None" },
{ "None", "Centimeter", "Gram", "Seconds", "Kelvin", "Ampere", "Candela", "None" },
{ "None", "Radians", "Gram", "Seconds", "Kelvin", "Ampere", "Candela", "None" },
{ "None", "Inch", "Slug", "Seconds", "Fahrenheit", "Ampere", "Candela", "None" },
{ "None", "Degrees", "Slug", "Seconds", "Fahrenheit", "Ampere", "Candela", "None" }
};
int i;
int sys;
__u32 data = field->unit;
/* First nibble tells us which system we're in. */
sys = data & 0xf;
data >>= 4;
if(sys > 4) {
tab(n, f); seq_printf(f, "Unit(Invalid)\n");
}
else {
int earlier_unit = 0;
tab(n, f); seq_printf(f, "Unit(%s : ", systems[sys]);
for (i=1 ; i<sizeof(__u32)*2 ; i++) {
char nibble = data & 0xf;
data >>= 4;
if (nibble != 0) {
if(earlier_unit++ > 0)
seq_printf(f, "*");
seq_printf(f, "%s", units[sys][i]);
if(nibble != 1) {
/* This is a _signed_ nibble(!) */
int val = nibble & 0x7;
if(nibble & 0x08)
val = -((0x7 & ~val) +1);
seq_printf(f, "^%d", val);
}
}
}
seq_printf(f, ")\n");
}
}
tab(n, f); seq_printf(f, "Report Size(%u)\n", field->report_size);
tab(n, f); seq_printf(f, "Report Count(%u)\n", field->report_count);
tab(n, f); seq_printf(f, "Report Offset(%u)\n", field->report_offset);
tab(n, f); seq_printf(f, "Flags( ");
j = field->flags;
seq_printf(f, "%s", HID_MAIN_ITEM_CONSTANT & j ? "Constant " : "");
seq_printf(f, "%s", HID_MAIN_ITEM_VARIABLE & j ? "Variable " : "Array ");
seq_printf(f, "%s", HID_MAIN_ITEM_RELATIVE & j ? "Relative " : "Absolute ");
seq_printf(f, "%s", HID_MAIN_ITEM_WRAP & j ? "Wrap " : "");
seq_printf(f, "%s", HID_MAIN_ITEM_NONLINEAR & j ? "NonLinear " : "");
seq_printf(f, "%s", HID_MAIN_ITEM_NO_PREFERRED & j ? "NoPreferredState " : "");
seq_printf(f, "%s", HID_MAIN_ITEM_NULL_STATE & j ? "NullState " : "");
seq_printf(f, "%s", HID_MAIN_ITEM_VOLATILE & j ? "Volatile " : "");
seq_printf(f, "%s", HID_MAIN_ITEM_BUFFERED_BYTE & j ? "BufferedByte " : "");
seq_printf(f, ")\n");
}
EXPORT_SYMBOL_GPL(hid_dump_field);
void hid_dump_device(struct hid_device *device, struct seq_file *f)
{
struct hid_report_enum *report_enum;
struct hid_report *report;
struct list_head *list;
unsigned i,k;
static const char *table[] = {"INPUT", "OUTPUT", "FEATURE"};
for (i = 0; i < HID_REPORT_TYPES; i++) {
report_enum = device->report_enum + i;
list = report_enum->report_list.next;
while (list != &report_enum->report_list) {
report = (struct hid_report *) list;
tab(2, f);
seq_printf(f, "%s", table[i]);
if (report->id)
seq_printf(f, "(%d)", report->id);
seq_printf(f, "[%s]", table[report->type]);
seq_printf(f, "\n");
for (k = 0; k < report->maxfield; k++) {
tab(4, f);
seq_printf(f, "Field(%d)\n", k);
hid_dump_field(report->field[k], 6, f);
}
list = list->next;
}
}
}
EXPORT_SYMBOL_GPL(hid_dump_device);
/* enqueue string to 'events' ring buffer */
void hid_debug_event(struct hid_device *hdev, char *buf)
{
int i;
struct hid_debug_list *list;
HID: debug: fix RCU preemption issue Commit 2353f2bea ("HID: protect hid_debug_list") introduced mutex locking around debug_list access to prevent SMP races when debugfs nodes are being operated upon by multiple userspace processess. mutex is not a proper synchronization primitive though, as the hid-debug callbacks are being called from atomic contexts. We also have to be careful about disabling IRQs when taking the lock to prevent deadlock against IRQ handlers. Benjamin reports this has also been reported in RH bugzilla as bug #958935. =============================== [ INFO: suspicious RCU usage. ] 3.9.0+ #94 Not tainted ------------------------------- include/linux/rcupdate.h:476 Illegal context switch in RCU read-side critical section! other info that might help us debug this: rcu_scheduler_active = 1, debug_locks = 0 4 locks held by Xorg/5502: #0: (&evdev->mutex){+.+...}, at: [<ffffffff81512c3d>] evdev_write+0x6d/0x160 #1: (&(&dev->event_lock)->rlock#2){-.-...}, at: [<ffffffff8150dd9b>] input_inject_event+0x5b/0x230 #2: (rcu_read_lock){.+.+..}, at: [<ffffffff8150dd82>] input_inject_event+0x42/0x230 #3: (&(&usbhid->lock)->rlock){-.....}, at: [<ffffffff81565289>] usb_hidinput_input_event+0x89/0x120 stack backtrace: CPU: 0 PID: 5502 Comm: Xorg Not tainted 3.9.0+ #94 Hardware name: Dell Inc. OptiPlex 390/0M5DCD, BIOS A09 07/24/2012 0000000000000001 ffff8800689c7c38 ffffffff816f249f ffff8800689c7c68 ffffffff810acb1d 0000000000000000 ffffffff81a03ac7 000000000000019d 0000000000000000 ffff8800689c7c90 ffffffff8107cda7 0000000000000000 Call Trace: [<ffffffff816f249f>] dump_stack+0x19/0x1b [<ffffffff810acb1d>] lockdep_rcu_suspicious+0xfd/0x130 [<ffffffff8107cda7>] __might_sleep+0xc7/0x230 [<ffffffff816f7770>] mutex_lock_nested+0x40/0x3a0 [<ffffffff81312ac4>] ? vsnprintf+0x354/0x640 [<ffffffff81553cc4>] hid_debug_event+0x34/0x100 [<ffffffff81554197>] hid_dump_input+0x67/0xa0 [<ffffffff81556430>] hid_set_field+0x50/0x120 [<ffffffff8156529a>] usb_hidinput_input_event+0x9a/0x120 [<ffffffff8150d89e>] input_handle_event+0x8e/0x530 [<ffffffff8150df10>] input_inject_event+0x1d0/0x230 [<ffffffff8150dd82>] ? input_inject_event+0x42/0x230 [<ffffffff81512cae>] evdev_write+0xde/0x160 [<ffffffff81185038>] vfs_write+0xc8/0x1f0 [<ffffffff81185535>] SyS_write+0x55/0xa0 [<ffffffff81704482>] system_call_fastpath+0x16/0x1b BUG: sleeping function called from invalid context at kernel/mutex.c:413 in_atomic(): 1, irqs_disabled(): 1, pid: 5502, name: Xorg INFO: lockdep is turned off. irq event stamp: 1098574 hardirqs last enabled at (1098573): [<ffffffff816fb53f>] _raw_spin_unlock_irqrestore+0x3f/0x70 hardirqs last disabled at (1098574): [<ffffffff816faaf5>] _raw_spin_lock_irqsave+0x25/0xa0 softirqs last enabled at (1098306): [<ffffffff8104971f>] __do_softirq+0x18f/0x3c0 softirqs last disabled at (1097867): [<ffffffff81049ad5>] irq_exit+0xa5/0xb0 CPU: 0 PID: 5502 Comm: Xorg Not tainted 3.9.0+ #94 Hardware name: Dell Inc. OptiPlex 390/0M5DCD, BIOS A09 07/24/2012 ffffffff81a03ac7 ffff8800689c7c68 ffffffff816f249f ffff8800689c7c90 ffffffff8107ce60 0000000000000000 ffff8800689c7fd8 ffff88006a62c800 ffff8800689c7d10 ffffffff816f7770 ffff8800689c7d00 ffffffff81312ac4 Call Trace: [<ffffffff816f249f>] dump_stack+0x19/0x1b [<ffffffff8107ce60>] __might_sleep+0x180/0x230 [<ffffffff816f7770>] mutex_lock_nested+0x40/0x3a0 [<ffffffff81312ac4>] ? vsnprintf+0x354/0x640 [<ffffffff81553cc4>] hid_debug_event+0x34/0x100 [<ffffffff81554197>] hid_dump_input+0x67/0xa0 [<ffffffff81556430>] hid_set_field+0x50/0x120 [<ffffffff8156529a>] usb_hidinput_input_event+0x9a/0x120 [<ffffffff8150d89e>] input_handle_event+0x8e/0x530 [<ffffffff8150df10>] input_inject_event+0x1d0/0x230 [<ffffffff8150dd82>] ? input_inject_event+0x42/0x230 [<ffffffff81512cae>] evdev_write+0xde/0x160 [<ffffffff81185038>] vfs_write+0xc8/0x1f0 [<ffffffff81185535>] SyS_write+0x55/0xa0 [<ffffffff81704482>] system_call_fastpath+0x16/0x1b Reported-by: majianpeng <majianpeng@gmail.com> Reported-by: Benjamin Tissoires <benjamin.tissoires@gmail.com> Reviewed-by: Dmitry Torokhov <dmitry.torokhov@gmail.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2013-05-06 19:05:50 +08:00
unsigned long flags;
