Commit Graph

87 Commits

Author SHA1 Message Date
Dan Carpenter 432798195b uio: Fix an Oops on load
I was trying to solve a double free but I introduced a more serious
NULL dereference bug.  The problem is that if there is an IRQ which
triggers immediately, then we need "info->uio_dev" but it's not set yet.

This patch puts the original initialization back to how it was and just
sets info->uio_dev to NULL on the error path so it should solve both
the Oops and the double free.

Fixes: f019f07ecf ("uio: potential double frees if __uio_register_device() fails")
Reported-by: Mathias Thore <Mathias.Thore@infinera.com>
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Cc: stable <stable@vger.kernel.org>
Tested-by: Mathias Thore <Mathias.Thore@infinera.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-11-11 09:21:46 -08:00
Wei Yongjun 6011002c15 uio: make symbol 'uio_class_registered' static
Fixes the following sparse warning:

drivers/uio/uio.c:277:6: warning:
 symbol 'uio_class_registered' was not declared. Should it be static?

Fixes: ae61cf5b99 ("uio: ensure class is registered before devices")
Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-10-02 15:38:14 -07:00
Stephen Hemminger bfddabfa23 uio: introduce UIO_MEM_IOVA
Introduce the concept of mapping physical memory locations that
are normal memory. The new type UIO_MEM_IOVA are similar to
existing UIO_MEM_PHYS but the backing memory is not marked as uncached.

Also, indent related switch to the currently used style.

Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-25 20:33:24 +02:00
Souptick Joarder 79c6f4b84b uio: convert to vm_fault_t
As part of commit 9b85e95a30 ("uio: Change return
type to vm_fault_t") in 4.19-rc1, this conversion
was missed. Now converted 'ret' to vm_fault_t type.

Signed-off-by: Souptick Joarder <jrdr.linux@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-12 09:46:46 +02:00
Alexandre Belloni ae61cf5b99 uio: ensure class is registered before devices
When both uio and the uio drivers are built in the kernel, it is possible
for a driver to register devices before the uio class is registered.

This may result in a NULL pointer dereference later on in
get_device_parent() when accessing the class glue_dirs spinlock.

The trace looks like that:

Unable to handle kernel NULL pointer dereference at virtual address 00000140
[...]
[<ffff0000089cc234>] _raw_spin_lock+0x14/0x48
[<ffff0000084f56bc>] device_add+0x154/0x6a0
[<ffff0000084f5e48>] device_create_groups_vargs+0x120/0x128
[<ffff0000084f5edc>] device_create+0x54/0x60
[<ffff0000086e72c0>] __uio_register_device+0x120/0x4a8
[<ffff000008528b7c>] jaguar2_pci_probe+0x2d4/0x558
[<ffff0000083fc18c>] local_pci_probe+0x3c/0xb8
[<ffff0000083fd81c>] pci_device_probe+0x11c/0x180
[<ffff0000084f88bc>] driver_probe_device+0x22c/0x2d8
[<ffff0000084f8a24>] __driver_attach+0xbc/0xc0
[<ffff0000084f69fc>] bus_for_each_dev+0x4c/0x98
[<ffff0000084f81b8>] driver_attach+0x20/0x28
[<ffff0000084f7d08>] bus_add_driver+0x1b8/0x228
[<ffff0000084f93c0>] driver_register+0x60/0xf8
[<ffff0000083fb918>] __pci_register_driver+0x40/0x48

Return EPROBE_DEFER in that case so the driver can register the device
later.

Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-12 09:46:46 +02:00
Linus Torvalds 1d0926e99d Char/Misc fix for 4.19-rc1
Here is a single UIO fix that I forgot to send before 4.18-final came
 out.  It reverts a UIO patch that went in the 4.18 development window
 that was causing problems.
 
 This patch has been in linux-next for a while with no problems, I just
 forgot to send it earlier, or as part of the larger char/misc patch
 series from yesterday, my fault.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'char-misc-4.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc

Pull UIO fix from Greg KH:
 "Here is a single UIO fix that I forgot to send before 4.18-final came
  out. It reverts a UIO patch that went in the 4.18 development window
  that was causing problems.

  This patch has been in linux-next for a while with no problems, I just
  forgot to send it earlier, or as part of the larger char/misc patch
  series from yesterday, my fault"

* tag 'char-misc-4.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc:
  Revert "uio: use request_threaded_irq instead"
2018-08-19 09:30:44 -07:00
Xiubo Li 3d27c4de8d Revert "uio: use request_threaded_irq instead"
Since mutex lock in irq hanler is useless currently, here will
remove it together with it.

This reverts commit 9421e45f5f.

Reported-by: james.r.harris@intel.com
CC: Ahsan Atta <ahsan.atta@intel.com>
Signed-off-by: Xiubo Li <xiubli@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-08-12 17:30:58 +02:00
Dan Carpenter f019f07ecf uio: potential double frees if __uio_register_device() fails
The uio_unregister_device() function assumes that if "info->uio_dev" is
non-NULL that means "info" is fully allocated.  Setting info->uio_de
has to be the last thing in the function.

