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2017-09-10Revert "firmware: add sanity check on shutdown/suspend"Linus Torvalds1-99/+0
This reverts commit 81f95076281fdd3bc382e004ba1bce8e82fccbce. It causes random failures of firmware loading at resume time (well, random for me, it seems to be more reliable for others) because the firmware disabling is not actually synchronous with any particular resume event, and at least the btusb driver that uses a workqueue to load the firmware at resume seems to occasionally hit the "firmware loading is disabled" logic because the firmware loader hasn't gotten the resume event yet. Some kind of sanity check for not trying to load firmware when it's not possible might be a good thing, but this commit was not it. Greg seems to have silently suffered the same issue, and pointed to the likely culprit, and Gabriel C verified the revert fixed it for him too. Reported-by: Linus Torvalds <torvalds@linux-foundation.org> Pointed-at-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Tested-by: Gabriel C <nix.or.die@gmail.com> Cc: Luis R. Rodriguez <mcgrof@kernel.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-08-14Merge 4.13-rc5 into driver-core-nextGreg Kroah-Hartman1-15/+34
We want the fixes in here as well for testing. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-08-10firmware: enable a debug print for batched requestsLuis R. Rodriguez1-0/+2
Otherwise there is no easy way this actually happened. Signed-off-by: Luis R. Rodriguez <mcgrof@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-08-10firmware: define pr_fmtLuis R. Rodriguez1-0/+2
For some reason we have always forgotten this. Without this we don't get a nice prefix on our pr_debug() / pr_*() messages. Signed-off-by: Luis R. Rodriguez <mcgrof@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-08-10firmware: send -EINTR on signal abort on fallback mechanismLuis R. Rodriguez1-3/+6
Right now we send -EAGAIN to a syfs write which got interrupted. Userspace can't tell what happened though, send -EINTR if we were killed due to a signal so userspace can tell things apart. This is only applicable to the fallback mechanism. Reported-by: Martin Fuzzey <mfuzzey@parkeon.com> Signed-off-by: Luis R. Rodriguez <mcgrof@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-08-10firmware: avoid invalid fallback aborts by using killable waitLuis R. Rodriguez1-2/+1
Commit 0cb64249ca500 ("firmware_loader: abort request if wait_for_completion is interrupted") added via 4.0 added support to abort the fallback mechanism when a signal was detected and wait_for_completion_interruptible() returned -ERESTARTSYS -- for instance when a user hits CTRL-C. The abort was overly *too* effective. When a child process terminates (successful or not) the signal SIGCHLD can be sent to the parent process which ran the child in the background and later triggered a sync request for firmware through a sysfs interface which relies on the fallback mechanism. This signal in turn can be recieved by the interruptible wait we constructed on firmware_class and detects it as an abort *before* userspace could get a chance to write the firmware. Upon failure -EAGAIN is returned, so userspace is also kept in the dark about exactly what happened. We can reproduce the issue with the fw_fallback.sh selftest: Before this patch: $ sudo tools/testing/selftests/firmware/fw_fallback.sh ... tools/testing/selftests/firmware/fw_fallback.sh: error - sync firmware request cancelled due to SIGCHLD After this patch: $ sudo tools/testing/selftests/firmware/fw_fallback.sh ... tools/testing/selftests/firmware/fw_fallback.sh: SIGCHLD on sync ignored as expected Fix this by making the wait killable -- only killable by SIGKILL (kill -9). We loose the ability to allow userspace to cancel a write with CTRL-C (SIGINT), however its been decided the compromise to require SIGKILL is worth the gains. Chances of this issue occuring are low due to the number of drivers upstream exclusively relying on the fallback mechanism for firmware (2 drivers), however this is observed in the field with custom drivers with sysfs triggers to load firmware. Only distributions relying on the fallback mechanism are impacted as well. An example reported issue was on Android, as follows: 1) Android init (pid=1) fork()s (say pid=42) [this child process is totally unrelated to firmware loading, it could be sleep 2; for all we care ] 2) Android init (pid=1) does a write() on a (driver custom) sysfs file which ends up calling request_firmware() kernel side 3) The firmware loading fallback mechanism is used, the request is sent to userspace and pid 1 waits in the kernel on wait_* 4) before firmware loading completes pid 42 dies (for any reason, even normal termination) 5) Kernel delivers SIGCHLD to pid=1 to tell it a child has died, which causes -ERESTARTSYS to be returned from wait_* 6) The kernel's wait aborts and return -EAGAIN for the request_firmware() caller. Cc: stable <stable@vger.kernel.org> # 4.0 Fixes: 0cb64249ca500 ("firmware_loader: abort request if wait_for_completion is interrupted") Suggested-by: "Eric W. Biederman" <ebiederm@xmission.com> Suggested-by: Dmitry Torokhov <dmitry.torokhov@gmail.com> Tested-by: Martin Fuzzey <mfuzzey@parkeon.com> Reported-by: Martin Fuzzey <mfuzzey@parkeon.com> Signed-off-by: Luis R. Rodriguez <mcgrof@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-08-10firmware: fix batched requests - send wake up on failure on direct lookupsLuis R. Rodriguez1-8/+30