HID: debug: fix RCU preemption issue Commit 2353f2bea ("HID: protect hid_debug_list") introduced mutex locking around debug_list access to prevent SMP races when debugfs nodes are being operated upon by multiple userspace processess. mutex is not a proper synchronization primitive though, as the hid-debug callbacks are being called from atomic contexts. We also have to be careful about disabling IRQs when taking the lock to prevent deadlock against IRQ handlers. Benjamin reports this has also been reported in RH bugzilla as bug #958935. =============================== [ INFO: suspicious RCU usage. ] 3.9.0+ #94 Not tainted ------------------------------- include/linux/rcupdate.h:476 Illegal context switch in RCU read-side critical section! other info that might help us debug this: rcu_scheduler_active = 1, debug_locks = 0 4 locks held by Xorg/5502: #0: (&evdev->mutex){+.+...}, at: [<ffffffff81512c3d>] evdev_write+0x6d/0x160 #1: (&(&dev->event_lock)->rlock#2){-.-...}, at: [<ffffffff8150dd9b>] input_inject_event+0x5b/0x230 #2: (rcu_read_lock){.+.+..}, at: [<ffffffff8150dd82>] input_inject_event+0x42/0x230 #3: (&(&usbhid->lock)->rlock){-.....}, at: [<ffffffff81565289>] usb_hidinput_input_event+0x89/0x120 stack backtrace: CPU: 0 PID: 5502 Comm: Xorg Not tainted 3.9.0+ #94 Hardware name: Dell Inc. OptiPlex 390/0M5DCD, BIOS A09 07/24/2012 0000000000000001 ffff8800689c7c38 ffffffff816f249f ffff8800689c7c68 ffffffff810acb1d 0000000000000000 ffffffff81a03ac7 000000000000019d 0000000000000000 ffff8800689c7c90 ffffffff8107cda7 0000000000000000 Call Trace: [<ffffffff816f249f>] dump_stack+0x19/0x1b [<ffffffff810acb1d>] lockdep_rcu_suspicious+0xfd/0x130 [<ffffffff8107cda7>] __might_sleep+0xc7/0x230 [<ffffffff816f7770>] mutex_lock_nested+0x40/0x3a0 [<ffffffff81312ac4>] ? vsnprintf+0x354/0x640 [<ffffffff81553cc4>] hid_debug_event+0x34/0x100 [<ffffffff81554197>] hid_dump_input+0x67/0xa0 [<ffffffff81556430>] hid_set_field+0x50/0x120 [<ffffffff8156529a>] usb_hidinput_input_event+0x9a/0x120 [<ffffffff8150d89e>] input_handle_event+0x8e/0x530 [<ffffffff8150df10>] input_inject_event+0x1d0/0x230 [<ffffffff8150dd82>] ? input_inject_event+0x42/0x230 [<ffffffff81512cae>] evdev_write+0xde/0x160 [<ffffffff81185038>] vfs_write+0xc8/0x1f0 [<ffffffff81185535>] SyS_write+0x55/0xa0 [<ffffffff81704482>] system_call_fastpath+0x16/0x1b BUG: sleeping function called from invalid context at kernel/mutex.c:413 in_atomic(): 1, irqs_disabled(): 1, pid: 5502, name: Xorg INFO: lockdep is turned off. irq event stamp: 1098574 hardirqs last enabled at (1098573): [<ffffffff816fb53f>] _raw_spin_unlock_irqrestore+0x3f/0x70 hardirqs last disabled at (1098574): [<ffffffff816faaf5>] _raw_spin_lock_irqsave+0x25/0xa0 softirqs last enabled at (1098306): [<ffffffff8104971f>] __do_softirq+0x18f/0x3c0 softirqs last disabled at (1097867): [<ffffffff81049ad5>] irq_exit+0xa5/0xb0 CPU: 0 PID: 5502 Comm: Xorg Not tainted 3.9.0+ #94 Hardware name: Dell Inc. OptiPlex 390/0M5DCD, BIOS A09 07/24/2012 ffffffff81a03ac7 ffff8800689c7c68 ffffffff816f249f ffff8800689c7c90 ffffffff8107ce60 0000000000000000 ffff8800689c7fd8 ffff88006a62c800 ffff8800689c7d10 ffffffff816f7770 ffff8800689c7d00 ffffffff81312ac4 Call Trace: [<ffffffff816f249f>] dump_stack+0x19/0x1b [<ffffffff8107ce60>] __might_sleep+0x180/0x230 [<ffffffff816f7770>] mutex_lock_nested+0x40/0x3a0 [<ffffffff81312ac4>] ? vsnprintf+0x354/0x640 [<ffffffff81553cc4>] hid_debug_event+0x34/0x100 [<ffffffff81554197>] hid_dump_input+0x67/0xa0 [<ffffffff81556430>] hid_set_field+0x50/0x120 [<ffffffff8156529a>] usb_hidinput_input_event+0x9a/0x120 [<ffffffff8150d89e>] input_handle_event+0x8e/0x530 [<ffffffff8150df10>] input_inject_event+0x1d0/0x230 [<ffffffff8150dd82>] ? input_inject_event+0x42/0x230 [<ffffffff81512cae>] evdev_write+0xde/0x160 [<ffffffff81185038>] vfs_write+0xc8/0x1f0 [<ffffffff81185535>] SyS_write+0x55/0xa0 [<ffffffff81704482>] system_call_fastpath+0x16/0x1b Reported-by: majianpeng <majianpeng@gmail.com> Reported-by: Benjamin Tissoires <benjamin.tissoires@gmail.com> Reviewed-by: Dmitry Torokhov <dmitry.torokhov@gmail.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2013-05-06 19:05:50 +08:00
spin_lock_irqsave(&hdev->debug_list_lock, flags);
list_for_each_entry(list, &hdev->debug_list, node) {
for (i = 0; i < strlen(buf); i++)
list->hid_debug_buf[(list->tail + i) % HID_DEBUG_BUFSIZE] =
buf[i];
list->tail = (list->tail + i) % HID_DEBUG_BUFSIZE;
}
HID: debug: fix RCU preemption issue Commit 2353f2bea ("HID: protect hid_debug_list") introduced mutex locking around debug_list access to prevent SMP races when debugfs nodes are being operated upon by multiple userspace processess. mutex is not a proper synchronization primitive though, as the hid-debug callbacks are being called from atomic contexts. We also have to be careful about disabling IRQs when taking the lock to prevent deadlock against IRQ handlers. Benjamin reports this has also been reported in RH bugzilla as bug #958935. =============================== [ INFO: suspicious RCU usage. ] 3.9.0+ #94 Not tainted ------------------------------- include/linux/rcupdate.h:476 Illegal context switch in RCU read-side critical section! other info that might help us debug this: rcu_scheduler_active = 1, debug_locks = 0 4 locks held by Xorg/5502: #0: (&evdev->mutex){+.+...}, at: [<ffffffff81512c3d>] evdev_write+0x6d/0x160 #1: (&(&dev->event_lock)->rlock#2){-.-...}, at: [<ffffffff8150dd9b>] input_inject_event+0x5b/0x230 #2: (rcu_read_lock){.+.+..}, at: [<ffffffff8150dd82>] input_inject_event+0x42/0x230 #3: (&(&usbhid->lock)->rlock){-.....}, at: [<ffffffff81565289>] usb_hidinput_input_event+0x89/0x120 stack backtrace: CPU: 0 PID: 5502 Comm: Xorg Not tainted 3.9.0+ #94 Hardware name: Dell Inc. OptiPlex 390/0M5DCD, BIOS A09 07/24/2012 0000000000000001 ffff8800689c7c38 ffffffff816f249f ffff8800689c7c68 ffffffff810acb1d 0000000000000000 ffffffff81a03ac7 000000000000019d 0000000000000000 ffff8800689c7c90 ffffffff8107cda7 0000000000000000 Call Trace: [<ffffffff816f249f>] dump_stack+0x19/0x1b [<ffffffff810acb1d>] lockdep_rcu_suspicious+0xfd/0x130 [<ffffffff8107cda7>] __might_sleep+0xc7/0x230 [<ffffffff816f7770>] mutex_lock_nested+0x40/0x3a0 [<ffffffff81312ac4>] ? vsnprintf+0x354/0x640 [<ffffffff81553cc4>] hid_debug_event+0x34/0x100 [<ffffffff81554197>] hid_dump_input+0x67/0xa0 [<ffffffff81556430>] hid_set_field+0x50/0x120 [<ffffffff8156529a>] usb_hidinput_input_event+0x9a/0x120 [<ffffffff8150d89e>] input_handle_event+0x8e/0x530 [<ffffffff8150df10>] input_inject_event+0x1d0/0x230 [<ffffffff8150dd82>] ? input_inject_event+0x42/0x230 [<ffffffff81512cae>] evdev_write+0xde/0x160 [<ffffffff81185038>] vfs_write+0xc8/0x1f0 [<ffffffff81185535>] SyS_write+0x55/0xa0 [<ffffffff81704482>] system_call_fastpath+0x16/0x1b BUG: sleeping function called from invalid context at kernel/mutex.c:413 in_atomic(): 1, irqs_disabled(): 1, pid: 5502, name: Xorg INFO: lockdep is turned off. irq event stamp: 1098574 hardirqs last enabled at (1098573): [<ffffffff816fb53f>] _raw_spin_unlock_irqrestore+0x3f/0x70 hardirqs last disabled at (1098574): [<ffffffff816faaf5>] _raw_spin_lock_irqsave+0x25/0xa0 softirqs last enabled at (1098306): [<ffffffff8104971f>] __do_softirq+0x18f/0x3c0 softirqs last disabled at (1097867): [<ffffffff81049ad5>] irq_exit+0xa5/0xb0 CPU: 0 PID: 5502 Comm: Xorg Not tainted 3.9.0+ #94 Hardware name: Dell Inc. OptiPlex 390/0M5DCD, BIOS A09 07/24/2012 ffffffff81a03ac7 ffff8800689c7c68 ffffffff816f249f ffff8800689c7c90 ffffffff8107ce60 0000000000000000 ffff8800689c7fd8 ffff88006a62c800 ffff8800689c7d10 ffffffff816f7770 ffff8800689c7d00 ffffffff81312ac4 Call Trace: [<ffffffff816f249f>] dump_stack+0x19/0x1b [<ffffffff8107ce60>] __might_sleep+0x180/0x230 [<ffffffff816f7770>] mutex_lock_nested+0x40/0x3a0 [<ffffffff81312ac4>] ? vsnprintf+0x354/0x640 [<ffffffff81553cc4>] hid_debug_event+0x34/0x100 [<ffffffff81554197>] hid_dump_input+0x67/0xa0 [<ffffffff81556430>] hid_set_field+0x50/0x120 [<ffffffff8156529a>] usb_hidinput_input_event+0x9a/0x120 [<ffffffff8150d89e>] input_handle_event+0x8e/0x530 [<ffffffff8150df10>] input_inject_event+0x1d0/0x230 [<ffffffff8150dd82>] ? input_inject_event+0x42/0x230 [<ffffffff81512cae>] evdev_write+0xde/0x160 [<ffffffff81185038>] vfs_write+0xc8/0x1f0 [<ffffffff81185535>] SyS_write+0x55/0xa0 [<ffffffff81704482>] system_call_fastpath+0x16/0x1b Reported-by: majianpeng <majianpeng@gmail.com> Reported-by: Benjamin Tissoires <benjamin.tissoires@gmail.com> Reviewed-by: Dmitry Torokhov <dmitry.torokhov@gmail.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2013-05-06 19:05:50 +08:00
spin_unlock_irqrestore(&hdev->debug_list_lock, flags);
wake_up_interruptible(&hdev->debug_wait);
}
EXPORT_SYMBOL_GPL(hid_debug_event);
void hid_dump_report(struct hid_device *hid, int type, u8 *data,
int size)
{
struct hid_report_enum *report_enum;
char *buf;
unsigned int i;
buf = kmalloc(sizeof(char) * HID_DEBUG_BUFSIZE, GFP_ATOMIC);
if (!buf)
return;
report_enum = hid->report_enum + type;
/* dump the report */
snprintf(buf, HID_DEBUG_BUFSIZE - 1,
"\nreport (size %u) (%snumbered) = ", size,
report_enum->numbered ? "" : "un");
hid_debug_event(hid, buf);
for (i = 0; i < size; i++) {
snprintf(buf, HID_DEBUG_BUFSIZE - 1,
" %02x", data[i]);
hid_debug_event(hid, buf);
