In preparation for destroying the line discipline instance on hangup,
move tty_ldisc_kill() to eliminate needless forward declarations.
No functional change.
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In preparation of destroying line discipline on hangup, fix
ldisc core operations to properly handle when the tty's ldisc is
NULL.
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
tty file_operations (read/write/ioctl) wait for the ldisc reference
indefinitely (until ldisc lifetime events, such as hangup or TIOCSETD,
finish). Since hangup now destroys the ldisc and does not instance
another copy, file_operations must now be prepared to receive a NULL
ldisc reference from tty_ldisc_ref_wait():
CPU 0 CPU 1
----- -----
(*f_op->read)() => tty_read()
__tty_hangup()
...
f_op = &hung_up_tty_fops;
...
tty_ldisc_hangup()
tty_ldisc_lock()
tty_ldisc_kill()
tty->ldisc = NULL
tty_ldisc_unlock()
ld = tty_ldisc_ref_wait()
/* ld == NULL */
Instead, the action taken now is to return the same value as if the
tty had been hungup a moment earlier:
CPU 0 CPU 1
----- -----
__tty_hangup()
...
f_op = &hung_up_tty_fops;
(*f_op->read)() => hung_up_tty_read()
return 0;
...
tty_ldisc_hangup()
tty_ldisc_lock()
tty_ldisc_kill()
tty->ldisc = NULL
tty_ldisc_unlock()
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
tty_ldisc_kill() sets tty->ldisc to NULL; _not_ to N_TTY with a valid
but unopened ldisc. Fix function header documentation.
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
tty_ldisc_get() returns ERR_PTR() values if unsuccessful, not NULL;
fix function header documentation.
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
After the ldisc is released, but before the tty is destroyed, the termios
is saved (in tty_free_termios()); this termios is restored if a new
tty is created on next open(). However, the line discipline is always
reset, which is not obvious in the current method. Instead, reset
as part of the restore.
Restore the original line discipline, which may not have been N_TTY.
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The chars_in_buffer() line discipline method serves no functional
purpose, other than as a (dubious) debugging aid for mostly bit-rotting
drivers. Despite being documented as an optional method, every caller
is unconditionally executed (although conditionally compiled).
Furthermore, direct tty->ldisc access without an ldisc ref is unsafe.
Lastly, N_TTY's chars_in_buffer() has warned of removal since 3.12.
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The N_NCI ldisc does not define a flush_buffer() ldisc method, so
the check when opening the ldisc is always false.
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
As the #warning indicates, the open-coded ldisc reset was always not ok.
Not only is this code long dead, but now it would have no effect as
the ldisc is destroyed when this driver's close() method returns; remove.
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The open-coded tty_wakeup()s are attempts to workaround fixed bugs
in the line discipline write_wakeup() method. Replace with tty_wakeup().
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Extract the driver lookup and reopen-or-initialize logic into helper
function tty_open_by_driver(). No functional change.
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Evaluate the conditions which prevent this tty being the controlling
terminal in one place, just before setting the controlling terminal.
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The tty lock/unlock code does not belong in the special lockfunc section
which is treated specially by stack backtraces.
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The tty core invokes the optional driver shutdown() just before
the optional driver remove() (shutdown() has access to the termios
and remove() does not). Because pty drivers must prevent the default
remove() action, the Unix98 pty drivers define a dummy remove() function.
Instead, release the slave index in the remove() method and delete the
optional shutdown() method.
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
tty_driver_remove_tty() is only local-scope; declare as static.
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
tty_init_termios() never returns an error; re-declare as void. Remove
unnecessary error handling from callers. Remove extern declarations
of tty_free_termios() and free_tty_struct() and re-declare in file
scope.
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Acked-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
free_tty_struct() is never called with NULL tty; the two call sites
would already have faulted on earlier access.
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
release_tty() leaks the ldisc instance when called directly (rather
than when releasing the file descriptor from tty_release()).
Since tty_ldisc_release() clears tty->ldisc, releasing the ldisc
instance at tty teardown if tty->ldisc is non-null is not in danger
of double-releasing the ldisc.
Remove deinitialize_tty_struct() now that free_tty_struct() always
performs the tty_ldisc_deinit().