Fix batched requests from waiting forever on failure. The firmware API batched requests feature has been broken since the API call request_firmware_direct() was introduced on commit bba3a87e982ad ("firmware: Introduce request_firmware_direct()"), added on v3.14 *iff* the firmware being requested was not present in *certain kernel builds* [0]. When no firmware is found the worker which goes on to finish never informs waiters queued up of this, so any batched request will stall in what seems to be forever (MAX_SCHEDULE_TIMEOUT). Sadly, a reboot will also stall, as the reboot notifier was only designed to kill custom fallback workers. The issue seems to the user as a type of soft lockup, what *actually* happens underneath the hood is a wait call which never completes as we failed to issue a completion on error. For device drivers with optional firmware schemes (ie, Intel iwlwifi, or Netronome -- even though it uses request_firmware() and not request_firmware_direct()), this could mean that when you boot a system with multiple cards the firmware will seem to never load on the system, or that the card is just not responsive even the driver initialization. Due to differences in scheduling possible this should not always trigger -- one would need to to ensure that multiple requests are in place at the right time for this to work, also release_firmware() must not be called prior to any other incoming request. The complexity may not be worth supporting batched requests in the future given the wait mechanism is only used also for the fallback mechanism. We'll keep it for now and just fix it. Its reported that at least with the Intel WiFi cards on one system this issue was creeping up 50% of the boots [0]. Before this commit batched requests testing revealed: ============================================================================ CONFIG_FW_LOADER_USER_HELPER_FALLBACK=n CONFIG_FW_LOADER_USER_HELPER=y Most common Linux distribution setup. API-type no-firmware-found firmware-found ---------------------------------------------------------------------- request_firmware() FAIL OK request_firmware_direct() FAIL OK request_firmware_nowait(uevent=true) FAIL OK request_firmware_nowait(uevent=false) FAIL OK ============================================================================ CONFIG_FW_LOADER_USER_HELPER_FALLBACK=n CONFIG_FW_LOADER_USER_HELPER=n Only possible if CONFIG_DELL_RBU=n and CONFIG_LEDS_LP55XX_COMMON=n, rare. API-type no-firmware-found firmware-found ---------------------------------------------------------------------- request_firmware() FAIL OK request_firmware_direct() FAIL OK request_firmware_nowait(uevent=true) FAIL OK request_firmware_nowait(uevent=false) FAIL OK ============================================================================ CONFIG_FW_LOADER_USER_HELPER_FALLBACK=y CONFIG_FW_LOADER_USER_HELPER=y Google Android setup. API-type no-firmware-found firmware-found ---------------------------------------------------------------------- request_firmware() OK OK request_firmware_direct() FAIL OK request_firmware_nowait(uevent=true) OK OK request_firmware_nowait(uevent=false) OK OK ============================================================================ Ater this commit batched testing results: ============================================================================ CONFIG_FW_LOADER_USER_HELPER_FALLBACK=n CONFIG_FW_LOADER_USER_HELPER=y Most common Linux distribution setup. API-type no-firmware-found firmware-found ---------------------------------------------------------------------- request_firmware() OK OK request_firmware_direct() OK OK request_firmware_nowait(uevent=true) OK OK request_firmware_nowait(uevent=false) OK OK ============================================================================ CONFIG_FW_LOADER_USER_HELPER_FALLBACK=n CONFIG_FW_LOADER_USER_HELPER=n Only possible if CONFIG_DELL_RBU=n and CONFIG_LEDS_LP55XX_COMMON=n, rare. API-type no-firmware-found firmware-found ---------------------------------------------------------------------- request_firmware() OK OK request_firmware_direct() OK OK request_firmware_nowait(uevent=true) OK OK request_firmware_nowait(uevent=false) OK OK ============================================================================ CONFIG_FW_LOADER_USER_HELPER_FALLBACK=y CONFIG_FW_LOADER_USER_HELPER=y Google Android setup. API-type no-firmware-found firmware-found ---------------------------------------------------------------------- request_firmware() OK OK request_firmware_direct() OK OK request_firmware_nowait(uevent=true) OK OK request_firmware_nowait(uevent=false) OK OK ============================================================================ [0] https://bugzilla.kernel.org/show_bug.cgi?id=195477 Cc: stable <stable@vger.kernel.org> # v3.14 Fixes: bba3a87e982ad ("firmware: Introduce request_firmware_direct()" Reported-by: Nicolas <nbroeking@me.com> Reported-by: John Ewalt <jewalt@lgsinnovations.com> Reported-by: Jakub Kicinski <jakub.kicinski@netronome.com> Signed-off-by: Luis R. Rodriguez <mcgrof@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-08-10firmware: fix batched requests - wake all waitersLuis R. Rodriguez1-7/+5
The firmware cache mechanism serves two purposes, the secondary purpose is not well documented nor understood. This fixes a regression with the secondary purpose of the firmware cache mechanism: batched requests on successful lookups. Without this fix *any* time a batched request is triggered, secondary requests for which the batched request mechanism was designed for will seem to last forver and seem to never return. This issue is present for all kernel builds possible, and a hard reset is required. The firmware cache is used for: 1) Addressing races with file lookups during the suspend/resume cycle by keeping firmware in memory during the suspend/resume cycle 2) Batched requests for the same file rely only on work from the first file lookup, which keeps the firmware in memory until the last release_firmware() is called Batched requests *only* take effect if secondary requests come in prior to the first user calling release_firmware(). The devres name used for the internal firmware cache is used as a hint other pending requests are ongoing, the firmware buffer data is kept in memory until the last user of the buffer calls release_firmware(), therefore serializing requests and delaying the release until all requests are done. Batched requests wait for a wakup or signal so we can rely on the first file fetch to write to the pending secondary requests. Commit 5b029624948d ("firmware: do not use fw_lock for fw_state protection") ported the firmware API to use swait, and in doing so failed to convert complete_all() to swake_up_all() -- it used swake_up(), loosing the ability for *some* batched requests to take effect. We *could* fix this by just using swake_up_all() *but* swait is now known to be very special use case, so its best to just move away from it. So we just go back to using completions as before commit 5b029624948d ("firmware: do not use fw_lock for fw_state protection") given this was using complete_all(). Without this fix it has been reported plugging in two Intel 6260 Wifi cards on a system will end up enumerating the two devices only 50% of the time [0]. The ported swake_up() should have actually handled the case with two devices, however, *if more than two cards are used* the swake_up() would not have sufficed. This change is only part of the required fixes for batched requests. Another fix is provided in the next patch. This particular change should fix the cases where more than three requests with the same firmware name is used, otherwise batched requests will wait for MAX_SCHEDULE_TIMEOUT and just timeout eventually. Below is a summary of tests triggering batched requests on different kernel builds. Before this patch: ============================================================================ CONFIG_FW_LOADER_USER_HELPER_FALLBACK=n CONFIG_FW_LOADER_USER_HELPER=y Most common Linux distribution setup. API-type no-firmware-found firmware-found ---------------------------------------------------------------------- request_firmware() FAIL FAIL request_firmware_direct() FAIL FAIL request_firmware_nowait(uevent=true) FAIL FAIL request_firmware_nowait(uevent=false) FAIL FAIL ============================================================================ CONFIG_FW_LOADER_USER_HELPER_FALLBACK=n CONFIG_FW_LOADER_USER_HELPER=n Only possible if CONFIG_DELL_RBU=n and CONFIG_LEDS_LP55XX_COMMON=n, rare. API-type no-firmware-found firmware-found ---------------------------------------------------------------------- request_firmware() FAIL FAIL request_firmware_direct() FAIL FAIL request_firmware_nowait(uevent=true) FAIL FAIL request_firmware_nowait(uevent=false) FAIL FAIL ============================================================================ CONFIG_FW_LOADER_USER_HELPER_FALLBACK=y CONFIG_FW_LOADER_USER_HELPER=y Google Android setup. API-type no-firmware-found firmware-found ---------------------------------------------------------------------- request_firmware() FAIL