}
hid_debug_event(hid, "\n");
kfree(buf);
}
EXPORT_SYMBOL_GPL(hid_dump_report);
void hid_dump_input(struct hid_device *hdev, struct hid_usage *usage, __s32 value)
{
char *buf;
int len;
buf = hid_resolv_usage(usage->hid, NULL);
if (!buf)
return;
len = strlen(buf);
snprintf(buf + len, HID_DEBUG_BUFSIZE - len - 1, " = %d\n", value);
hid_debug_event(hdev, buf);
kfree(buf);
wake_up_interruptible(&hdev->debug_wait);
}
EXPORT_SYMBOL_GPL(hid_dump_input);
static const char *events[EV_MAX + 1] = {
[EV_SYN] = "Sync", [EV_KEY] = "Key",
[EV_REL] = "Relative", [EV_ABS] = "Absolute",
[EV_MSC] = "Misc", [EV_LED] = "LED",
[EV_SND] = "Sound", [EV_REP] = "Repeat",
[EV_FF] = "ForceFeedback", [EV_PWR] = "Power",
[EV_FF_STATUS] = "ForceFeedbackStatus",
};
static const char *syncs[3] = {
[SYN_REPORT] = "Report", [SYN_CONFIG] = "Config",
[SYN_MT_REPORT] = "MT Report",
};
static const char *keys[KEY_MAX + 1] = {
[KEY_RESERVED] = "Reserved", [KEY_ESC] = "Esc",
[KEY_1] = "1", [KEY_2] = "2",
[KEY_3] = "3", [KEY_4] = "4",
[KEY_5] = "5", [KEY_6] = "6",
[KEY_7] = "7", [KEY_8] = "8",
[KEY_9] = "9", [KEY_0] = "0",
[KEY_MINUS] = "Minus", [KEY_EQUAL] = "Equal",
[KEY_BACKSPACE] = "Backspace", [KEY_TAB] = "Tab",
[KEY_Q] = "Q", [KEY_W] = "W",
[KEY_E] = "E", [KEY_R] = "R",
[KEY_T] = "T", [KEY_Y] = "Y",
[KEY_U] = "U", [KEY_I] = "I",
[KEY_O] = "O", [KEY_P] = "P",
[KEY_LEFTBRACE] = "LeftBrace", [KEY_RIGHTBRACE] = "RightBrace",
[KEY_ENTER] = "Enter", [KEY_LEFTCTRL] = "LeftControl",
[KEY_A] = "A", [KEY_S] = "S",
[KEY_D] = "D", [KEY_F] = "F",
[KEY_G] = "G", [KEY_H] = "H",
[KEY_J] = "J", [KEY_K] = "K",
[KEY_L] = "L", [KEY_SEMICOLON] = "Semicolon",
[KEY_APOSTROPHE] = "Apostrophe", [KEY_GRAVE] = "Grave",
[KEY_LEFTSHIFT] = "LeftShift", [KEY_BACKSLASH] = "BackSlash",
[KEY_Z] = "Z", [KEY_X] = "X",
[KEY_C] = "C", [KEY_V] = "V",
[KEY_B] = "B", [KEY_N] = "N",
[KEY_M] = "M", [KEY_COMMA] = "Comma",
[KEY_DOT] = "Dot", [KEY_SLASH] = "Slash",
[KEY_RIGHTSHIFT] = "RightShift", [KEY_KPASTERISK] = "KPAsterisk",
[KEY_LEFTALT] = "LeftAlt", [KEY_SPACE] = "Space",
[KEY_CAPSLOCK] = "CapsLock", [KEY_F1] = "F1",
[KEY_F2] = "F2", [KEY_F3] = "F3",
[KEY_F4] = "F4", [KEY_F5] = "F5",
[KEY_F6] = "F6", [KEY_F7] = "F7",
[KEY_F8] = "F8", [KEY_F9] = "F9",
[KEY_F10] = "F10", [KEY_NUMLOCK] = "NumLock",
[KEY_SCROLLLOCK] = "ScrollLock", [KEY_KP7] = "KP7",
[KEY_KP8] = "KP8", [KEY_KP9] = "KP9",
[KEY_KPMINUS] = "KPMinus", [KEY_KP4] = "KP4",
[KEY_KP5] = "KP5", [KEY_KP6] = "KP6",
[KEY_KPPLUS] = "KPPlus", [KEY_KP1] = "KP1",
[KEY_KP2] = "KP2", [KEY_KP3] = "KP3",
[KEY_KP0] = "KP0", [KEY_KPDOT] = "KPDot",
[KEY_ZENKAKUHANKAKU] = "Zenkaku/Hankaku", [KEY_102ND] = "102nd",
[KEY_F11] = "F11", [KEY_F12] = "F12",
[KEY_RO] = "RO", [KEY_KATAKANA] = "Katakana",
[KEY_HIRAGANA] = "HIRAGANA", [KEY_HENKAN] = "Henkan",
[KEY_KATAKANAHIRAGANA] = "Katakana/Hiragana", [KEY_MUHENKAN] = "Muhenkan",
[KEY_KPJPCOMMA] = "KPJpComma", [KEY_KPENTER] = "KPEnter",
[KEY_RIGHTCTRL] = "RightCtrl", [KEY_KPSLASH] = "KPSlash",
[KEY_SYSRQ] = "SysRq", [KEY_RIGHTALT] = "RightAlt",
[KEY_LINEFEED] = "LineFeed", [KEY_HOME] = "Home",
[KEY_UP] = "Up", [KEY_PAGEUP] = "PageUp",
[KEY_LEFT] = "Left", [KEY_RIGHT] = "Right",
[KEY_END] = "End", [KEY_DOWN] = "Down",
[KEY_PAGEDOWN] = "PageDown", [KEY_INSERT] = "Insert",
[KEY_DELETE] = "Delete", [KEY_MACRO] = "Macro",
[KEY_MUTE] = "Mute", [KEY_VOLUMEDOWN] = "VolumeDown",
[KEY_VOLUMEUP] = "VolumeUp", [KEY_POWER] = "Power",
[KEY_KPEQUAL] = "KPEqual", [KEY_KPPLUSMINUS] = "KPPlusMinus",
[KEY_PAUSE] = "Pause", [KEY_KPCOMMA] = "KPComma",
[KEY_HANGUEL] = "Hangeul", [KEY_HANJA] = "Hanja",
[KEY_YEN] = "Yen", [KEY_LEFTMETA] = "LeftMeta",
[KEY_RIGHTMETA] = "RightMeta", [KEY_COMPOSE] = "Compose",
[KEY_STOP] = "Stop", [KEY_AGAIN] = "Again",
[KEY_PROPS] = "Props", [KEY_UNDO] = "Undo",
[KEY_FRONT] = "Front", [KEY_COPY] = "Copy",
[KEY_OPEN] = "Open", [KEY_PASTE] = "Paste",
[KEY_FIND] = "Find", [KEY_CUT] = "Cut",
[KEY_HELP] = "Help", [KEY_MENU] = "Menu",
[KEY_CALC] = "Calc", [KEY_SETUP] = "Setup",
[KEY_SLEEP] = "Sleep", [KEY_WAKEUP] = "WakeUp",
[KEY_FILE] = "File", [KEY_SENDFILE] = "SendFile",
[KEY_DELETEFILE] = "DeleteFile", [KEY_XFER] = "X-fer",
[KEY_PROG1] = "Prog1", [KEY_PROG2] = "Prog2",
[KEY_WWW] = "WWW", [KEY_MSDOS] = "MSDOS",
[KEY_COFFEE] = "Coffee", [KEY_DIRECTION] = "Direction",
[KEY_CYCLEWINDOWS] = "CycleWindows", [KEY_MAIL] = "Mail",
[KEY_BOOKMARKS] = "Bookmarks", [KEY_COMPUTER] = "Computer",
[KEY_BACK] = "Back", [KEY_FORWARD] = "Forward",
[KEY_CLOSECD] = "CloseCD", [KEY_EJECTCD] = "EjectCD",
[KEY_EJECTCLOSECD] = "EjectCloseCD", [KEY_NEXTSONG] = "NextSong",
[KEY_PLAYPAUSE] = "PlayPause", [KEY_PREVIOUSSONG] = "PreviousSong",
[KEY_STOPCD] = "StopCD", [KEY_RECORD] = "Record",
[KEY_REWIND] = "Rewind", [KEY_PHONE] = "Phone",
[KEY_ISO] = "ISOKey", [KEY_CONFIG] = "Config",
[KEY_HOMEPAGE] = "HomePage", [KEY_REFRESH] = "Refresh",
[KEY_EXIT] = "Exit", [KEY_MOVE] = "Move",
[KEY_EDIT] = "Edit", [KEY_SCROLLUP] = "ScrollUp",
[KEY_SCROLLDOWN] = "ScrollDown", [KEY_KPLEFTPAREN] = "KPLeftParenthesis",
[KEY_KPRIGHTPAREN] = "KPRightParenthesis", [KEY_NEW] = "New",
[KEY_REDO] = "Redo", [KEY_F13] = "F13",
[KEY_F14] = "F14", [KEY_F15] = "F15",
[KEY_F16] = "F16", [KEY_F17] = "F17",
[KEY_F18] = "F18", [KEY_F19] = "F19",
[KEY_F20] = "F20", [KEY_F21] = "F21",
[KEY_F22] = "F22", [KEY_F23] = "F23",
[KEY_F24] = "F24", [KEY_PLAYCD] = "PlayCD",
[KEY_PAUSECD] = "PauseCD", [KEY_PROG3] = "Prog3",
[KEY_PROG4] = "Prog4", [KEY_SUSPEND] = "Suspend",
[KEY_CLOSE] = "Close", [KEY_PLAY] = "Play",
[KEY_FASTFORWARD] = "FastForward", [KEY_BASSBOOST] = "BassBoost",
[KEY_PRINT] = "Print", [KEY_HP] = "HP",
[KEY_CAMERA] = "Camera", [KEY_SOUND] = "Sound",
[KEY_QUESTION] = "Question", [KEY_EMAIL] = "Email",
[KEY_CHAT] = "Chat", [KEY_SEARCH] = "Search",
[KEY_CONNECT] = "Connect", [KEY_FINANCE] = "Finance",
[KEY_SPORT] = "Sport", [KEY_SHOP] = "Shop",
[KEY_ALTERASE] = "AlternateErase", [KEY_CANCEL] = "Cancel",
[KEY_BRIGHTNESSDOWN] = "BrightnessDown", [KEY_BRIGHTNESSUP] = "BrightnessUp",
[KEY_MEDIA] = "Media", [KEY_UNKNOWN] = "Unknown",
[BTN_0] = "Btn0", [BTN_1] = "Btn1",
[BTN_2] = "Btn2", [BTN_3] = "Btn3",
[BTN_4] = "Btn4", [BTN_5] = "Btn5",
[BTN_6] = "Btn6", [BTN_7] = "Btn7",
[BTN_8] = "Btn8", [BTN_9] = "Btn9",
[BTN_LEFT] = "LeftBtn", [BTN_RIGHT] = "RightBtn",
[BTN_MIDDLE] = "MiddleBtn", [BTN_SIDE] = "SideBtn",
[BTN_EXTRA] = "ExtraBtn", [BTN_FORWARD] = "ForwardBtn",
[BTN_BACK] = "BackBtn", [BTN_TASK] = "TaskBtn",
[BTN_TRIGGER] = "Trigger", [BTN_THUMB] = "ThumbBtn",
[BTN_THUMB2] = "ThumbBtn2", [BTN_TOP] = "TopBtn",
[BTN_TOP2] = "TopBtn2", [BTN_PINKIE] = "PinkieBtn",
[BTN_BASE] = "BaseBtn", [BTN_BASE2] = "BaseBtn2",
[BTN_BASE3] = "BaseBtn3", [BTN_BASE4] = "BaseBtn4",
[BTN_BASE5] = "BaseBtn5", [BTN_BASE6] = "BaseBtn6",
[BTN_DEAD] = "BtnDead", [BTN_A] = "BtnA",
[BTN_B] = "BtnB", [BTN_C] = "BtnC",
[BTN_X] = "BtnX", [BTN_Y] = "BtnY",
[BTN_Z] = "BtnZ", [BTN_TL] = "BtnTL",
[BTN_TR] = "BtnTR", [BTN_TL2] = "BtnTL2",
[BTN_TR2] = "BtnTR2", [BTN_SELECT] = "BtnSelect",
[BTN_START] = "BtnStart", [BTN_MODE] = "BtnMode",
[BTN_THUMBL] = "BtnThumbL", [BTN_THUMBR] = "BtnThumbR",
[BTN_TOOL_PEN] = "ToolPen", [BTN_TOOL_RUBBER] = "ToolRubber",
[BTN_TOOL_BRUSH] = "ToolBrush", [BTN_TOOL_PENCIL] = "ToolPencil",
[BTN_TOOL_AIRBRUSH] = "ToolAirbrush", [BTN_TOOL_FINGER] = "ToolFinger",
[BTN_TOOL_MOUSE] = "ToolMouse", [BTN_TOOL_LENS] = "ToolLens",
[BTN_TOUCH] = "Touch", [BTN_STYLUS] = "Stylus",
[BTN_STYLUS2] = "Stylus2", [BTN_TOOL_DOUBLETAP] = "ToolDoubleTap",
[BTN_TOOL_TRIPLETAP] = "ToolTripleTap", [BTN_GEAR_DOWN] = "WheelBtn",
[BTN_GEAR_UP] = "Gear up", [KEY_OK] = "Ok",
[KEY_SELECT] = "Select", [KEY_GOTO] = "Goto",
[KEY_CLEAR] = "Clear", [KEY_POWER2] = "Power2",
[KEY_OPTION] = "Option", [KEY_INFO] = "Info",
[KEY_TIME] = "Time", [KEY_VENDOR] = "Vendor",
[KEY_ARCHIVE] = "Archive", [KEY_PROGRAM] = "Program",
[KEY_CHANNEL] = "Channel", [KEY_FAVORITES] = "Favorites",
[KEY_EPG] = "EPG", [KEY_PVR] = "PVR",
[KEY_MHP] = "MHP", [KEY_LANGUAGE] = "Language",
[KEY_TITLE] = "Title", [KEY_SUBTITLE] = "Subtitle",
[KEY_ANGLE] = "Angle", [KEY_ZOOM] = "Zoom",
[KEY_MODE] = "Mode", [KEY_KEYBOARD] = "Keyboard",
[KEY_SCREEN] = "Screen", [KEY_PC] = "PC",
[KEY_TV] = "TV", [KEY_TV2] = "TV2",