In the current code, if request_threaded_irq() fails then we return with
info->uio_dev set to non-NULL but info is not fully allocated and it can
lead to double frees.

Fixes: beafc54c4e ("UIO: Add the User IO core code")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-08-02 10:42:25 +02:00
Xiubo Li b34e9a15b3 uio: fix possible circular locking dependency
The call trace:
XXX/1910 is trying to acquire lock:
 (&mm->mmap_sem){++++++}, at: [<ffffffff97008c87>] might_fault+0x57/0xb0

but task is already holding lock:
 (&idev->info_lock){+.+...}, at: [<ffffffffc0638a06>] uio_write+0x46/0x130 [uio]

which lock already depends on the new lock.

the existing dependency chain (in reverse order) is:

-> #1 (&idev->info_lock){+.+...}:
       [<ffffffff96f31fc9>] lock_acquire+0x99/0x1e0
       [<ffffffff975edad3>] mutex_lock_nested+0x93/0x410
       [<ffffffffc063873d>] uio_mmap+0x2d/0x170 [uio]
       [<ffffffff97016b58>] mmap_region+0x428/0x650
       [<ffffffff97017138>] do_mmap+0x3b8/0x4e0
       [<ffffffff96ffaba3>] vm_mmap_pgoff+0xd3/0x120
       [<ffffffff97015261>] SyS_mmap_pgoff+0x1f1/0x270
       [<ffffffff96e387c2>] SyS_mmap+0x22/0x30
       [<ffffffff975ff315>] system_call_fastpath+0x1c/0x21

-> #0 (&mm->mmap_sem){++++++}:
       [<ffffffff96f30e9c>] __lock_acquire+0xdac/0x15f0
       [<ffffffff96f31fc9>] lock_acquire+0x99/0x1e0
       [<ffffffff97008cb4>] might_fault+0x84/0xb0
       [<ffffffffc0638a74>] uio_write+0xb4/0x130 [uio]
       [<ffffffff9706ffa3>] vfs_write+0xc3/0x1f0
       [<ffffffff97070e2a>] SyS_write+0x8a/0x100
       [<ffffffff975ff315>] system_call_fastpath+0x1c/0x21

other info that might help us debug this:
 Possible unsafe locking scenario:
       CPU0                    CPU1
       ----                    ----
  lock(&idev->info_lock);
                               lock(&mm->mmap_sem);
                               lock(&idev->info_lock);
  lock(&mm->mmap_sem);

 *** DEADLOCK ***
1 lock held by XXX/1910:
 #0:  (&idev->info_lock){+.+...}, at: [<ffffffffc0638a06>] uio_write+0x46/0x130 [uio]

stack backtrace:
CPU: 0 PID: 1910 Comm: XXX Kdump: loaded Not tainted #1
Hardware name: VMware, Inc. VMware Virtual Platform/440BX Desktop Reference Platform, BIOS 6.00 05/19/2017
Call Trace:
 [<ffffffff975e9211>] dump_stack+0x19/0x1b
 [<ffffffff975e260a>] print_circular_bug+0x1f9/0x207
 [<ffffffff96f2f6a7>] check_prevs_add+0x957/0x960
 [<ffffffff96f30e9c>] __lock_acquire+0xdac/0x15f0
 [<ffffffff96f2fb19>] ? mark_held_locks+0xb9/0x140
 [<ffffffff96f31fc9>] lock_acquire+0x99/0x1e0
 [<ffffffff97008c87>] ? might_fault+0x57/0xb0
 [<ffffffff97008cb4>] might_fault+0x84/0xb0
 [<ffffffff97008c87>] ? might_fault+0x57/0xb0
 [<ffffffffc0638a74>] uio_write+0xb4/0x130 [uio]
 [<ffffffff9706ffa3>] vfs_write+0xc3/0x1f0
 [<ffffffff9709349c>] ? fget_light+0xfc/0x510
 [<ffffffff97070e2a>] SyS_write+0x8a/0x100
 [<ffffffff975ff315>] system_call_fastpath+0x1c/0x21

Signed-off-by: Xiubo Li <xiubli@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-08-02 10:14:26 +02:00
Hailong Liu e7de2590f1 uio: fix wrong return value from uio_mmap()
uio_mmap has multiple fail paths to set return value to nonzero then
goto out. However, it always returns *0* from the *out* at end, and
this will mislead callers who check the return value of this function.

Fixes: 57c5f4df0a ("uio: fix crash after the device is unregistered")
CC: Xiubo Li <xiubli@redhat.com>
Signed-off-by: Hailong Liu <liu.hailong6@zte.com.cn>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Jiang Biao <jiang.biao2@zte.com.cn>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-07-21 08:45:24 +02:00
Stephen Hemminger fbb5858c14 uio: add SPDX license tag
Replace short statement in comment with proper SPDX
license tag.

Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-07-21 08:44:08 +02:00
Xiubo Li 57c5f4df0a uio: fix crash after the device is unregistered
For the target_core_user use case, after the device is unregistered
it maybe still opened in user space, then the kernel will crash, like:

[  251.163692] BUG: unable to handle kernel NULL pointer dereference at 0000000000000008
[  251.163820] IP: [<ffffffffc0736213>] show_name+0x23/0x40 [uio]
[  251.163965] PGD 8000000062694067 PUD 62696067 PMD 0
[  251.164097] Oops: 0000 [#1] SMP
...
[  251.165605]  e1000 mptscsih mptbase drm_panel_orientation_quirks dm_mirror dm_region_hash dm_log dm_mod
[  251.166014] CPU: 0 PID: 13380 Comm: tcmu-runner Kdump: loaded Not tainted 3.10.0-916.el7.test.x86_64 #1
[  251.166381] Hardware name: VMware, Inc. VMware Virtual Platform/440BX Desktop Reference Platform, BIOS 6.00 05/19/2017
[  251.166747] task: ffff971eb91db0c0 ti: ffff971e9e384000 task.ti: ffff971e9e384000
[  251.167137] RIP: 0010:[<ffffffffc0736213>]  [<ffffffffc0736213>] show_name+0x23/0x40 [uio]
[  251.167563] RSP: 0018:ffff971e9e387dc8  EFLAGS: 00010282
[  251.167978] RAX: 0000000000000000 RBX: ffff971e9e3f8000 RCX: ffff971eb8368d98
[  251.168408] RDX: ffff971e9e3f8000 RSI: ffffffffc0738084 RDI: ffff971e9e3f8000
[  251.168856] RBP: ffff971e9e387dd0 R08: ffff971eb8bc0018 R09: 0000000000000000
[  251.169296] R10: 0000000000001000 R11: ffffffffa09d444d R12: ffffffffa1076e80
[  251.169750] R13: ffff971e9e387f18 R14: 0000000000000001 R15: ffff971e9cfb1c80
[  251.170213] FS:  00007ff37d175880(0000) GS:ffff971ebb600000(0000) knlGS:0000000000000000
[  251.170693] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  251.171248] CR2: 0000000000000008 CR3: 00000000001f6000 CR4: 00000000003607f0
[  251.172071] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[  251.172640] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[  251.173236] Call Trace:
[  251.173789]  [<ffffffffa0c9b2d3>] dev_attr_show+0x23/0x60
[  251.174356]  [<ffffffffa0f561b2>] ? mutex_lock+0x12/0x2f
[  251.174892]  [<ffffffffa0ac6d9f>] sysfs_kf_seq_show+0xcf/0x1f0
[  251.175433]  [<ffffffffa0ac54e6>] kernfs_seq_show+0x26/0x30
[  251.175981]  [<ffffffffa0a63be0>] seq_read+0x110/0x3f0
[  251.176609]  [<ffffffffa0ac5d45>] kernfs_fop_read+0xf5/0x160
[  251.177158]  [<ffffffffa0a3d3af>] vfs_read+0x9f/0x170
[  251.177707]  [<ffffffffa0a3e27f>] SyS_read+0x7f/0xf0
[  251.178268]  [<ffffffffa0f648af>] system_call_fastpath+0x1c/0x21
[  251.178823] Code: 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 55 48 89 e5 53 48 89 d3 e8 7e 96 56 e0 48 8b 80 d8 02 00 00 48 89 df 48 c7 c6 84 80 73 c0 <48> 8b 50 08 31 c0 e8 e2 67 44 e0 5b 48 98 5d c3 0f 1f 00 66 2e
[  251.180115] RIP  [<ffffffffc0736213>] show_name+0x23/0x40 [uio]
[  251.180820]  RSP <ffff971e9e387dc8>
[  251.181473] CR2: 0000000000000008

CC: Hamish Martin <hamish.martin@alliedtelesis.co.nz>
CC: Mike Christie <mchristi@redhat.com>
Reviewed-by: Hamish Martin <hamish.martin@alliedtelesis.co.nz>
Signed-off-by: Xiubo Li <xiubli@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-07-07 16:57:35 +02:00
Xiubo Li 543af5861f uio: change to use the mutex lock instead of the spin lock
We are hitting a regression with the following commit:

commit a93e7b3315
Author: Hamish Martin <hamish.martin@alliedtelesis.co.nz>
Date:   Mon May 14 13:32:23 2018 +1200

    uio: Prevent device destruction while fds are open

The problem is the addition of spin_lock_irqsave in uio_write. This
leads to hitting  uio_write -> copy_from_user -> _copy_from_user ->
might_fault and the logs filling up with sleeping warnings.

I also noticed some uio drivers allocate memory, sleep, grab mutexes
from callouts like open() and release and uio is now doing
spin_lock_irqsave while calling them.

Reported-by: Mike Christie <mchristi@redhat.com>
CC: Hamish Martin <hamish.martin@alliedtelesis.co.nz>
Reviewed-by: Hamish Martin <hamish.martin@alliedtelesis.co.nz>
Signed-off-by: Xiubo Li <xiubli@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-07-07 16:57:35 +02:00
Xiubo Li 9421e45f5f uio: use request_threaded_irq instead
Prepraing for changing to use mutex lock.