FAIL request_firmware_direct() FAIL FAIL request_firmware_nowait(uevent=true) FAIL FAIL request_firmware_nowait(uevent=false) FAIL FAIL ============================================================================ After this patch: ============================================================================ CONFIG_FW_LOADER_USER_HELPER_FALLBACK=n CONFIG_FW_LOADER_USER_HELPER=y Most common Linux distribution setup. API-type no-firmware-found firmware-found ---------------------------------------------------------------------- request_firmware() FAIL OK request_firmware_direct() FAIL OK request_firmware_nowait(uevent=true) FAIL OK request_firmware_nowait(uevent=false) FAIL OK ============================================================================ CONFIG_FW_LOADER_USER_HELPER_FALLBACK=n CONFIG_FW_LOADER_USER_HELPER=n Only possible if CONFIG_DELL_RBU=n and CONFIG_LEDS_LP55XX_COMMON=n, rare. API-type no-firmware-found firmware-found ---------------------------------------------------------------------- request_firmware() FAIL OK request_firmware_direct() FAIL OK request_firmware_nowait(uevent=true) FAIL OK request_firmware_nowait(uevent=false) FAIL OK ============================================================================ CONFIG_FW_LOADER_USER_HELPER_FALLBACK=y CONFIG_FW_LOADER_USER_HELPER=y Google Android setup. API-type no-firmware-found firmware-found ---------------------------------------------------------------------- request_firmware() OK OK request_firmware_direct() FAIL OK request_firmware_nowait(uevent=true) OK OK request_firmware_nowait(uevent=false) OK OK ============================================================================ [0] https://bugzilla.kernel.org/show_bug.cgi?id=195477 CC: <stable@vger.kernel.org> [4.10+] Cc: Ming Lei <ming.lei@redhat.com> Fixes: 5b029624948d ("firmware: do not use fw_lock for fw_state protection") Reported-by: Jakub Kicinski <jakub.kicinski@netronome.com> Signed-off-by: Luis R. Rodriguez <mcgrof@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-03firmware: move umh try locks into the umh codeLuis R. Rodriguez1-32/+36
This moves the usermode helper locks into only code paths that use the usermode helper API from the kernel. The usermode helper locks were originally added to prevent stalling suspend, later the firmware cache was added to help with this, and further later direct filesystem lookup was added by Linus to completely bypass udev due to the amount of issues the umh approach had. The usermode helper locks were kept even when the direct filesystem lookup mechanism is used though. A lot has changed since the original usermode helper locks were added but the recent commit which added the code for firmware_enabled() are intended to address any possible races cured only as collateral by using the locks as though side consequence of code evolution and this not being addressed any time sooner. With the firmware_enabled() code in place we are a bit more sure to move the usermode helper locks to UMH only code. There is a bit of history here so let's recap a bit of it to ensure nothing is lost and things are clear. The direct filesystem approach to loading firmware is rather new, it was added via commit abb139e75c2cdb ("firmware: teach the kernel to load firmware files directly from the filesystem") by Linus merged on the v3.7 release, to enable to bypass udev. usermodehelper_read_lock_wait() was added earlier via commit 9b78c1da60b3c ("firmware_class: Do not warn that system is not ready from async loads") merged on v3.4, after Rafael noted that the async firmware API call request_firmware_nowait() should not be penalized to fail if userspace is not available yet or frozen, it'd allow for a timeout grace period before giving up. The WARN_ON() was kept for the sync firmware API call though on request_firmware(). At this time there was no direct filesystem lookup for firmware though. The original usermode helper lock came from commit a144c6a6c924a ("PM: Print a warning if firmware is requested when tasks are frozen") merged on the v3.0 kernel by Rafael to print a warning back when firmware requests were used on resume(), thaw() or restore() callbacks and there was no direct fs lookups or the firmware cache. Signed-off-by: Luis R. Rodriguez <mcgrof@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-03firmware: move assign_firmware_buf() further upLuis R. Rodriguez1-39/+38
This will make subsequent changes easier to read. Signed-off-by: Luis R. Rodriguez <mcgrof@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-03firmware: add sanity check on shutdown/suspendLuis R. Rodriguez1-0/+99
The firmware API should not be used after we go to suspend and after we reboot/halt. The suspend/resume case is a bit complex, so this documents that so things are clearer. We want to know about users of the API in incorrect places so that their callers are corrected, so this also adds a warn for those cases. Signed-off-by: Luis R. Rodriguez <mcgrof@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-03firmware: always enable the reboot notifierLuis R. Rodriguez1-19/+18