[KEY_VCR] = "VCR", [KEY_VCR2] = "VCR2",
[KEY_SAT] = "Sat", [KEY_SAT2] = "Sat2",
[KEY_CD] = "CD", [KEY_TAPE] = "Tape",
[KEY_RADIO] = "Radio", [KEY_TUNER] = "Tuner",
[KEY_PLAYER] = "Player", [KEY_TEXT] = "Text",
[KEY_DVD] = "DVD", [KEY_AUX] = "Aux",
[KEY_MP3] = "MP3", [KEY_AUDIO] = "Audio",
[KEY_VIDEO] = "Video", [KEY_DIRECTORY] = "Directory",
[KEY_LIST] = "List", [KEY_MEMO] = "Memo",
[KEY_CALENDAR] = "Calendar", [KEY_RED] = "Red",
[KEY_GREEN] = "Green", [KEY_YELLOW] = "Yellow",
[KEY_BLUE] = "Blue", [KEY_CHANNELUP] = "ChannelUp",
[KEY_CHANNELDOWN] = "ChannelDown", [KEY_FIRST] = "First",
[KEY_LAST] = "Last", [KEY_AB] = "AB",
[KEY_NEXT] = "Next", [KEY_RESTART] = "Restart",
[KEY_SLOW] = "Slow", [KEY_SHUFFLE] = "Shuffle",
[KEY_BREAK] = "Break", [KEY_PREVIOUS] = "Previous",
[KEY_DIGITS] = "Digits", [KEY_TEEN] = "TEEN",
[KEY_TWEN] = "TWEN", [KEY_DEL_EOL] = "DeleteEOL",
[KEY_DEL_EOS] = "DeleteEOS", [KEY_INS_LINE] = "InsertLine",
[KEY_DEL_LINE] = "DeleteLine",
[KEY_SEND] = "Send", [KEY_REPLY] = "Reply",
[KEY_FORWARDMAIL] = "ForwardMail", [KEY_SAVE] = "Save",
[KEY_DOCUMENTS] = "Documents", [KEY_SPELLCHECK] = "SpellCheck",
[KEY_LOGOFF] = "Logoff",
[KEY_FN] = "Fn", [KEY_FN_ESC] = "Fn+ESC",
[KEY_FN_1] = "Fn+1", [KEY_FN_2] = "Fn+2",
[KEY_FN_B] = "Fn+B", [KEY_FN_D] = "Fn+D",
[KEY_FN_E] = "Fn+E", [KEY_FN_F] = "Fn+F",
[KEY_FN_S] = "Fn+S",
[KEY_FN_F1] = "Fn+F1", [KEY_FN_F2] = "Fn+F2",
[KEY_FN_F3] = "Fn+F3", [KEY_FN_F4] = "Fn+F4",
[KEY_FN_F5] = "Fn+F5", [KEY_FN_F6] = "Fn+F6",
[KEY_FN_F7] = "Fn+F7", [KEY_FN_F8] = "Fn+F8",
[KEY_FN_F9] = "Fn+F9", [KEY_FN_F10] = "Fn+F10",
[KEY_FN_F11] = "Fn+F11", [KEY_FN_F12] = "Fn+F12",
[KEY_KBDILLUMTOGGLE] = "KbdIlluminationToggle",
[KEY_KBDILLUMDOWN] = "KbdIlluminationDown",
[KEY_KBDILLUMUP] = "KbdIlluminationUp",
[KEY_SWITCHVIDEOMODE] = "SwitchVideoMode",
};
static const char *relatives[REL_MAX + 1] = {
[REL_X] = "X", [REL_Y] = "Y",
[REL_Z] = "Z", [REL_RX] = "Rx",
[REL_RY] = "Ry", [REL_RZ] = "Rz",
[REL_HWHEEL] = "HWheel", [REL_DIAL] = "Dial",
[REL_WHEEL] = "Wheel", [REL_MISC] = "Misc",
};
static const char *absolutes[ABS_CNT] = {
[ABS_X] = "X", [ABS_Y] = "Y",
[ABS_Z] = "Z", [ABS_RX] = "Rx",
[ABS_RY] = "Ry", [ABS_RZ] = "Rz",
[ABS_THROTTLE] = "Throttle", [ABS_RUDDER] = "Rudder",
[ABS_WHEEL] = "Wheel", [ABS_GAS] = "Gas",
[ABS_BRAKE] = "Brake", [ABS_HAT0X] = "Hat0X",
[ABS_HAT0Y] = "Hat0Y", [ABS_HAT1X] = "Hat1X",
[ABS_HAT1Y] = "Hat1Y", [ABS_HAT2X] = "Hat2X",
[ABS_HAT2Y] = "Hat2Y", [ABS_HAT3X] = "Hat3X",
[ABS_HAT3Y] = "Hat 3Y", [ABS_PRESSURE] = "Pressure",
[ABS_DISTANCE] = "Distance", [ABS_TILT_X] = "XTilt",
[ABS_TILT_Y] = "YTilt", [ABS_TOOL_WIDTH] = "ToolWidth",
[ABS_VOLUME] = "Volume", [ABS_MISC] = "Misc",
[ABS_MT_TOUCH_MAJOR] = "MTMajor",
[ABS_MT_TOUCH_MINOR] = "MTMinor",
[ABS_MT_WIDTH_MAJOR] = "MTMajorW",
[ABS_MT_WIDTH_MINOR] = "MTMinorW",
[ABS_MT_ORIENTATION] = "MTOrientation",
[ABS_MT_POSITION_X] = "MTPositionX",
[ABS_MT_POSITION_Y] = "MTPositionY",
[ABS_MT_TOOL_TYPE] = "MTToolType",
[ABS_MT_BLOB_ID] = "MTBlobID",
};
static const char *misc[MSC_MAX + 1] = {
[MSC_SERIAL] = "Serial", [MSC_PULSELED] = "Pulseled",
[MSC_GESTURE] = "Gesture", [MSC_RAW] = "RawData"
};
static const char *leds[LED_MAX + 1] = {
[LED_NUML] = "NumLock", [LED_CAPSL] = "CapsLock",
[LED_SCROLLL] = "ScrollLock", [LED_COMPOSE] = "Compose",
[LED_KANA] = "Kana", [LED_SLEEP] = "Sleep",
[LED_SUSPEND] = "Suspend", [LED_MUTE] = "Mute",
[LED_MISC] = "Misc",
};
static const char *repeats[REP_MAX + 1] = {
[REP_DELAY] = "Delay", [REP_PERIOD] = "Period"
};
static const char *sounds[SND_MAX + 1] = {
[SND_CLICK] = "Click", [SND_BELL] = "Bell",
[SND_TONE] = "Tone"
};
static const char **names[EV_MAX + 1] = {
[EV_SYN] = syncs, [EV_KEY] = keys,
[EV_REL] = relatives, [EV_ABS] = absolutes,
[EV_MSC] = misc, [EV_LED] = leds,
[EV_SND] = sounds, [EV_REP] = repeats,
};
static void hid_resolv_event(__u8 type, __u16 code, struct seq_file *f)
{
seq_printf(f, "%s.%s", events[type] ? events[type] : "?",
names[type] ? (names[type][code] ? names[type][code] : "?") : "?");
}
static void hid_dump_input_mapping(struct hid_device *hid, struct seq_file *f)
{
int i, j, k;
struct hid_report *report;
struct hid_usage *usage;
for (k = HID_INPUT_REPORT; k <= HID_OUTPUT_REPORT; k++) {
list_for_each_entry(report, &hid->report_enum[k].report_list, list) {
for (i = 0; i < report->maxfield; i++) {
for ( j = 0; j < report->field[i]->maxusage; j++) {
usage = report->field[i]->usage + j;
hid_resolv_usage(usage->hid, f);
seq_printf(f, " ---> ");
hid_resolv_event(usage->type, usage->code, f);
seq_printf(f, "\n");
}
}
}
}
}
static int hid_debug_rdesc_show(struct seq_file *f, void *p)
{
struct hid_device *hdev = f->private;
const __u8 *rdesc = hdev->rdesc;
unsigned rsize = hdev->rsize;
int i;
if (!rdesc) {
rdesc = hdev->dev_rdesc;
rsize = hdev->dev_rsize;
}
/* dump HID report descriptor */
for (i = 0; i < rsize; i++)
seq_printf(f, "%02x ", rdesc[i]);
seq_printf(f, "\n\n");
/* dump parsed data and input mappings */
hid_dump_device(hdev, f);
seq_printf(f, "\n");
hid_dump_input_mapping(hdev, f);
return 0;
}
static int hid_debug_rdesc_open(struct inode *inode, struct file *file)
{
return single_open(file, hid_debug_rdesc_show, inode->i_private);
}
static int hid_debug_events_open(struct inode *inode, struct file *file)
{
int err = 0;
struct hid_debug_list *list;
HID: debug: fix RCU preemption issue Commit 2353f2bea ("HID: protect hid_debug_list") introduced mutex locking around debug_list access to prevent SMP races when debugfs nodes are being operated upon by multiple userspace processess. mutex is not a proper synchronization primitive though, as the hid-debug callbacks are being called from atomic contexts. We also have to be careful about disabling IRQs when taking the lock to prevent deadlock against IRQ handlers. Benjamin reports this has also been reported in RH bugzilla as bug #958935. =============================== [ INFO: suspicious RCU usage. ] 3.9.0+ #94 Not tainted ------------------------------- include/linux/rcupdate.h:476 Illegal context switch in RCU read-side critical section! other info that might help us debug this: rcu_scheduler_active = 1, debug_locks = 0 4 locks held by Xorg/5502: #0: (&evdev->mutex){+.+...}, at: [<ffffffff81512c3d>] evdev_write+0x6d/0x160 #1: (&(&dev->event_lock)->rlock#2){-.-...}, at: [<ffffffff8150dd9b>] input_inject_event+0x5b/0x230 #2: (rcu_read_lock){.+.+..}, at: [<ffffffff8150dd82>] input_inject_event+0x42/0x230 #3: (&(&usbhid->lock)->rlock){-.....}, at: [<ffffffff81565289>] usb_hidinput_input_event+0x89/0x120 stack backtrace: CPU: 0 PID: 5502 Comm: Xorg Not tainted 3.9.0+ #94 Hardware name: Dell Inc. OptiPlex 390/0M5DCD, BIOS A09 07/24/2012 0000000000000001 ffff8800689c7c38 ffffffff816f249f ffff8800689c7c68 ffffffff810acb1d 0000000000000000 ffffffff81a03ac7 000000000000019d 0000000000000000 ffff8800689c7c90 ffffffff8107cda7 0000000000000000 Call Trace: [<ffffffff816f249f>] dump_stack+0x19/0x1b [<ffffffff810acb1d>] lockdep_rcu_suspicious+0xfd/0x130 [<ffffffff8107cda7>] __might_sleep+0xc7/0x230 [<ffffffff816f7770>] mutex_lock_nested+0x40/0x3a0 [<ffffffff81312ac4>] ? vsnprintf+0x354/0x640 [<ffffffff81553cc4>] hid_debug_event+0x34/0x100 [<ffffffff81554197>] hid_dump_input+0x67/0xa0 [<ffffffff81556430>] hid_set_field+0x50/0x120 [<ffffffff8156529a>] usb_hidinput_input_event+0x9a/0x120 [<ffffffff8150d89e>] input_handle_event+0x8e/0x530 [<ffffffff8150df10>] input_inject_event+0x1d0/0x230 [<ffffffff8150dd82>] ? input_inject_event+0x42/0x230 [<ffffffff81512cae>] evdev_write+0xde/0x160 [<ffffffff81185038>] vfs_write+0xc8/0x1f0 [<ffffffff81185535>] SyS_write+0x55/0xa0 [<ffffffff81704482>] system_call_fastpath+0x16/0x1b BUG: sleeping function called from invalid context at kernel/mutex.c:413 in_atomic(): 1, irqs_disabled(): 1, pid: 5502, name: Xorg INFO: lockdep is turned off. irq event stamp: 1098574 hardirqs last enabled at (1098573): [<ffffffff816fb53f>] _raw_spin_unlock_irqrestore+0x3f/0x70 hardirqs last disabled at (1098574): [<ffffffff816faaf5>] _raw_spin_lock_irqsave+0x25/0xa0 softirqs last enabled at (1098306): [<ffffffff8104971f>] __do_softirq+0x18f/0x3c0 softirqs last disabled at (1097867): [<ffffffff81049ad5>] irq_exit+0xa5/0xb0 