Signed-off-by: Xiubo Li <xiubli@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-07-07 16:57:35 +02:00
Hamish Martin a93e7b3315 uio: Prevent device destruction while fds are open
Prevent destruction of a uio_device while user space apps hold open
file descriptors to that device. Further, access to the 'info' member
of the struct uio_device is protected by spinlock. This is to ensure
stale pointers to data not under control of the UIO subsystem are not
dereferenced.

Signed-off-by: Hamish Martin <hamish.martin@alliedtelesis.co.nz>
Reviewed-by: Chris Packham <chris.packham@alliedtelesis.co.nz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-14 16:16:35 +02:00
Hamish Martin 81daa406c2 uio: Reduce return paths from uio_write()
Drive all return paths for uio_write() through a single block at the
end of the function.

Signed-off-by: Hamish Martin <hamish.martin@alliedtelesis.co.nz>
Reviewed-by: Chris Packham <chris.packham@alliedtelesis.co.nz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-14 16:12:47 +02:00
Souptick Joarder 9b85e95a30 uio: Change return type to vm_fault_t
Use new return type vm_fault_t for fault handler
in struct vm_operations_struct. For now, this is
just documenting that the function returns a VM_
FAULT value rather than an errno.  Once all inst
ances are converted, vm_fault_t will become a di
stinct type.

Reference - 1c8f422059 ("mm: change return type
to vm_fault_t")

Signed-off-by: Souptick Joarder <jrdr.linux@gmail.com>
Reviewed-by: Matthew Wilcox <mawilcox@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-04-23 13:31:27 +02:00
Linus Torvalds a9a08845e9 vfs: do bulk POLL* -> EPOLL* replacement
This is the mindless scripted replacement of kernel use of POLL*
variables as described by Al, done by this script:

    for V in IN OUT PRI ERR RDNORM RDBAND WRNORM WRBAND HUP RDHUP NVAL MSG; do
        L=`git grep -l -w POLL$V | grep -v '^t' | grep -v /um/ | grep -v '^sa' | grep -v '/poll.h$'|grep -v '^D'`
        for f in $L; do sed -i "-es/^\([^\"]*\)\(\<POLL$V\>\)/\\1E\\2/" $f; done
    done

with de-mangling cleanups yet to come.

NOTE! On almost all architectures, the EPOLL* constants have the same
values as the POLL* constants do.  But they keyword here is "almost".
For various bad reasons they aren't the same, and epoll() doesn't
actually work quite correctly in some cases due to this on Sparc et al.

The next patch from Al will sort out the final differences, and we
should be all done.

Scripted-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-02-11 14:34:03 -08:00
Al Viro afc9a42b74 the rest of drivers/*: annotate ->poll() instances
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-11-28 11:06:58 -05:00
Suman Anna 0d83539092 uio: fix incorrect memory leak cleanup
Commit 75f0aef622 ("uio: fix memory leak") has fixed up some
memory leaks during the failure paths of the addition of uio
attributes, but still is not correct entirely. A kobject_uevent()
failure still needs a kobject_put() and the kobject container
structure allocation failure before the kobject_init() doesn't
need a kobject_put(). Fix this properly.

Fixes: 75f0aef622 ("uio: fix memory leak")
Signed-off-by: Suman Anna <s-anna@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-16 23:06:41 +02:00
Michal Sojka 171058fb08 uio: Allow handling of non page-aligned memory regions
Since commit b655028795 ("uio: we cannot mmap unaligned page
contents") addresses and sizes of UIO memory regions must be
page-aligned. If the address in the BAR register is not
page-aligned (which is the case of the mf264 card), the mentioned
commit forces the UIO driver to round the address down to the page
size. Then, there is no easy way for user-space to learn the offset of
the actual memory region within the page, because the offset seen in
/sys/class/uio/uio?/maps/map?/offset is calculated from the rounded
address and thus it is always zero.

Fix that problem by including the offset in struct uio_mem. UIO
drivers can set this field and userspace can read its value from
/sys/class/uio/uio?/maps/map?/offset.

The following commits update the uio_mf264 driver to set this new offs
field.

Drivers for hardware with page-aligned BARs need not to be modified
provided that they initialize struct uio_info (which contains uio_mem)
with zeros.

Signed-off-by: Michal Sojka <sojkam1@fel.cvut.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-04-08 18:13:27 +02:00
Ingo Molnar 174cd4b1e5 sched/headers: Prepare to move signal wakeup & sigpending methods from <linux/sched.h> into <linux/sched/signal.h>
Fix up affected files that include this signal functionality via sched.h.

Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-03-02 08:42:32 +01:00
Dave Jiang 11bac80004 mm, fs: reduce fault, page_mkwrite, and pfn_mkwrite to take only vmf
->fault(), ->page_mkwrite(), and ->pfn_mkwrite() calls do not need to
take a vma and vmf parameter when the vma already resides in vmf.

Remove the vma parameter to simplify things.