Now that we've have proper wrappers for the fallback mechanism we can easily share the reboot notifier for the firmware_class at all times. This change will make subsequent modifications to the reboot notifier easier to review. Signed-off-by: Luis R. Rodriguez <mcgrof@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-03firmware: share fw fallback killing on reboot/suspendLuis R. Rodriguez1-15/+14
We kill pending fallback requests on suspend and reboot, the only difference is that on suspend we only kill custom fallback requests. Provide a wrapper that lets us customize the request with a flag. This also lets us simplify the #ifdef'ery over the calls. Signed-off-by: Luis R. Rodriguez <mcgrof@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-03firmware: move kill_requests_without_uevent() up aboveLuis R. Rodriguez1-16/+16
This routine will used in functions declared earlier next. This code shift has no functional changes, it will make subsequent changes easier to read. Signed-off-by: Luis R. Rodriguez <mcgrof@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-27firmware: fix NULL pointer dereference in __fw_load_abort()Luis R. Rodriguez1-4/+1
Since commit 5d47ec02c37ea6 ("firmware: Correct handling of fw_state_wait() return value") fw_load_abort() could be called twice and lead us to a kernel crash. This happens only when the firmware fallback mechanism (regular or custom) is used. The fallback mechanism exposes a sysfs interface for userspace to upload a file and notify the kernel when the file is loaded and ready, or to cancel an upload by echo'ing -1 into on the loading file: echo -n "-1" > /sys/$DEVPATH/loading This will call fw_load_abort(). Some distributions actually have a udev rule in place to *always* immediately cancel all firmware fallback mechanism requests (Debian), they have: $ cat /lib/udev/rules.d/50-firmware.rules # stub for immediately telling the kernel that userspace firmware loading # failed; necessary to avoid long timeouts with CONFIG_FW_LOADER_USER_HELPER=y SUBSYSTEM=="firmware", ACTION=="add", ATTR{loading}="-1 Distributions with this udev rule would run into this crash only if the fallback mechanism is used. Since most distributions disable by default using the fallback mechanism (CONFIG_FW_LOADER_USER_HELPER_FALLBACK), this would typicaly mean only 2 drivers which *require* the fallback mechanism could typically incur a crash: drivers/firmware/dell_rbu.c and the drivers/leds/leds-lp55xx-common.c driver. Distributions enabling CONFIG_FW_LOADER_USER_HELPER_FALLBACK by default are obviously more exposed to this crash. The crash happens because after commit 5b029624948d ("firmware: do not use fw_lock for fw_state protection") and subsequent fix commit 5d47ec02c37ea6 ("firmware: Correct handling of fw_state_wait() return value") a race can happen between this cancelation and the firmware fw_state_wait_timeout() being woken up after a state change with which fw_load_abort() as that calls swake_up(). Upon error fw_state_wait_timeout() will also again call fw_load_abort() and trigger a null reference. At first glance we could just fix this with a !buf check on fw_load_abort() before accessing buf->fw_st, however there is a logical issue in having a state machine used for the fallback mechanism and preventing access from it once we abort as its inside the buf (buf->fw_st). The firmware_class.c code is setting the buf to NULL to annotate an abort has occurred. Replace this mechanism by simply using the state check instead. All the other code in place already uses similar checks for aborting as well so no further changes are needed. An oops can be reproduced with the new fw_fallback.sh fallback mechanism cancellation test. Either cancelling the fallback mechanism or the custom fallback mechanism triggers a crash. mcgrof@piggy ~/linux-next/tools/testing/selftests/firmware (git::20170111-fw-fixes)$ sudo ./fw_fallback.sh ./fw_fallback.sh: timeout works ./fw_fallback.sh: firmware comparison works ./fw_fallback.sh: fallback mechanism works [ this then sits here when it is trying the cancellation test ] Kernel log: test_firmware: loading 'nope-test-firmware.bin' misc test_firmware: Direct firmware load for nope-test-firmware.bin failed with error -2 misc test_firmware: Falling back to user helper BUG: unable to handle kernel NULL pointer dereference at 0000000000000038 IP: _request_firmware+0xa27/0xad0 PGD 0 Oops: 0000 [#1] SMP Modules linked in: test_firmware(E) ... etc ... CPU: 1 PID: 1396 Comm: fw_fallback.sh Tainted: G W E 4.10.0-rc3-next-20170111+ #30 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.10.1-0-g8891697-prebuilt.qemu-project.org 