CPU: 0 PID: 5502 Comm: Xorg Not tainted 3.9.0+ #94 Hardware name: Dell Inc. OptiPlex 390/0M5DCD, BIOS A09 07/24/2012 ffffffff81a03ac7 ffff8800689c7c68 ffffffff816f249f ffff8800689c7c90 ffffffff8107ce60 0000000000000000 ffff8800689c7fd8 ffff88006a62c800 ffff8800689c7d10 ffffffff816f7770 ffff8800689c7d00 ffffffff81312ac4 Call Trace: [<ffffffff816f249f>] dump_stack+0x19/0x1b [<ffffffff8107ce60>] __might_sleep+0x180/0x230 [<ffffffff816f7770>] mutex_lock_nested+0x40/0x3a0 [<ffffffff81312ac4>] ? vsnprintf+0x354/0x640 [<ffffffff81553cc4>] hid_debug_event+0x34/0x100 [<ffffffff81554197>] hid_dump_input+0x67/0xa0 [<ffffffff81556430>] hid_set_field+0x50/0x120 [<ffffffff8156529a>] usb_hidinput_input_event+0x9a/0x120 [<ffffffff8150d89e>] input_handle_event+0x8e/0x530 [<ffffffff8150df10>] input_inject_event+0x1d0/0x230 [<ffffffff8150dd82>] ? input_inject_event+0x42/0x230 [<ffffffff81512cae>] evdev_write+0xde/0x160 [<ffffffff81185038>] vfs_write+0xc8/0x1f0 [<ffffffff81185535>] SyS_write+0x55/0xa0 [<ffffffff81704482>] system_call_fastpath+0x16/0x1b Reported-by: majianpeng <majianpeng@gmail.com> Reported-by: Benjamin Tissoires <benjamin.tissoires@gmail.com> Reviewed-by: Dmitry Torokhov <dmitry.torokhov@gmail.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2013-05-06 19:05:50 +08:00
unsigned long flags;
if (!(list = kzalloc(sizeof(struct hid_debug_list), GFP_KERNEL))) {
err = -ENOMEM;
goto out;
}
if (!(list->hid_debug_buf = kzalloc(sizeof(char) * HID_DEBUG_BUFSIZE, GFP_KERNEL))) {
err = -ENOMEM;
kfree(list);
goto out;
}
list->hdev = (struct hid_device *) inode->i_private;
file->private_data = list;
mutex_init(&list->read_mutex);
HID: debug: fix RCU preemption issue Commit 2353f2bea ("HID: protect hid_debug_list") introduced mutex locking around debug_list access to prevent SMP races when debugfs nodes are being operated upon by multiple userspace processess. mutex is not a proper synchronization primitive though, as the hid-debug callbacks are being called from atomic contexts. We also have to be careful about disabling IRQs when taking the lock to prevent deadlock against IRQ handlers. Benjamin reports this has also been reported in RH bugzilla as bug #958935. =============================== [ INFO: suspicious RCU usage. ] 3.9.0+ #94 Not tainted ------------------------------- include/linux/rcupdate.h:476 Illegal context switch in RCU read-side critical section! other info that might help us debug this: rcu_scheduler_active = 1, debug_locks = 0 4 locks held by Xorg/5502: #0: (&evdev->mutex){+.+...}, at: [<ffffffff81512c3d>] evdev_write+0x6d/0x160 #1: (&(&dev->event_lock)->rlock#2){-.-...}, at: [<ffffffff8150dd9b>] input_inject_event+0x5b/0x230 #2: (rcu_read_lock){.+.+..}, at: [<ffffffff8150dd82>] input_inject_event+0x42/0x230 #3: (&(&usbhid->lock)->rlock){-.....}, at: [<ffffffff81565289>] usb_hidinput_input_event+0x89/0x120 stack backtrace: CPU: 0 PID: 5502 Comm: Xorg Not tainted 3.9.0+ #94 Hardware name: Dell Inc. OptiPlex 390/0M5DCD, BIOS A09 07/24/2012 0000000000000001 ffff8800689c7c38 ffffffff816f249f ffff8800689c7c68 ffffffff810acb1d 0000000000000000 ffffffff81a03ac7 000000000000019d 0000000000000000 ffff8800689c7c90 ffffffff8107cda7 0000000000000000 Call Trace: [<ffffffff816f249f>] dump_stack+0x19/0x1b [<ffffffff810acb1d>] lockdep_rcu_suspicious+0xfd/0x130 [<ffffffff8107cda7>] __might_sleep+0xc7/0x230 [<ffffffff816f7770>] mutex_lock_nested+0x40/0x3a0 [<ffffffff81312ac4>] ? vsnprintf+0x354/0x640 [<ffffffff81553cc4>] hid_debug_event+0x34/0x100 [<ffffffff81554197>] hid_dump_input+0x67/0xa0 [<ffffffff81556430>] hid_set_field+0x50/0x120 [<ffffffff8156529a>] usb_hidinput_input_event+0x9a/0x120 [<ffffffff8150d89e>] input_handle_event+0x8e/0x530 [<ffffffff8150df10>] input_inject_event+0x1d0/0x230 [<ffffffff8150dd82>] ? input_inject_event+0x42/0x230 [<ffffffff81512cae>] evdev_write+0xde/0x160 [<ffffffff81185038>] vfs_write+0xc8/0x1f0 [<ffffffff81185535>] SyS_write+0x55/0xa0 [<ffffffff81704482>] system_call_fastpath+0x16/0x1b BUG: sleeping function called from invalid context at kernel/mutex.c:413 in_atomic(): 1, irqs_disabled(): 1, pid: 5502, name: Xorg INFO: lockdep is turned off. irq event stamp: 1098574 hardirqs last enabled at (1098573): [<ffffffff816fb53f>] _raw_spin_unlock_irqrestore+0x3f/0x70 hardirqs last disabled at (1098574): [<ffffffff816faaf5>] _raw_spin_lock_irqsave+0x25/0xa0 softirqs last enabled at (1098306): [<ffffffff8104971f>] __do_softirq+0x18f/0x3c0 softirqs last disabled at (1097867): [<ffffffff81049ad5>] irq_exit+0xa5/0xb0 CPU: 0 PID: 5502 Comm: Xorg Not tainted 3.9.0+ #94 Hardware name: Dell Inc. OptiPlex 390/0M5DCD, BIOS A09 07/24/2012 ffffffff81a03ac7 ffff8800689c7c68 ffffffff816f249f ffff8800689c7c90 ffffffff8107ce60 0000000000000000 ffff8800689c7fd8 ffff88006a62c800 ffff8800689c7d10 ffffffff816f7770 ffff8800689c7d00 ffffffff81312ac4 Call Trace: [<ffffffff816f249f>] dump_stack+0x19/0x1b [<ffffffff8107ce60>] __might_sleep+0x180/0x230 [<ffffffff816f7770>] mutex_lock_nested+0x40/0x3a0 [<ffffffff81312ac4>] ? vsnprintf+0x354/0x640 [<ffffffff81553cc4>] hid_debug_event+0x34/0x100 [<ffffffff81554197>] hid_dump_input+0x67/0xa0 [<ffffffff81556430>] hid_set_field+0x50/0x120 [<ffffffff8156529a>] usb_hidinput_input_event+0x9a/0x120 [<ffffffff8150d89e>] input_handle_event+0x8e/0x530 [<ffffffff8150df10>] input_inject_event+0x1d0/0x230 [<ffffffff8150dd82>] ? input_inject_event+0x42/0x230 [<ffffffff81512cae>] evdev_write+0xde/0x160 [<ffffffff81185038>] vfs_write+0xc8/0x1f0 [<ffffffff81185535>] SyS_write+0x55/0xa0 [<ffffffff81704482>] system_call_fastpath+0x16/0x1b Reported-by: majianpeng <majianpeng@gmail.com> Reported-by: Benjamin Tissoires <benjamin.tissoires@gmail.com> Reviewed-by: Dmitry Torokhov <dmitry.torokhov@gmail.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2013-05-06 19:05:50 +08:00
spin_lock_irqsave(&list->hdev->debug_list_lock, flags);
list_add_tail(&list->node, &list->hdev->debug_list);
HID: debug: fix RCU preemption issue Commit 2353f2bea ("HID: protect hid_debug_list") introduced mutex locking around debug_list access to prevent SMP races when debugfs nodes are being operated upon by multiple userspace processess. mutex is not a proper synchronization primitive though, as the hid-debug callbacks are being called from atomic contexts. We also have to be careful about disabling IRQs when taking the lock to prevent deadlock against IRQ handlers. Benjamin reports this has also been reported in RH bugzilla as bug #958935. =============================== [ INFO: suspicious RCU usage. ] 3.9.0+ #94 Not tainted ------------------------------- include/linux/rcupdate.h:476 Illegal context switch in RCU read-side critical section! other info that might help us debug this: rcu_scheduler_active = 1, debug_locks = 0 4 locks held by Xorg/5502: #0: (&evdev->mutex){+.+...}, at: [<ffffffff81512c3d>] evdev_write+0x6d/0x160 #1: (&(&dev->event_lock)->rlock#2){-.-...}, at: [<ffffffff8150dd9b>] input_inject_event+0x5b/0x230 #2: (rcu_read_lock){.+.+..}, at: [<ffffffff8150dd82>] input_inject_event+0x42/0x230 #3: (&(&usbhid->lock)->rlock){-.....