[arnd@arndb.de: fix ARM build]
  Link: http://lkml.kernel.org/r/20170125223558.1451224-1-arnd@arndb.de
Link: http://lkml.kernel.org/r/148521301778.19116.10840599906674778980.stgit@djiang5-desk3.ch.intel.com
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Cc: Theodore Ts'o <tytso@mit.edu>
Cc: Darrick J. Wong <darrick.wong@oracle.com>
Cc: Matthew Wilcox <mawilcox@microsoft.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Jan Kara <jack@suse.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-02-24 17:46:54 -08:00
Dan Carpenter 0320a278b9 uio: add missing error codes
My static checker complains that "ret" could be uninitialized at the
end, which is true but it's more likely that it would be set to zero.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-05-01 14:11:12 -07:00
Michal Hocko edce5e6f33 uio: fix false positive __might_sleep warning splat
Andy has reported a __might_sleep warning
[ 5174.883617] WARNING: CPU: 0 PID: 1532 at
/home/agrover/git/kernel/kernel/sched/core.c:7389 __might_sleep+0x7d/0x90()
[ 5174.884407] do not call blocking ops when !TASK_RUNNING; state=1 set at [<ffffffffa02a5821>] uio_read+0x91/0x170 [uio]
[ 5174.885198] Modules linked in: tcm_loop target_core_user uio target_core_pscsi target_core_file target_core_iblock iscsi_target_mod  target_core_mod uinput fuse nfsv3 nfs_acl nfs lockd grace fscache sunrpc microcode i2c_piix4 virtio_balloon i2c_core xfs libcrc32c crc32c_intel  virtio_net virtio_blk
[ 5174.887351] CPU: 0 PID: 1532 Comm: tcmu-runner Not tainted 4.2.0-rc7+
[ 5174.887853] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996),
BIOS 1.8.1-20150318_183358- 04/01/2014
[ 5174.888633]  ffffffff81a3b870 ffff880045393ca8 ffffffff817afaae
0000000000000000
[ 5174.889224]  ffff880045393cf8 ffff880045393ce8 ffffffff8109a846
ffff880045393cd8
[ 5174.889793]  ffffffffa02a7150 00000000000002dc 0000000000000000
ffff880045008000
[ 5174.890375] Call Trace:
[ 5174.890562]  [<ffffffff817afaae>] dump_stack+0x4c/0x65
[ 5174.890938]  [<ffffffff8109a846>] warn_slowpath_common+0x86/0xc0
[ 5174.891388]  [<ffffffff8109a8c6>] warn_slowpath_fmt+0x46/0x50
[ 5174.891808]  [<ffffffffa02a5821>] ? uio_read+0x91/0x170 [uio]
[ 5174.892237]  [<ffffffffa02a5821>] ? uio_read+0x91/0x170 [uio]
[ 5174.892653]  [<ffffffff810c584d>] __might_sleep+0x7d/0x90
[ 5174.893055]  [<ffffffff811ea023>] __might_fault+0x43/0xa0
[ 5174.893448]  [<ffffffff817b31ce>] ? schedule+0x3e/0x90
[ 5174.893820]  [<ffffffffa02a58c2>] uio_read+0x132/0x170 [uio]
[ 5174.894240]  [<ffffffff810cbb80>] ? wake_up_q+0x70/0x70
[ 5174.894620]  [<ffffffff81236168>] __vfs_read+0x28/0xe0
[ 5174.894993]  [<ffffffff81353233>] ? security_file_permission+0xa3/0xc0
[ 5174.895541]  [<ffffffff8123678f>] ? rw_verify_area+0x4f/0xf0
[ 5174.896006]  [<ffffffff812368ba>] vfs_read+0x8a/0x140
[ 5174.896391]  [<ffffffff817b28f5>] ? __schedule+0x425/0xcc0
[ 5174.896788]  [<ffffffff812375d9>] SyS_read+0x49/0xb0

The warning is a false positive because uio_read doesn't depent on
TASK_INTERRUPTIBLE after copy_to_user so it is safe to silence the
warning by an explicit setting the state to TASK_RUNNING in the path
which might call into TASK_RUNNING.

Reported-by: Andy Grover <agrover@redhat.com>
Signed-off-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-04 12:32:25 +01:00
Johannes Thumshirn e2ef939303 uio: Destroy uio_idr on module exit
Destroy uio_idr on module exit, reclaiming the allocated memory.

This was detected by the following semantic patch (written by Luis Rodriguez
<mcgrof@suse.com>)
<SmPL>
@ defines_module_init @
declarer name module_init, module_exit;
declarer name DEFINE_IDR;
identifier init;
@@

module_init(init);

@ defines_module_exit @
identifier exit;
@@

module_exit(exit);

@ declares_idr depends on defines_module_init && defines_module_exit @
identifier idr;
@@

DEFINE_IDR(idr);

@ on_exit_calls_destroy depends on declares_idr && defines_module_exit @
identifier declares_idr.idr, defines_module_exit.exit;
@@

exit(void)
{
 ...
 idr_destroy(&idr);
 ...
}

@ missing_module_idr_destroy depends on declares_idr && defines_module_exit && !on_exit_calls_destroy @
identifier declares_idr.idr, defines_module_exit.exit;
@@

exit(void)
{
 ...
 +idr_destroy(&idr);
}

</SmPL>

Signed-off-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-08-05 13:25:59 -07:00
Stephen Hemminger 9ff2c13234 uio: don't free irq that was not requested
UIO base driver should only free_irq that it has requested.
UIO supports drivers without interrupts (irq == 0) or custom handlers.