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
gcc warns quite a bit about values returned from allocate_resources()
in cpufreq-dt.c:
cpufreq-dt.c: In function 'cpufreq_init':
cpufreq-dt.c:327:6: error: 'cpu_dev' may be used uninitialized in this function [-Werror=maybe-uninitialized]
cpufreq-dt.c:197:17: note: 'cpu_dev' was declared here
cpufreq-dt.c:376:2: error: 'cpu_clk' may be used uninitialized in this function [-Werror=maybe-uninitialized]
cpufreq-dt.c:199:14: note: 'cpu_clk' was declared here
cpufreq-dt.c: In function 'dt_cpufreq_probe':
cpufreq-dt.c:461:2: error: 'cpu_clk' may be used uninitialized in this function [-Werror=maybe-uninitialized]
cpufreq-dt.c:447:14: note: 'cpu_clk' was declared here
The problem is that it's slightly hard for gcc to follow return
codes across PTR_ERR() calls.
This patch uses explicit assignments to the "ret" variable to make
it easier for gcc to verify that the code is actually correct,
without the need to add a bogus initialization.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
There are two definitions of pxa_cpufreq_change_voltage, with slightly
different prototypes after one of them had its argument marked 'const'.
Now the other one (for !CONFIG_REGULATOR) produces a harmless warning:
drivers/cpufreq/pxa2xx-cpufreq.c: In function 'pxa_set_target':
drivers/cpufreq/pxa2xx-cpufreq.c:291:36: warning: passing argument 1 of 'pxa_cpufreq_change_voltage' discards 'const' qualifier from pointer target type [-Wdiscarded-qualifiers]
ret = pxa_cpufreq_change_voltage(&pxa_freq_settings[idx]);
^
drivers/cpufreq/pxa2xx-cpufreq.c:205:12: note: expected 'struct pxa_freqs *' but argument is of type 'const struct pxa_freqs *'
static int pxa_cpufreq_change_voltage(struct pxa_freqs *pxa_freq)
^
This changes the prototype in the same way as the other, which
avoids the warning.
Fixes: 03c2299063 (cpufreq: pxa: make pxa_freqs arrays const)
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Cc: 4.2+ <stable@vger.kernel.org> # 4.2+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The APM emulation code does multiple things, and some of them depend on
PM_SLEEP, while the battery management does not. However, selecting
the symbol like SHARPSL_PM does causes a Kconfig warning:
warning: (SHARPSL_PM && PMAC_APM_EMU) selects APM_EMULATION which has unmet direct dependencies (PM && SYS_SUPPORTS_APM_EMULATION)
From all I can tell, this is completely harmless, and we can simply allow
APM_EMULATION to be enabled here, even if PM is not.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Currently next_policy() explicitly checks if a policy is the last
policy in the cpufreq_policy_list. Use the standard list_is_last
primitive instead.
Signed-off-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
This was found with the -RT patch enabled, but the fix should apply to
non-RT also.
Used multi_v7_defconfig+PREEMPT_RT_FULL=y and this caused a compilation
warning without this fix:
../drivers/cpuidle/coupled.c:122:21: warning: 'cpuidle_coupled_lock'
defined but not used [-Wunused-variable]
Signed-off-by: Anders Roxell <anders.roxell@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Kevin Hilman <khilman@baylibre.com>
Signed-off-by: Moritz Fischer <moritz.fischer@ettus.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
We must preserve the same order of how we acquire and release the lock for
genpd, as otherwise we may encounter deadlocks.
The power on phase of a genpd starts by acquiring its lock. Then it walks
the hierarchy of its parent domains to be able to power on these first, as
per design of genpd.
From a locking perspective this means the locks of the parents becomes
acquired after the lock of the subdomain.
Let's fix pm_genpd_add|remove_subdomain() to maintain the same order of
acquiring/releasing the genpd lock as being applied in the power on/off
sequence.
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
This fixes existing tests broken by barrier rework,
and adds some new tests.
Plus, there's a fix for an old bug in virtio-pci.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
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Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost
Pull virtio tests and fixes from Michael Tsirkin:
"This fixes existing tests broken by barrier rework, and adds some new
tests.
Plus, there's a fix for an old bug in virtio-pci"
* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost:
tools/virtio: add ringtest utilities
sh: fix smp_store_mb for !SMP
tools/virtio: use virt_xxx barriers
virtio_pci: fix use after free on release
This reverts commit 5bdb102b3f.
Brian Norris <computersforpeace@gmail.com> is reporting:
Ralf,
Please revert this and send it to Linus (or else, I can send it myself).