}, at: [<ffffffff81565289>] usb_hidinput_input_event+0x89/0x120 stack backtrace: CPU: 0 PID: 5502 Comm: Xorg Not tainted 3.9.0+ #94 Hardware name: Dell Inc. OptiPlex 390/0M5DCD, BIOS A09 07/24/2012 0000000000000001 ffff8800689c7c38 ffffffff816f249f ffff8800689c7c68 ffffffff810acb1d 0000000000000000 ffffffff81a03ac7 000000000000019d 0000000000000000 ffff8800689c7c90 ffffffff8107cda7 0000000000000000 Call Trace: [<ffffffff816f249f>] dump_stack+0x19/0x1b [<ffffffff810acb1d>] lockdep_rcu_suspicious+0xfd/0x130 [<ffffffff8107cda7>] __might_sleep+0xc7/0x230 [<ffffffff816f7770>] mutex_lock_nested+0x40/0x3a0 [<ffffffff81312ac4>] ? vsnprintf+0x354/0x640 [<ffffffff81553cc4>] hid_debug_event+0x34/0x100 [<ffffffff81554197>] hid_dump_input+0x67/0xa0 [<ffffffff81556430>] hid_set_field+0x50/0x120 [<ffffffff8156529a>] usb_hidinput_input_event+0x9a/0x120 [<ffffffff8150d89e>] input_handle_event+0x8e/0x530 [<ffffffff8150df10>] input_inject_event+0x1d0/0x230 [<ffffffff8150dd82>] ? input_inject_event+0x42/0x230 [<ffffffff81512cae>] evdev_write+0xde/0x160 [<ffffffff81185038>] vfs_write+0xc8/0x1f0 [<ffffffff81185535>] SyS_write+0x55/0xa0 [<ffffffff81704482>] system_call_fastpath+0x16/0x1b BUG: sleeping function called from invalid context at kernel/mutex.c:413 in_atomic(): 1, irqs_disabled(): 1, pid: 5502, name: Xorg INFO: lockdep is turned off. irq event stamp: 1098574 hardirqs last enabled at (1098573): [<ffffffff816fb53f>] _raw_spin_unlock_irqrestore+0x3f/0x70 hardirqs last disabled at (1098574): [<ffffffff816faaf5>] _raw_spin_lock_irqsave+0x25/0xa0 softirqs last enabled at (1098306): [<ffffffff8104971f>] __do_softirq+0x18f/0x3c0 softirqs last disabled at (1097867): [<ffffffff81049ad5>] irq_exit+0xa5/0xb0 CPU: 0 PID: 5502 Comm: Xorg Not tainted 3.9.0+ #94 Hardware name: Dell Inc. OptiPlex 390/0M5DCD, BIOS A09 07/24/2012 ffffffff81a03ac7 ffff8800689c7c68 ffffffff816f249f ffff8800689c7c90 ffffffff8107ce60 0000000000000000 ffff8800689c7fd8 ffff88006a62c800 ffff8800689c7d10 ffffffff816f7770 ffff8800689c7d00 ffffffff81312ac4 Call Trace: [<ffffffff816f249f>] dump_stack+0x19/0x1b [<ffffffff8107ce60>] __might_sleep+0x180/0x230 [<ffffffff816f7770>] mutex_lock_nested+0x40/0x3a0 [<ffffffff81312ac4>] ? vsnprintf+0x354/0x640 [<ffffffff81553cc4>] hid_debug_event+0x34/0x100 [<ffffffff81554197>] hid_dump_input+0x67/0xa0 [<ffffffff81556430>] hid_set_field+0x50/0x120 [<ffffffff8156529a>] usb_hidinput_input_event+0x9a/0x120 [<ffffffff8150d89e>] input_handle_event+0x8e/0x530 [<ffffffff8150df10>] input_inject_event+0x1d0/0x230 [<ffffffff8150dd82>] ? input_inject_event+0x42/0x230 [<ffffffff81512cae>] evdev_write+0xde/0x160 [<ffffffff81185038>] vfs_write+0xc8/0x1f0 [<ffffffff81185535>] SyS_write+0x55/0xa0 [<ffffffff81704482>] system_call_fastpath+0x16/0x1b Reported-by: majianpeng <majianpeng@gmail.com> Reported-by: Benjamin Tissoires <benjamin.tissoires@gmail.com> Reviewed-by: Dmitry Torokhov <dmitry.torokhov@gmail.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2013-05-06 19:05:50 +08:00
spin_unlock_irqrestore(&list->hdev->debug_list_lock, flags);
out:
return err;
}
static ssize_t hid_debug_events_read(struct file *file, char __user *buffer,
size_t count, loff_t *ppos)
{
struct hid_debug_list *list = file->private_data;
int ret = 0, len;
DECLARE_WAITQUEUE(wait, current);
mutex_lock(&list->read_mutex);
while (ret == 0) {
if (list->head == list->tail) {
add_wait_queue(&list->hdev->debug_wait, &wait);
set_current_state(TASK_INTERRUPTIBLE);
while (list->head == list->tail) {
if (file->f_flags & O_NONBLOCK) {
ret = -EAGAIN;
break;
}
if (signal_pending(current)) {
ret = -ERESTARTSYS;
break;
}
if (!list->hdev || !list->hdev->debug) {
ret = -EIO;
break;
}
/* allow O_NONBLOCK from other threads */
mutex_unlock(&list->read_mutex);
schedule();
mutex_lock(&list->read_mutex);
set_current_state(TASK_INTERRUPTIBLE);
}
set_current_state(TASK_RUNNING);
remove_wait_queue(&list->hdev->debug_wait, &wait);
}
if (ret)
goto out;
/* pass the ringbuffer contents to userspace */
copy_rest:
if (list->tail == list->head)
goto out;
if (list->tail > list->head) {
len = list->tail - list->head;
if (copy_to_user(buffer + ret, &list->hid_debug_buf[list->head], len)) {
ret = -EFAULT;
goto out;
}
ret += len;
list->head += len;
} else {
len = HID_DEBUG_BUFSIZE - list->head;
if (copy_to_user(buffer, &list->hid_debug_buf[list->head], len)) {
ret = -EFAULT;
goto out;
}
list->head = 0;
ret += len;
goto copy_rest;
}
}
out:
mutex_unlock(&list->read_mutex);
return ret;
}
static unsigned int hid_debug_events_poll(struct file *file, poll_table *wait)
{
struct hid_debug_list *list = file->private_data;
poll_wait(file, &list->hdev->debug_wait, wait);
if (list->head != list->tail)
return POLLIN | POLLRDNORM;
if (!list->hdev->debug)
return POLLERR | POLLHUP;
return 0;
}
static int hid_debug_events_release(struct inode *inode, struct file *file)
{
struct hid_debug_list *list = file->private_data;
HID: debug: fix RCU preemption issue Commit 2353f2bea ("HID: protect hid_debug_list") introduced mutex locking around debug_list access to prevent SMP races when debugfs nodes are being operated upon by multiple userspace processess. mutex is not a proper synchronization primitive though, as the hid-debug callbacks are being called from atomic contexts. We also have to be careful about disabling IRQs when taking the lock to prevent deadlock against IRQ handlers. Benjamin reports this has also been reported in RH bugzilla as bug #958935. =============================== [ INFO: suspicious RCU usage. ] 3.9.0+ #94 Not tainted ------------------------------- include/linux/rcupdate.h:476 Illegal context switch in RCU read-side critical section! other info that might help us debug this: rcu_scheduler_active = 1, debug_locks = 0 4 locks held by Xorg/5502: #0: (&evdev->mutex){+.+...}, at: [<ffffffff81512c3d>] evdev_write+0x6d/0x160 #1: (&(&dev->event_lock)->rlock#2){-.-...}, at: [<ffffffff8150dd9b>] input_inject_event+0x5b/0x230 #2: (rcu_read_lock){.+.+..}, at: [<ffffffff8150dd82>] input_inject_event+0x42/0x230 #3: (&(&usbhid->lock)->rlock){-.....}, at: [<ffffffff81565289>] usb_hidinput_input_event+0x89/0x120 stack backtrace: CPU: 0 PID: 5502 Comm: Xorg Not tainted 3.9.0+ #94 Hardware name: Dell Inc. OptiPlex 390/0M5DCD, BIOS A09 07/24/2012 0000000000000001 ffff8800689c7c38 ffffffff816f249f ffff8800689c7c68 ffffffff810acb1d 0000000000000000 ffffffff81a03ac7 000000000000019d 0000000000000000 ffff8800689c7c90 ffffffff8107cda7 0000000000000000 Call Trace: [<ffffffff816f249f>] dump_stack+0x19/0x1b [<ffffffff810acb1d>] lockdep_rcu_suspicious+0xfd/0x130 [<ffffffff8107cda7>] __might_sleep+0xc7/0x230 [<ffffffff816f7770>] mutex_lock_nested+0x40/0x3a0 [<ffffffff81312ac4>] ? vsnprintf+0x354/0x640 [<ffffffff81553cc4>] hid_debug_event+0x34/0x100 [<ffffffff81554197>] hid_dump_input+0x67/0xa0 [<ffffffff81556430>] hid_set_field+0x50/0x120 [<ffffffff8156529a>] usb_hidinput_input_event+0x9a/0x120 [<ffffffff8150d89e>] input_handle_event+0x8e/0x530 [<ffffffff8150df10>] input_inject_event+0x1d0/0x230 [<ffffffff8150dd82>] ? input_inject_event+0x42/0x230 [<ffffffff81512cae>] evdev_write+0xde/0x160 [<ffffffff81185038>] vfs_write+0xc8/0x1f0 [<ffffffff81185535>] SyS_write+0x55/0xa0 [<ffffffff81704482>] system_call_fastpath+0x16/0x1b BUG: sleeping function called from invalid context at kernel/mutex.c:413 in_atomic(): 1, irqs_disabled(): 1, pid: 5502, name: Xorg INFO: lockdep is turned off. irq event stamp: 1098574 hardirqs last enabled at (1098573): [<ffffffff816fb53f>] _raw_spin_unlock_irqrestore+0x3f/0x70 hardirqs last disabled at (1098574): [<ffffffff816faaf5>] _raw_spin_lock_irqsave+0x25/0xa0 softirqs last enabled at (1098306): [<ffffffff8104971f>] __do_softirq+0x18f/0x3c0 softirqs last disabled at (1097867): [<ffffffff81049ad5>] irq_exit+0xa5/0xb0 CPU: 0 PID: 5502 Comm: Xorg Not tainted 3.9.0+ #94 Hardware name: Dell Inc. OptiPlex 390/0M5DCD, BIOS A09 07/24/2012 ffffffff81a03ac7 ffff8800689c7c68 ffffffff816f249f ffff8800689c7c90 ffffffff8107ce60 0000000000000000 ffff8800689c7fd8 ffff88006a62c800 ffff8800689c7d10 ffffffff816f7770 ffff8800689c7d00 ffffffff81312ac4 Call Trace: [<ffffffff816f249f>] dump_stack+0x19/0x1b [<ffffffff8107ce60>] __might_sleep+0x180/0x230 [<ffffffff816f7770>] mutex_lock_nested+0x40/0x3a0 [<ffffffff81312ac4>] ? vsnprintf+0x354/0x640 [<ffffffff81553cc4>] hid_debug_event+0x34/0x100 [<ffffffff81554197>] hid_dump_input+0x67/0xa0 [<ffffffff81556430>] hid_set_field+0x50/0x120 [<ffffffff8156529a>] usb_hidinput_input_event+0x9a/0x120 [<ffffffff8150d89e>] input_handle_event+0x8e/0x530 [<ffffffff8150df10>] input_inject_event+0x1d0/0x230 [<ffffffff8150dd82>] ? input_inject_event+0x42/0x230 [<ffffffff81512cae>] evdev_write+0xde/0x160 [<ffffffff81185038>] vfs_write+0xc8/0x1f0 [<ffffffff81185535>] SyS_write+0x55/0xa0 [<ffffffff81704482>] system_call_fastpath+0x16/0x1b Reported-by: majianpeng <majianpeng@gmail.com> Reported-by: Benjamin Tissoires <benjamin.tissoires@gmail.com> Reviewed-by: Dmitry Torokhov <dmitry.torokhov@gmail.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2013-05-06 19:05:50 +08:00
unsigned long flags;