04/01/2014 task: ffff9740b27f4340 task.stack: ffffbb15c0bc8000 RIP: 0010:_request_firmware+0xa27/0xad0 RSP: 0018:ffffbb15c0bcbd10 EFLAGS: 00010246 RAX: 00000000fffffffe RBX: ffff9740afe5aa80 RCX: 0000000000000000 RDX: ffff9740b27f4340 RSI: 0000000000000283 RDI: 0000000000000000 RBP: ffffbb15c0bcbd90 R08: ffffbb15c0bcbcd8 R09: 0000000000000000 R10: 0000000894a0d4b1 R11: 000000000000008c R12: ffffffffc0312480 R13: 0000000000000005 R14: ffff9740b1c32400 R15: 00000000000003e8 FS: 00007f8604422700(0000) GS:ffff9740bfc80000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000038 CR3: 000000012164c000 CR4: 00000000000006e0 Call Trace: request_firmware+0x37/0x50 trigger_request_store+0x79/0xd0 [test_firmware] dev_attr_store+0x18/0x30 sysfs_kf_write+0x37/0x40 kernfs_fop_write+0x110/0x1a0 __vfs_write+0x37/0x160 ? _cond_resched+0x1a/0x50 vfs_write+0xb5/0x1a0 SyS_write+0x55/0xc0 ? trace_do_page_fault+0x37/0xd0 entry_SYSCALL_64_fastpath+0x1e/0xad RIP: 0033:0x7f8603f49620 RSP: 002b:00007fff6287b788 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 000055c307b110a0 RCX: 00007f8603f49620 RDX: 0000000000000016 RSI: 000055c3084d8a90 RDI: 0000000000000001 RBP: 0000000000000016 R08: 000000000000c0ff R09: 000055c3084d6336 R10: 000055c307b108b0 R11: 0000000000000246 R12: 000055c307b13c80 R13: 000055c3084d6320 R14: 0000000000000000 R15: 00007fff6287b950 Code: 9f 64 84 e8 9c 61 fe ff b8 f4 ff ff ff e9 6b f9 ff ff 48 c7 c7 40 6b 8d 84 89 45 a8 e8 43 84 18 00 49 8b be 00 03 00 00 8b 45 a8 <83> 7f 38 02 74 08 e8 6e ec ff ff 8b 45 a8 49 c7 86 00 03 00 00 RIP: _request_firmware+0xa27/0xad0 RSP: ffffbb15c0bcbd10 CR2: 0000000000000038 ---[ end trace 6d94ac339c133e6f ]--- Fixes: 5d47ec02c37e ("firmware: Correct handling of fw_state_wait() return value") Reported-and-Tested-by: Jakub Kicinski <jakub.kicinski@netronome.com> Reported-and-Tested-by: Patrick Bruenn <p.bruenn@beckhoff.com> Reported-by: Chris Wilson <chris@chris-wilson.co.uk> CC: <stable@vger.kernel.org> [3.10+] Signed-off-by: Luis R. Rodriguez <mcgrof@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-12-08firmware: Correct handling of fw_state_wait() return valueBjorn Andersson1-7/+6
When request_firmware() finds an already open firmware object it will wait for that object to become fully loaded and then check the status. As __fw_state_wait_common() succeeds the timeout value returned will be truncated in _request_firmware_prepare() and interpreted as -EPERM. Prior to "firmware: do not use fw_lock for fw_state protection" the code did test if we where in the "done" state before sleeping, causing this particular code path to succeed, in some cases. As the callers are interested in the result of the wait and not the remaining timeout the return value of __fw_state_wait_common() is changed to signal "done" or "error", which simplifies the logic in _request_firmware_load() as well. Fixes: 5b029624948d ("firmware: do not use fw_lock for fw_state protection") Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org> Reviewed-by: Daniel Wagner <daniel.wagner@bmw-carit.de> Acked-by: Luis R. Rodriguez <mcgrof@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-12-01firmware: remove warning at documentation generation timeSilvio Fricke1-3/+3
This patch removes following error at for `make htmldocs`. No functional change. ./drivers/base/firmware_class.c:1348: WARNING: Bullet list ends without a blank line; unexpected unindent. Signed-off-by: Silvio Fricke <silvio.fricke@gmail.com> Reviewed-by: Mauro Carvalho Chehab <mchehab@s-opensource.com> Acked-by: Luis R. Rodriguez <mcgrof@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-11-29firmware: move fw_state_is_done() into UHM sectionDaniel Wagner1-7/+7
fw_state_is_done() is only used for UHM so moved into that section. Cc: Ming Lei <ming.lei@canonical.com> Signed-off-by: Daniel Wagner <daniel.wagner@bmw-carit.de> Acked-by: Luis R. Rodriguez <mcgrof@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-11-29firmware: do not use fw_lock for fw_state protectionDaniel Wagner1-36/+15
fw_lock is to use to protect 'corner cases' inside firmware_class. It is not exactly clear what those corner cases are nor what it exactly protects. fw_state can be used without needing the fw_lock to protect its state transition and wake ups. fw_state is holds the state in status and the completion is used to wake up all waiters (in this case that is the user land helper so only one). This operation has to be 'atomic' to avoid races. We can do this by using swait which takes care we don't miss any wake up. We use also swait instead of wait because don't need all the additional features wait provides. Note there some more cleanups possible after with this change. For example for !CONFIG_FW_LOADER_USER_HELPER we don't check for the state anymore. Let's to this in the next patch instead mingling to many changes into this one. And yes you get a gcc warning "‘__fw_state_check’ defined but not used [-Wunused-function] code." for the time beeing. Cc: Ming Lei <ming.lei@canonical.com> Signed-off-by: Daniel Wagner <daniel.wagner@bmw-carit.de> Acked-by: Luis R. Rodriguez <mcgrof@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-11-29firmware: drop bit ops in favor of simple state machineDaniel Wagner1-7/+5