This is causing build failures, because I didn't take the rest of
Simon's series yet.
drivers/mtd/bcm63xxpart.c: In function 'bcm63xx_parse_cfe_partitions':
drivers/mtd/bcm63xxpart.c:93:2: error: implicit declaration of function
'bcm63xx_nvram_get_psi_size' [-Werror=implicit-function-declaration]
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
References: https://www.linux-mips.org/cgi-bin/mesg.cgi?a=linux-mips&i=20160126191607.GA111152%40google.com
- Ensure we don't access PMU registers of the PMU is not implemented
(fixes booting under QEMU)
- Fix BUG_ON triggered during module loading with DEBUG_SET_MODULE_RONX
- Ensure the kasan zero page is read-only
- Hide __efistub_ symbol aliases from kallsyms, since they otherwise
confuse the backtrace code
- Ensure !PTE_WRITE kernel ptes are marked as read-only
- defconfig updates based on requests and patches on the list
- Other minor fixes (typos, build system)
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Merge tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux
Pull arm64 fixes from Will Deacon:
"The main thing here is to get us booting under qemu again after it
turned out that not all of the PMU registers are emulated there,
causing us to die early in boot.
- Ensure we don't access PMU registers of the PMU is not implemented
(fixes booting under QEMU)
- Fix BUG_ON triggered during module loading with DEBUG_SET_MODULE_RONX
- Ensure the kasan zero page is read-only
- Hide __efistub_ symbol aliases from kallsyms, since they otherwise
confuse the backtrace code
- Ensure !PTE_WRITE kernel ptes are marked as read-only
- defconfig updates based on requests and patches on the list
- Other minor fixes (typos, build system)"
* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
arm64: mm: avoid calling apply_to_page_range on empty range
arm64: defconfig: updates for 4.5
arm64: errata: Add -mpc-relative-literal-loads to build flags
Eliminate the .eh_frame sections from the aarch64 vmlinux and kernel modules
arm64: Fix an enum typo in mm/dump.c
arm64: Honour !PTE_WRITE in set_pte_at() for kernel mappings
arm64: kernel: fix architected PMU registers unconditional access
arm64: kasan: ensure that the KASAN zero page is mapped read-only
arm64: hide __efistub_ aliases from kallsyms
The email address <ao2@amarulasolutions.com> is not active anymore, use
Antonio's personal email address <ao2@ao2.it> in case someone wants to
get in touch for the code wrote for Amarula Solutions.
Signed-off-by: Antonio Ospite <ao2@ao2.it>
Cc: Michael Trimarchi <michael@amarulasolutions.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Using iommu_present() to determine whether an IOMMU group is real or
fake has some problems. First, apparently Power systems don't
register an IOMMU on the device bus, so the groups and containers get
marked as noiommu and then won't bind to their actual IOMMU driver.
Second, I expect we'll run into the same issue as we try to support
vGPUs through vfio, since they're likely to emulate this behavior of
creating an IOMMU group on a virtual device and then providing a vfio
IOMMU backend tailored to the sort of isolation they provide, which
won't necessarily be fully compatible with the IOMMU API.
The solution here is to use the existing iommudata interface to IOMMU
groups, which allows us to easily identify the fake groups we've
created for noiommu purposes. The iommudata we set is purely
arbitrary since we're only comparing the address, so we use the
address of the noiommu switch itself.
Reported-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Tested-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Tested-by: Anatoly Burakov <anatoly.burakov@intel.com>
Tested-by: Santosh Shukla <sshukla@mvista.com>
Fixes: 03a76b60f8 ("vfio: Include No-IOMMU mode")
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Properly setup the DFS divider for DP audio for DCE4.1.
Signed-off-by: Slava Grigorev <slava.grigorev@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org
Move encoding of DFS (digital frequency synthesizer) divider into a
separate function and improve calculation precision.
Signed-off-by: Slava Grigorev <slava.grigorev@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org
This is preparation for the fixes in the following patches.
Signed-off-by: Slava Grigorev <slava.grigorev@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org
Fix firmware init on Stoney when powerplay is enabled.
Signed-off-by: Rex Zhu <Rex.Zhu@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Before this patch, a process with some permissive seccomp filter
that was applied by root without NO_NEW_PRIVS was able to add
more filters to itself without setting NO_NEW_PRIVS by setting
the new filter from a throwaway thread with NO_NEW_PRIVS.