HID: debug: fix RCU preemption issue Commit 2353f2bea ("HID: protect hid_debug_list") introduced mutex locking around debug_list access to prevent SMP races when debugfs nodes are being operated upon by multiple userspace processess. mutex is not a proper synchronization primitive though, as the hid-debug callbacks are being called from atomic contexts. We also have to be careful about disabling IRQs when taking the lock to prevent deadlock against IRQ handlers. Benjamin reports this has also been reported in RH bugzilla as bug #958935. =============================== [ INFO: suspicious RCU usage. ] 3.9.0+ #94 Not tainted ------------------------------- include/linux/rcupdate.h:476 Illegal context switch in RCU read-side critical section! other info that might help us debug this: rcu_scheduler_active = 1, debug_locks = 0 4 locks held by Xorg/5502: #0: (&evdev->mutex){+.+...}, at: [<ffffffff81512c3d>] evdev_write+0x6d/0x160 #1: (&(&dev->event_lock)->rlock#2){-.-...}, at: [<ffffffff8150dd9b>] input_inject_event+0x5b/0x230 #2: (rcu_read_lock){.+.+..}, at: [<ffffffff8150dd82>] input_inject_event+0x42/0x230 #3: (&(&usbhid->lock)->rlock){-.....}, at: [<ffffffff81565289>] usb_hidinput_input_event+0x89/0x120 stack backtrace: CPU: 0 PID: 5502 Comm: Xorg Not tainted 3.9.0+ #94 Hardware name: Dell Inc. OptiPlex 390/0M5DCD, BIOS A09 07/24/2012 0000000000000001 ffff8800689c7c38 ffffffff816f249f ffff8800689c7c68 ffffffff810acb1d 0000000000000000 ffffffff81a03ac7 000000000000019d 0000000000000000 ffff8800689c7c90 ffffffff8107cda7 0000000000000000 Call Trace: [<ffffffff816f249f>] dump_stack+0x19/0x1b [<ffffffff810acb1d>] lockdep_rcu_suspicious+0xfd/0x130 [<ffffffff8107cda7>] __might_sleep+0xc7/0x230 [<ffffffff816f7770>] mutex_lock_nested+0x40/0x3a0 [<ffffffff81312ac4>] ? vsnprintf+0x354/0x640 [<ffffffff81553cc4>] hid_debug_event+0x34/0x100 [<ffffffff81554197>] hid_dump_input+0x67/0xa0 [<ffffffff81556430>] hid_set_field+0x50/0x120 [<ffffffff8156529a>] usb_hidinput_input_event+0x9a/0x120 [<ffffffff8150d89e>] input_handle_event+0x8e/0x530 [<ffffffff8150df10>] input_inject_event+0x1d0/0x230 [<ffffffff8150dd82>] ? input_inject_event+0x42/0x230 [<ffffffff81512cae>] evdev_write+0xde/0x160 [<ffffffff81185038>] vfs_write+0xc8/0x1f0 [<ffffffff81185535>] SyS_write+0x55/0xa0 [<ffffffff81704482>] system_call_fastpath+0x16/0x1b BUG: sleeping function called from invalid context at kernel/mutex.c:413 in_atomic(): 1, irqs_disabled(): 1, pid: 5502, name: Xorg INFO: lockdep is turned off. irq event stamp: 1098574 hardirqs last enabled at (1098573): [<ffffffff816fb53f>] _raw_spin_unlock_irqrestore+0x3f/0x70 hardirqs last disabled at (1098574): [<ffffffff816faaf5>] _raw_spin_lock_irqsave+0x25/0xa0 softirqs last enabled at (1098306): [<ffffffff8104971f>] __do_softirq+0x18f/0x3c0 softirqs last disabled at (1097867): [<ffffffff81049ad5>] irq_exit+0xa5/0xb0 CPU: 0 PID: 5502 Comm: Xorg Not tainted 3.9.0+ #94 Hardware name: Dell Inc. OptiPlex 390/0M5DCD, BIOS A09 07/24/2012 ffffffff81a03ac7 ffff8800689c7c68 ffffffff816f249f ffff8800689c7c90 ffffffff8107ce60 0000000000000000 ffff8800689c7fd8 ffff88006a62c800 ffff8800689c7d10 ffffffff816f7770 ffff8800689c7d00 ffffffff81312ac4 Call Trace: [<ffffffff816f249f>] dump_stack+0x19/0x1b [<ffffffff8107ce60>] __might_sleep+0x180/0x230 [<ffffffff816f7770>] mutex_lock_nested+0x40/0x3a0 [<ffffffff81312ac4>] ? vsnprintf+0x354/0x640 [<ffffffff81553cc4>] hid_debug_event+0x34/0x100 [<ffffffff81554197>] hid_dump_input+0x67/0xa0 [<ffffffff81556430>] hid_set_field+0x50/0x120 [<ffffffff8156529a>] usb_hidinput_input_event+0x9a/0x120 [<ffffffff8150d89e>] input_handle_event+0x8e/0x530 [<ffffffff8150df10>] input_inject_event+0x1d0/0x230 [<ffffffff8150dd82>] ? input_inject_event+0x42/0x230 [<ffffffff81512cae>] evdev_write+0xde/0x160 [<ffffffff81185038>] vfs_write+0xc8/0x1f0 [<ffffffff81185535>] SyS_write+0x55/0xa0 [<ffffffff81704482>] system_call_fastpath+0x16/0x1b Reported-by: majianpeng <majianpeng@gmail.com> Reported-by: Benjamin Tissoires <benjamin.tissoires@gmail.com> Reviewed-by: Dmitry Torokhov <dmitry.torokhov@gmail.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2013-05-06 19:05:50 +08:00
spin_lock_irqsave(&list->hdev->debug_list_lock, flags);
list_del(&list->node);
HID: debug: fix RCU preemption issue Commit 2353f2bea ("HID: protect hid_debug_list") introduced mutex locking around debug_list access to prevent SMP races when debugfs nodes are being operated upon by multiple userspace processess. mutex is not a proper synchronization primitive though, as the hid-debug callbacks are being called from atomic contexts. We also have to be careful about disabling IRQs when taking the lock to prevent deadlock against IRQ handlers. Benjamin reports this has also been reported in RH bugzilla as bug #958935. =============================== [ INFO: suspicious RCU usage. ] 3.9.0+ #94 Not tainted ------------------------------- include/linux/rcupdate.h:476 Illegal context switch in RCU read-side critical section! other info that might help us debug this: rcu_scheduler_active = 1, debug_locks = 0 4 locks held by Xorg/5502: #0: (&evdev->mutex){+.+...}, at: [<ffffffff81512c3d>] evdev_write+0x6d/0x160 #1: (&(&dev->event_lock)->rlock#2){-.-...}, at: [<ffffffff8150dd9b>] input_inject_event+0x5b/0x230 #2: (rcu_read_lock){.+.+..}, at: [<ffffffff8150dd82>] input_inject_event+0x42/0x230 #3: (&(&usbhid->lock)->rlock){-.....}, at: [<ffffffff81565289>] usb_hidinput_input_event+0x89/0x120 stack backtrace: CPU: 0 PID: 5502 Comm: Xorg Not tainted 3.9.0+ #94 Hardware name: Dell Inc. OptiPlex 390/0M5DCD, BIOS A09 07/24/2012 0000000000000001 ffff8800689c7c38 ffffffff816f249f ffff8800689c7c68 ffffffff810acb1d 0000000000000000 ffffffff81a03ac7 000000000000019d 0000000000000000 ffff8800689c7c90 ffffffff8107cda7 0000000000000000 Call Trace: [<ffffffff816f249f>] dump_stack+0x19/0x1b [<ffffffff810acb1d>] lockdep_rcu_suspicious+0xfd/0x130 [<ffffffff8107cda7>] __might_sleep+0xc7/0x230 [<ffffffff816f7770>] mutex_lock_nested+0x40/0x3a0 [<ffffffff81312ac4>] ? vsnprintf+0x354/0x640 [<ffffffff81553cc4>] hid_debug_event+0x34/0x100 [<ffffffff81554197>] hid_dump_input+0x67/0xa0 [<ffffffff81556430>] hid_set_field+0x50/0x120 [<ffffffff8156529a>] usb_hidinput_input_event+0x9a/0x120 [<ffffffff8150d89e>] input_handle_event+0x8e/0x530 [<ffffffff8150df10>] input_inject_event+0x1d0/0x230 [<ffffffff8150dd82>] ? input_inject_event+0x42/0x230 [<ffffffff81512cae>] evdev_write+0xde/0x160 [<ffffffff81185038>] vfs_write+0xc8/0x1f0 [<ffffffff81185535>] SyS_write+0x55/0xa0 [<ffffffff81704482>] system_call_fastpath+0x16/0x1b BUG: sleeping function called from invalid context at kernel/mutex.c:413 in_atomic(): 1, irqs_disabled(): 1, pid: 5502, name: Xorg INFO: lockdep is turned off. irq event stamp: 1098574 hardirqs last enabled at (1098573): [<ffffffff816fb53f>] _raw_spin_unlock_irqrestore+0x3f/0x70 hardirqs last disabled at (1098574): [<ffffffff816faaf5>] _raw_spin_lock_irqsave+0x25/0xa0 softirqs last enabled at (1098306): [<ffffffff8104971f>] __do_softirq+0x18f/0x3c0 softirqs last disabled at (1097867): [<ffffffff81049ad5>] irq_exit+0xa5/0xb0 CPU: 0 PID: 5502 Comm: Xorg Not tainted 3.9.0+ #94 Hardware name: Dell Inc. OptiPlex 390/0M5DCD, BIOS A09 07/24/2012 ffffffff81a03ac7 ffff8800689c7c68 ffffffff816f249f ffff8800689c7c90 ffffffff8107ce60 0000000000000000 ffff8800689c7fd8 ffff88006a62c800 ffff8800689c7d10 ffffffff816f7770 ffff8800689c7d00 ffffffff81312ac4 Call Trace: [<ffffffff816f249f>] dump_stack+0x19/0x1b [<ffffffff8107ce60>] __might_sleep+0x180/0x230 [<ffffffff816f7770>] mutex_lock_nested+0x40/0x3a0 [<ffffffff81312ac4>] ? vsnprintf+0x354/0x640 [<ffffffff81553cc4>] hid_debug_event+0x34/0x100 [<ffffffff81554197>] hid_dump_input+0x67/0xa0 [<ffffffff81556430>] hid_set_field+0x50/0x120 [<ffffffff8156529a>] usb_hidinput_input_event+0x9a/0x120 [<ffffffff8150d89e>] input_handle_event+0x8e/0x530 [<ffffffff8150df10>] input_inject_event+0x1d0/0x230 [<ffffffff8150dd82>] ? input_inject_event+0x42/0x230 [<ffffffff81512cae>] evdev_write+0xde/0x160 [<ffffffff81185038>] vfs_write+0xc8/0x1f0 [<ffffffff81185535>] SyS_write+0x55/0xa0 [<ffffffff81704482>] system_call_fastpath+0x16/0x1b Reported-by: majianpeng <majianpeng@gmail.com> Reported-by: Benjamin Tissoires <benjamin.tissoires@gmail.com> Reviewed-by: Dmitry Torokhov <dmitry.torokhov@gmail.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2013-05-06 19:05:50 +08:00