We track the state of the firmware loading with bit ops. Since the state machine has only a few states and they are all mutual exclusive there are only a few simple state transition we can model this simplify. UNKNOWN -> LOADING -> DONE | ABORTED Because we don't use any bit ops on fw_state::status anymore we are able to change the data type to enum fw_status and update the function arguments accordingly. READ_ONCE() and WRITE_ONCE() are propably not needed because there are a lot of load and stores around fw_st->status. But let's make it explicit and not be sorry later. Cc: Ming Lei <ming.lei@canonical.com> Signed-off-by: Daniel Wagner <daniel.wagner@bmw-carit.de> Acked-by: Luis R. Rodriguez <mcgrof@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-11-29firmware: refactor loading statusDaniel Wagner1-34/+93
The firmware loader tracks the current state of the loading process via unsigned long status and a completion in struct firmware_buf. Instead of open code tracking the state, introduce data structure which encapsulate the state tracking and synchronization. While at it also separate UHM states from direct loading states, e.g. the loading_timeout is only defined when CONFIG_FW_LOADER_USER_HELPER. Cc: Ming Lei <ming.lei@canonical.com> Signed-off-by: Daniel Wagner <daniel.wagner@bmw-carit.de> Acked-by: Luis R. Rodriguez <mcgrof@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-11-29firmware: fix usermode helper fallback loadingYves-Alexis Perez1-3/+4
When you use the firmware usermode helper fallback with a timeout value set to a value greater than INT_MAX (2147483647) a cast overflow issue causes the timeout value to go negative and breaks all usermode helper loading. This regression was introduced through commit 68ff2a00dbf5 ("firmware_loader: handle timeout via wait_for_completion_interruptible_timeout()") on kernel v4.0. The firmware_class drivers relies on the firmware usermode helper fallback as a mechanism to look for firmware if the direct filesystem search failed only if: a) You've enabled CONFIG_FW_LOADER_USER_HELPER_FALLBACK (not many distros): Then all of these callers will rely on the fallback mechanism in case the firmware is not found through an initial direct filesystem lookup: o request_firmware() o request_firmware_into_buf() o request_firmware_nowait() b) If you've only enabled CONFIG_FW_LOADER_USER_HELPER (most distros): Then only callers using request_firmware_nowait() with the second argument set to false, this explicitly is requesting the UMH firmware fallback to be relied on in case the first filesystem lookup fails. Using Coccinelle SmPL grammar we have identified only two drivers explicitly requesting the UMH firmware fallback mechanism: - drivers/firmware/dell_rbu.c - drivers/leds/leds-lp55xx-common.c Since most distributions only enable CONFIG_FW_LOADER_USER_HELPER the biggest impact of this regression are users of the dell_rbu and leds-lp55xx-common device driver which required the UMH to find their respective needed firmwares. The default timeout for the UMH is set to 60 seconds always, as of commit 68ff2a00dbf5 ("firmware_loader: handle timeout via wait_for_completion_interruptible_timeout()") the timeout was bumped to MAX_JIFFY_OFFSET ((LONG_MAX >> 1)-1). Additionally the MAX_JIFFY_OFFSET value was also used if the timeout was configured by a user to 0. The following works: echo 2147483647 > /sys/class/firmware/timeout But both of the following set the timeout to MAX_JIFFY_OFFSET even if we display 0 back to userspace: echo 2147483648 > /sys/class/firmware/timeout cat /sys/class/firmware/timeout 0 echo 0> /sys/class/firmware/timeout cat /sys/class/firmware/timeout 0 A max value of INT_MAX (2147483647) seconds is therefore implicit due to the another cast with simple_strtol(). This fixes the secondary cast (the first one is simple_strtol() but its an issue only by forcing an implicit limit) by re-using the timeout variable and only setting retval in appropriate cases. Lastly worth noting systemd had ripped out the UMH firmware fallback mechanism from udev since udev 2014 via commit be2ea723b1d023b3d ("udev: remove userspace firmware loading support"), so as of systemd v217. Signed-off-by: Yves-Alexis Perez <corsac@corsac.net> Fixes: 68ff2a00dbf5 "firmware_loader: handle timeout via wait_for_completion_interruptible_timeout()" Cc: Luis R. Rodriguez <mcgrof@kernel.org> Cc: Ming Lei <ming.lei@canonical.com> Cc: Bjorn Andersson <bjorn.andersson@linaro.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: stable@vger.kernel.org Acked-by: Luis R. Rodriguez <mcgrof@kernel.org> Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org> [mcgrof@kernel.org: gave commit log a whole lot of love] Signed-off-by: Luis R. Rodriguez <mcgrof@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-11-29driver core: firmware_class: convert to use class_groupsGreg Kroah-Hartman1-4/+6