This fixes warnings like:

WARNING: CPU: 1 PID: 5478 at kernel/irq/manage.c:1244 __free_irq+0xa9/0x1e0()
Trying to free already-free IRQ 0

Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-05-24 11:55:15 -07:00
Brian Russell a087146c72 uio: Request/free irq separate from dev lifecycle
Separate irq request/free from the device lifecycle.
After device unregister the parent module can call pci_disable_msi.
>From the PCI MSI how to:

"Before calling this function, a device driver must always call free_irq()
on any interrupt for which it previously called request_irq().
Failure to do so results in a BUG_ON(), leaving the device with
MSI enabled and thus leaking its vector."

So we need to separately free the irq at unregister to allow the device
to be kept around in the case of it still having open FDs.

Signed-off-by: Brian Russell <brussell@brocade.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-03-20 13:18:16 +01:00
Cristian Stoica e0f1147cc9 uio: support memory sizes larger than 32 bits
This is a completion to 27a90700a4
The size field is also increased to allow values larger than 32 bits
on platforms that have more than 32 bit physical addresses.

Signed-off-by: Cristian Stoica <cristian.stoica@freescale.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-11-07 10:09:07 -08:00
Andy Grover f14bb039a4 uio: Export definition of struct uio_device
In order to prevent a O(n) search of the filesystem to link up its uio
node with its target configuration, TCMU needs to know the minor number
that UIO assigned. Expose the definition of this struct so TCMU can
access this field.

Signed-off-by: Andy Grover <agrover@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2014-10-02 21:35:54 -07:00
Greg Kroah-Hartman b29f680c4f Revert "uio: fix vma io range check in mmap"
This reverts commit ddb09754e6.

Linus objected to this originally, I can see why it might be needed, but
given that no one spoke up defending this patch, I'm going to revert it.

If you have hardware that requires this change, please speak up in the
future and defend the patch.

Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Bin Wang <binw@marvell.com>
Cc: Nobuhiro Iwamatsu <nobuhiro.iwamatsu.yj@renesas.com>
Cc: Norbert Ciosek <norbertciosek@gmail.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-06-17 16:07:08 -07:00
Bin Wang ddb09754e6 uio: fix vma io range check in mmap
the vma range size is always page size aligned in mmap, while the
real io space range may not be page aligned, thus leading to range
check failure in the uio_mmap_physical().

for example, in a case of io range size "mem->size == 1KB", and we
have (vma->vm_end - vma->vm_start) == 4KB, due to "len" is aligned
to page size in do_mmap_pgoff().

now fix this issue by align mem->size to page size in the check.

Signed-off-by: Bin Wang <binw@marvell.com>
Signed-off-by: Nobuhiro Iwamatsu <nobuhiro.iwamatsu.yj@renesas.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-05-27 14:11:06 -07:00
Aaro Koskinen 632fefaf1f uio: fix devm_request_irq usage
Commit e6789cd3df (uio: Simplify uio error
path by using devres functions) converted uio to use devm_request_irq().
This introduced a change in behaviour since the IRQ is associated with
the parent device instead of the created UIO device. The IRQ will remain
active after uio_unregister_device() is called, and some drivers will
crash because of this. The patch fixes this.

Signed-off-by: Aaro Koskinen <aaro.koskinen@nsn.com>
Cc: stable <stable@vger.kernel.org> # 3.13
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-12-20 08:49:17 -08:00
Linus Torvalds b655028795 uio: we cannot mmap unaligned page contents
In commit 7314e613d5 ("Fix a few incorrectly checked
[io_]remap_pfn_range() calls") the uio driver started more properly
checking the passed-in user mapping arguments against the size of the
actual uio driver data.

That in turn exposed that some driver authors apparently didn't realize
that mmap can only work on a page granularity, and had tried to use it
with smaller mappings, with the new size check catching that out.

So since it's not just the user mmap() arguments that can be confused,
make the uio mmap code also verify that the uio driver has the memory
allocated at page boundaries in order for mmap to work.  If the device
memory isn't properly aligned, we return

  [ENODEV]
    The fildes argument refers to a file whose type is not supported by mmap().

as per the open group documentation on mmap.

Reported-by: Holger Brunck <holger.brunck@keymile.com>
Acked-by: Greg KH <gregkh@linuxfoundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-12-02 11:50:37 -08:00
Linus Torvalds 1071ec7bc2 Char/Misc patches for 3.13-rc1
Here's the big char/misc driver patchset for 3.13-rc1.
 
 Lots of stuff in here, including some new drivers for Intel's "MIC"
 co-processor devices, and a new eeprom driver.  Other things include the
 driver attribute cleanups, extcon driver updates, hyperv updates, and a
 raft of other miscellaneous driver fixes.
 
 All of these have been in linux-next for a while.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'char-misc-3.13-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc

Pull char/misc patches from Greg KH:
 "Here's the big char/misc driver patchset for 3.13-rc1.

  Lots of stuff in here, including some new drivers for Intel's "MIC"
  co-processor devices, and a new eeprom driver.  Other things include
  the driver attribute cleanups, extcon driver updates, hyperv updates,
  and a raft of other miscellaneous driver fixes.