spin_unlock_irqrestore(&list->hdev->debug_list_lock, flags);
kfree(list->hid_debug_buf);
kfree(list);
return 0;
}
static const struct file_operations hid_debug_rdesc_fops = {
.open = hid_debug_rdesc_open,
.read = seq_read,
.llseek = seq_lseek,
.release = single_release,
};
static const struct file_operations hid_debug_events_fops = {
.owner = THIS_MODULE,
.open = hid_debug_events_open,
.read = hid_debug_events_read,
.poll = hid_debug_events_poll,
.release = hid_debug_events_release,
llseek: automatically add .llseek fop All file_operations should get a .llseek operation so we can make nonseekable_open the default for future file operations without a .llseek pointer. The three cases that we can automatically detect are no_llseek, seq_lseek and default_llseek. For cases where we can we can automatically prove that the file offset is always ignored, we use noop_llseek, which maintains the current behavior of not returning an error from a seek. New drivers should normally not use noop_llseek but instead use no_llseek and call nonseekable_open at open time. Existing drivers can be converted to do the same when the maintainer knows for certain that no user code relies on calling seek on the device file. The generated code is often incorrectly indented and right now contains comments that clarify for each added line why a specific variant was chosen. In the version that gets submitted upstream, the comments will be gone and I will manually fix the indentation, because there does not seem to be a way to do that using coccinelle. Some amount of new code is currently sitting in linux-next that should get the same modifications, which I will do at the end of the merge window. Many thanks to Julia Lawall for helping me learn to write a semantic patch that does all this. ===== begin semantic patch ===== // This adds an llseek= method to all file operations, // as a preparation for making no_llseek the default. // // The rules are // - use no_llseek explicitly if we do nonseekable_open // - use seq_lseek for sequential files // - use default_llseek if we know we access f_pos // - use noop_llseek if we know we don't access f_pos, // but we still want to allow users to call lseek // @ open1 exists @ identifier nested_open; @@ nested_open(...) { <+... nonseekable_open(...) ...+> } @ open exists@ identifier open_f; identifier i, f; identifier open1.nested_open; @@ int open_f(struct inode *i, struct file *f) { <+... ( nonseekable_open(...) | nested_open(...) ) ...+> } @ read disable optional_qualifier exists @ identifier read_f; identifier f, p, s, off; type ssize_t, size_t, loff_t; expression E; identifier func; @@ ssize_t read_f(struct file *f, char *p, size_t s, loff_t *off) { <+... ( *off = E | *off += E | func(..., off, ...) | E = *off ) ...+> } @ read_no_fpos disable optional_qualifier exists @ identifier read_f; identifier f, p, s, off; type ssize_t, size_t, loff_t; @@ ssize_t read_f(struct file *f, char *p, size_t s, loff_t *off) { ... when != off } @ write @ identifier write_f; identifier f, p, s, off; type ssize_t, size_t, loff_t; expression E; identifier func; @@ ssize_t write_f(struct file *f, const char *p, size_t s, loff_t *off) { <+... ( *off = E | *off += E | func(..., off, ...) | E = *off ) ...+> } @ write_no_fpos @ identifier write_f; identifier f, p, s, off; type ssize_t, size_t, loff_t; @@ ssize_t write_f(struct file *f, const char *p, size_t s, loff_t *off) { ... when != off } @ fops0 @ identifier fops; @@ struct file_operations fops = { ... }; @ has_llseek depends on fops0 @ identifier fops0.fops; identifier llseek_f; @@ struct file_operations fops = { ... .llseek = llseek_f, ... }; @ has_read depends on fops0 @ identifier fops0.fops; identifier read_f; @@ struct file_operations fops = { ... .read = read_f, ... }; @ has_write depends on fops0 @ identifier fops0.fops; identifier write_f; @@ struct file_operations fops = { ... .write = write_f, ... }; @ has_open depends on fops0 @ identifier fops0.fops; identifier open_f; @@ struct file_operations fops = { ... .open = open_f, ... }; // use no_llseek if we call nonseekable_open //////////////////////////////////////////// @ nonseekable1 depends on !has_llseek && has_open @ identifier fops0.fops; identifier nso ~= "nonseekable_open"; @@ struct file_operations fops = { ... .open = nso, ... +.llseek = no_llseek, /* nonseekable */ }; @ nonseekable2 depends on !has_llseek @ identifier fops0.fops; identifier open.open_f; @@ struct file_operations fops = { ... .open = open_f, ... +.llseek = no_llseek, /* open uses nonseekable */ }; // use seq_lseek for sequential files ///////////////////////////////////// @ seq depends on !has_llseek @ identifier fops0.fops; identifier sr ~= "seq_read"; @@ struct file_operations fops = { ... .read = sr, ... +.llseek = seq_lseek, /* we have seq_read */ }; // use default_llseek if there is a readdir /////////////////////////////////////////// @ fops1 depends on !has_llseek && !nonseekable1 && !nonseekable2 && !seq @ identifier fops0.fops; identifier readdir_e; @@ // any other fop is used that changes pos struct file_operations fops = { ... .readdir = readdir_e, ... +.llseek = default_llseek, /* readdir is present */ }; // use default_llseek if at least one of read/write touches f_pos ///////////////////////////////////////////////////////////////// @ fops2 depends on !fops1 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @ identifier fops0.fops; identifier read.read_f; @@ // read fops use offset struct file_operations fops = { ... .read = read_f, ... +.llseek = default_llseek, /* read accesses f_pos */ }; @ fops3 depends on !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @ identifier fops0.fops; identifier write.write_f; @@ // write fops use offset struct file_operations fops = { ... .write = write_f, ... + .llseek = default_llseek, /* write accesses f_pos */ }; // Use noop_llseek if neither read nor write accesses f_pos /////////////////////////////////////////////////////////// @ fops4 depends on !fops1 && !fops2 && !fops3 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @ identifier fops0.fops; identifier read_no_fpos.read_f; identifier write_no_fpos.write_f; @@ // write fops use offset struct file_operations fops = { ... .write = write_f, .read = read_f, ... +.llseek = noop_llseek, /* read and write both use no f_pos */ }; @ depends on has_write && !has_read && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @ identifier fops0.fops; identifier write_no_fpos.write_f; @@ struct file_operations fops = { ... .write = write_f, ... +.llseek = noop_llseek, /* write uses no f_pos */ }; @ depends on has_read && !has_write && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @ identifier fops0.fops; identifier read_no_fpos.read_f; @@ struct file_operations fops = { ... .read = read_f, ... +.llseek = noop_llseek, /* read uses no f_pos */ }; @ depends on !has_read && !has_write && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @ identifier fops0.fops; @@ struct file_operations fops = { ... +.llseek = noop_llseek, /* no read or write fn */ }; ===== End semantic patch ===== Signed-off-by: Arnd Bergmann <arnd@arndb.de> Cc: Julia Lawall <julia@diku.dk> Cc: Christoph Hellwig <hch@infradead.org>
2010-08-16 00:52:59 +08:00
.llseek = noop_llseek,
};
void hid_debug_register(struct hid_device *hdev, const char *name)
{
hdev->debug_dir = debugfs_create_dir(name, hid_debug_root);
hdev->debug_rdesc = debugfs_create_file("rdesc", 0400,
hdev->debug_dir, hdev, &hid_debug_rdesc_fops);
hdev->debug_events = debugfs_create_file("events", 0400,
hdev->debug_dir, hdev, &hid_debug_events_fops);
hdev->debug = 1;
}
void hid_debug_unregister(struct hid_device *hdev)
{
hdev->debug = 0;
wake_up_interruptible(&hdev->debug_wait);
debugfs_remove(hdev->debug_rdesc);
debugfs_remove(hdev->debug_events);
debugfs_remove(hdev->debug_dir);
}
void hid_debug_init(void)
{
hid_debug_root = debugfs_create_dir("hid", NULL);
}
void hid_debug_exit(void)
{
debugfs_remove_recursive(hid_debug_root);
}