Signed-off-by: Jann Horn <jann@thejh.net>
Cc: stable@vger.kernel.org
Signed-off-by: Kees Cook <keescook@chromium.org>
On my bigger s390 systems I always get "Out of memory.
ODEBUG disabled". Since the number of objects is needed at
compile time, we can not change the size dynamically before
the caches etc are available. Doubling the size seems to
do the trick. Since it is init data it will be freed anyway,
this should be ok.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Link: http://lkml.kernel.org/r/1453905478-13409-1-git-send-email-borntraeger@de.ibm.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Let cleancache_fs_enabled() call cleancache_fs_enabled_mapping()
directly.
Remove redundant variable ret in cleancache_get_page().
Signed-off-by: Chen Gang <gang.chen.5i5j@gmail.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
The cleancache_ops structure is never modified, so declare it as const.
Done with the help of Coccinelle.
Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
If the mount phase is not finished, we can't update the sysfs files.
Reported-by: Chris Mason <clm@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
Atmel AIC has common structure for SMR (Source Mode Register).
bit[6:5] Interrupt source type
bit[2:0] Priority level
Other bits are unused.
To update new priority value, bit[2:0] should be cleared first and then
new priority level can be written. However, aic_common_set_priority()
helper clears source type bits instead of priority bits.
This patch fixes wrong mask bit operation.
Fixes: b1479ebb77 "irqchip: atmel-aic: Add atmel AIC/AIC5 drivers"
Signed-off-by: Milo Kim <milo.kim@ti.com>
Acked-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Ludovic Desroches <ludovic.desroches@atmel.com>
Cc: Nicholas Ferre <nicolas.ferre@atmel.com>
Cc: stable@vger.kernel.org #v3.17+
Link: http://lkml.kernel.org/r/1452669592-3401-2-git-send-email-milo.kim@ti.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
commit 0ff53d0964 sets the next tick interrupt to the last jiffies update,
i.e. in the past, because the forward operation is invoked before the set
operation. There is no resulting damage (yet), but we get an extra pointless
tick interrupt.
Revert the order so we get the next tick interrupt in the future.
Fixes: commit 0ff53d0964 "tick: sched: Force tick interrupt and get rid of softirq magic"
Signed-off-by: Wanpeng Li <wanpeng.li@hotmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/1453893967-3458-1-git-send-email-wanpeng.li@hotmail.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
As the function documentation for tty_ldisc_ref_wait() notes, it is
only callable from a tty file_operations routine; otherwise there
is no guarantee the ref won't be NULL.
The key difference with the VT's paste_selection() is that is an ioctl,
where __speakup_paste_selection() is completely async kworker, kicked
off from interrupt context.
Fixes: 28a821c306 ("Staging: speakup: Update __speakup_paste_selection()
tty (ab)usage to match vt")
Cc: <stable@vger.kernel.org>
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Although n_tty_check_unthrottle() has a valid ldisc reference (since
the tty core gets the ldisc ref in tty_read() before calling the line
discipline read() method), it does not have a valid ldisc reference to
the "other" pty of a pty pair. Since getting an ldisc reference for
tty->link essentially open-codes tty_wakeup(), just replace with the
equivalent tty_wakeup().
Cc: <stable@vger.kernel.org>
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
ioctl(TIOCGETD) retrieves the line discipline id directly from the
ldisc because the line discipline id (c_line) in termios is untrustworthy;
userspace may have set termios via ioctl(TCSETS*) without actually
changing the line discipline via ioctl(TIOCSETD).
However, directly accessing the current ldisc via tty->ldisc is
unsafe; the ldisc ptr dereferenced may be stale if the line discipline
is changing via ioctl(TIOCSETD) or hangup.
Wait for the line discipline reference (just like read() or write())
to retrieve the "current" line discipline id.
Cc: <stable@vger.kernel.org>
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
A small window exists where a tty reopen will observe the tty
just prior to imminent teardown (tty->count == 0); in this case, open()
returns EIO to userspace.
Instead, retry the open after checking for signals and yielding;
this interruptible retry loop allows teardown to commence and initialize
a new tty on retry. Never retry the BSD master pty reopen; there is no
guarantee the pty pair teardown is imminent since the slave file
descriptors may remain open indefinitely.
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Cc: stable <stable@vger.kernel.org> # 4.4
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Peter Hurley