  All of these have been in linux-next for a while"

* tag 'char-misc-3.13-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (121 commits)
  misc: mic: Fixes for randconfig build errors and warnings.
  tifm: fix error return code in tifm_7xx1_probe()
  w1-gpio: Use devm_* functions
  w1-gpio: Detect of_gpio_error for first gpio
  uio: Pass pointers to virt_to_page(), not integers
  uio: fix memory leak
  misc/at24: avoid infinite loop on write()
  misc/93xx46: avoid infinite loop on write()
  misc: atmel_pwm: add deferred-probing support
  mei: wd: host_init propagate error codes from called functions
  mei: replace stray pr_debug with dev_dbg
  mei: bus: propagate error code returned by mei_me_cl_by_id
  mei: mei_cl_link remove duplicated check for open_handle_count
  mei: print correct device state during unexpected reset
  mei: nfc: fix memory leak in error path
  lkdtm: add tests for additional page permissions
  lkdtm: adjust recursion size to avoid warnings
  lkdtm: isolate stack corruption test
  mei: move host_clients_map cleanup to device init
  mei: me: downgrade two errors to debug level
  ...
2013-11-07 09:41:06 +09:00
Ben Hutchings e6418fcc8a uio: Pass pointers to virt_to_page(), not integers
Most architectures define virt_to_page() as a macro that casts its
argument such that an argument of type unsigned long will be accepted
without complaint.  However, the proper type is void *, and passing
unsigned long results in a warning on MIPS.

Compile-tested only.

Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-10-29 16:51:57 -07:00
Cong Ding 75f0aef622 uio: fix memory leak
we have to call kobject_put() to clean up the kobject after function
kobject_init(), kobject_add(), or kobject_uevent() is called.

Signed-off-by: Cong Ding <dinggnu@gmail.com>
Acked-by: Sebastian Andrzej Siewior <sebastian@breakpoint.cc>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-10-29 16:36:54 -07:00
Linus Torvalds 7314e613d5 Fix a few incorrectly checked [io_]remap_pfn_range() calls
Nico Golde reports a few straggling uses of [io_]remap_pfn_range() that
really should use the vm_iomap_memory() helper.  This trivially converts
two of them to the helper, and comments about why the third one really
needs to continue to use remap_pfn_range(), and adds the missing size
check.

Reported-by: Nico Golde <nico@ngolde.de>
Cc: stable@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org.
2013-10-29 10:21:34 -07:00
Michal Simek e6789cd3df uio: Simplify uio error path by using devres functions
Using devres functions simplify driver error path.
- Use devm_kzalloc
- Use devm_request_irq

Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Reviewed-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-09-26 08:46:45 -07:00
Linus Torvalds 542a086ac7 Driver core patches for 3.12-rc1
Here's the big driver core pull request for 3.12-rc1.
 
 Lots of tiny changes here fixing up the way sysfs attributes are
 created, to try to make drivers simpler, and fix a whole class race
 conditions with creations of device attributes after the device was
 announced to userspace.
 
 All the various pieces are acked by the different subsystem maintainers.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'driver-core-3.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

Pull driver core patches from Greg KH:
 "Here's the big driver core pull request for 3.12-rc1.

  Lots of tiny changes here fixing up the way sysfs attributes are
  created, to try to make drivers simpler, and fix a whole class race
  conditions with creations of device attributes after the device was
  announced to userspace.

  All the various pieces are acked by the different subsystem
  maintainers"

* tag 'driver-core-3.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (119 commits)
  firmware loader: fix pending_fw_head list corruption
  drivers/base/memory.c: introduce help macro to_memory_block
  dynamic debug: line queries failing due to uninitialized local variable
  sysfs: sysfs_create_groups returns a value.
  debugfs: provide debugfs_create_x64() when disabled
  rbd: convert bus code to use bus_groups
  firmware: dcdbas: use binary attribute groups
  sysfs: add sysfs_create/remove_groups for when SYSFS is not enabled
  driver core: add #include <linux/sysfs.h> to core files.
  HID: convert bus code to use dev_groups
  Input: serio: convert bus code to use drv_groups
  Input: gameport: convert bus code to use drv_groups
  driver core: firmware: use __ATTR_RW()
  driver core: core: use DEVICE_ATTR_RO
  driver core: bus: use DRIVER_ATTR_WO()
  driver core: create write-only attribute macros for devices and drivers
  sysfs: create __ATTR_WO()
  driver-core: platform: convert bus code to use dev_groups
  workqueue: convert bus code to use dev_groups
  MEI: convert bus code to use dev_groups
  ...
2013-09-03 11:37:15 -07:00
Uwe Kleine-König b65c4014ef uio: drop unused vma_count member in uio_device struct
vma_count is used write-only and so fails to be useful. So remove it.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-08-12 15:46:51 -07:00
Uwe Kleine-König 7294151d05 uio: provide vm access to UIO_MEM_PHYS maps
This makes it possible to let gdb access mappings of the process that is
being debugged.

uio_mmap_logical was moved and uio_vm_ops renamed to group related code
and differentiate to new stuff.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-08-12 15:46:51 -07:00
Greg Kroah-Hartman c9dce927e9 UIO: convert class code to use dev_groups
The dev_attrs field of struct class is going away soon, dev_groups
should be used instead.  This converts the uio class code to use the
correct field.

Cc: Hans J. Koch <hjk@hansjkoch.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-07-24 15:39:05 -07:00
Libin 52c2dad914 uio: use vma_pages() to replace (vm_end - vm_start) >> PAGE_SHIFT
(*->vm_end - *->vm_start) >> PAGE_SHIFT operation is implemented
as a inline funcion vma_pages() in linux/mm.h, so using it.

Signed-off-by: Libin <huawei.libin@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-07-03 16:07:26 -07:00
Damian Hobson-Garcia 5ed0505c71 drivers: uio: Fix UIO device registration failure
Until recently uio_get_minor() returned 0 for success and
a negative value on failure.  This became non-negative for suceess and
negative for failure.  Restore the original return value spec so that we can
successfully initialize UIO devices with a non-zero minor device
number.

Cc: "Hans J. Koch" <hjk@hansjkoch.de>
Signed-off-by: Damian Hobson-Garcia <dhobsong@igel.co.jp>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-03-29 09:08:22 -07:00
Tejun Heo 6d77093129 uio: convert to idr_alloc()
Convert to the much saner new idr interface.

Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: "Hans J. Koch" <hjk@hansjkoch.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-02-27 19:10:19 -08:00
Konstantin Khlebnikov 314e51b985 mm: kill vma flag VM_RESERVED and mm->reserved_vm counter
A long time ago, in v2.4, VM_RESERVED kept swapout process off VMA,
currently it lost original meaning but still has some effects:

 | effect                 | alternative flags
-+------------------------+---------------------------------------------
1| account as reserved_vm | VM_IO
2| skip in core dump      | VM_IO, VM_DONTDUMP
3| do not merge or expand | VM_IO, VM_DONTEXPAND, VM_HUGETLB, VM_PFNMAP
4| do not mlock           | VM_IO, VM_DONTEXPAND, VM_HUGETLB, VM_PFNMAP

This patch removes reserved_vm counter from mm_struct.  Seems like nobody
cares about it, it does not exported into userspace directly, it only
reduces total_vm showed in proc.

Thus VM_RESERVED can be replaced with VM_IO or pair VM_DONTEXPAND | VM_DONTDUMP.

remap_pfn_range() and io_remap_pfn_range() set VM_IO|VM_DONTEXPAND|VM_DONTDUMP.
remap_vmalloc_range() set VM_DONTEXPAND | VM_DONTDUMP.

[akpm@linux-foundation.org: drivers/vfio/pci/vfio_pci.c fixup]
Signed-off-by: Konstantin Khlebnikov <khlebnikov@openvz.org>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Carsten Otte <cotte@de.ibm.com>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Eric Paris <eparis@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Morris <james.l.morris@oracle.com>
Cc: Jason Baron <jbaron@redhat.com>
Cc: Kentaro Takeda <takedakn@nttdata.co.jp>
Cc: Matt Helsley <matthltc@us.ibm.com>
Cc: Nick Piggin <npiggin@kernel.dk>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Robert Richter <robert.richter@amd.com>
Cc: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: Venkatesh Pallipadi <venki@google.com>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-10-09 16:22:19 +09:00
Kai Jiang 27a90700a4 uio: Support physical addresses >32 bits on 32-bit systems
To support >32-bit physical addresses for UIO_MEM_PHYS type we need to
extend the width of 'addr' in struct uio_mem.  Numerous platforms like
embedded PPC, ARM, and X86 have support for systems with larger physical
address than logical.

Since 'addr' may contain a physical, logical, or virtual address the
easiest solution is to just change the type to 'phys_addr_t' which
should always be greater than or equal to the sizeof(void *) such that
it can properly hold any of the address types.

For physical address we can support up to a 44-bit physical address on a
typical 32-bit system as we utilize remap_pfn_range() for the mapping of
the memory region and pfn's are represnted by shifting the address by
the page size (typically 4k).

Signed-off-by: Kai Jiang <Kai.Jiang@freescale.com>
Signed-off-by: Minghuan Lian <Minghuan.Lian@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Hans J. Koch <hjk@hansjkoch.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-10-18 11:18:57 -07:00
Wanlong Gao d80df1cea0 drivers:uio:change the goto label to consistent with others
Remove one *goto* label in uio.c.

Signed-off-by: Wanlong Gao <gaowanlong@cn.fujitsu.com>
Signed-off-by: "Hans J. Koch" <hjk@hansjkoch.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-08-22 17:52:00 -07:00
Hillf Danton c6edc42fe1 uio: fix allocating minor id for uio device
The number of uio devices that could be used should be less than
UIO_MAX_DEVICES by design, and this work guards any cases in which id
more than UIO_MAX_DEVICES is utilized.

Signed-off-by: Hillf Danton <dhillf@gmail.com>
Signed-off-by: Hans J. Koch <hjk@hansjkoch.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-04-19 16:56:03 -07:00