Convert the firmware core to use class_groups instead of class_attrs as that's the correct way to handle lists of class attribute files. Cc: Ming Lei <ming.lei@canonical.com> Acked-by: Luis R. Rodriguez <mcgrof@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-08-02firmware: support loading into a pre-allocated bufferStephen Boyd1-26/+99
Some systems are memory constrained but they need to load very large firmwares. The firmware subsystem allows drivers to request this firmware be loaded from the filesystem, but this requires that the entire firmware be loaded into kernel memory first before it's provided to the driver. This can lead to a situation where we map the firmware twice, once to load the firmware into kernel memory and once to copy the firmware into the final resting place. This creates needless memory pressure and delays loading because we have to copy from kernel memory to somewhere else. Let's add a request_firmware_into_buf() API that allows drivers to request firmware be loaded directly into a pre-allocated buffer. This skips the intermediate step of allocating a buffer in kernel memory to hold the firmware image while it's read from the filesystem. It also requires that drivers know how much memory they'll require before requesting the firmware and negates any benefits of firmware caching because the firmware layer doesn't manage the buffer lifetime. For a 16MB buffer, about half the time is spent performing a memcpy from the buffer to the final resting place. I see loading times go from 0.081171 seconds to 0.047696 seconds after applying this patch. Plus the vmalloc pressure is reduced. This is based on a patch from Vikram Mulukutla on codeaurora.org: https://www.codeaurora.org/cgit/quic/la/kernel/msm-3.18/commit/drivers/base/firmware_class.c?h=rel/msm-3.18&id=0a328c5f6cd999f5c591f172216835636f39bcb5 Link: http://lkml.kernel.org/r/20160607164741.31849-4-stephen.boyd@linaro.org Signed-off-by: Stephen Boyd <stephen.boyd@linaro.org> Cc: Mimi Zohar <zohar@linux.vnet.ibm.com> Cc: Vikram Mulukutla <markivx@codeaurora.org> Cc: Mark Brown <broonie@kernel.org> Cc: Ming Lei <ming.lei@canonical.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-08-02firmware: provide infrastructure to make fw caching optionalVikram Mulukutla1-2/+5
Some low memory systems with complex peripherals cannot afford to have the relatively large firmware images taking up valuable memory during suspend and resume. Change the internal implementation of firmware_class to disallow caching based on a configurable option. In the near future, variants of request_firmware will take advantage of this feature. Link: http://lkml.kernel.org/r/20160607164741.31849-3-stephen.boyd@linaro.org [stephen.boyd@linaro.org: Drop firmware_desc design and use flags] Signed-off-by: Vikram Mulukutla <markivx@codeaurora.org> Signed-off-by: Stephen Boyd <stephen.boyd@linaro.org> Cc: Mimi Zohar <zohar@linux.vnet.ibm.com> Cc: Mark Brown <broonie@kernel.org> Cc: Ming Lei <ming.lei@canonical.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-08-02firmware: consolidate kmap/read/write logicStephen Boyd1-31/+26
Some systems are memory constrained but they need to load very large firmwares. The firmware subsystem allows drivers to request this firmware be loaded from the filesystem, but this requires that the entire firmware be loaded into kernel memory first before it's provided to the driver. This can lead to a situation where we map the firmware twice, once to load the firmware into kernel memory and once to copy the firmware into the final resting place. This design creates needless memory pressure and delays loading because we have to copy from kernel memory to somewhere else. This patch sets adds support to the request firmware API to load the firmware directly into a pre-allocated buffer, skipping the intermediate copying step and alleviating memory pressure during firmware loading. The drawback is that we can't use the firmware caching feature because the memory for the firmware cache is not managed by the firmware layer. This patch (of 3): We use similar structured code to read and write the kmapped firmware pages. The only difference is read copies from the kmap region and write copies to it. Consolidate this into one function to reduce duplication. Link: http://lkml.kernel.org/r/20160607164741.31849-2-stephen.boyd@linaro.org Signed-off-by: Stephen Boyd <stephen.boyd@linaro.org> Cc: Vikram Mulukutla <markivx@codeaurora.org> Cc: Mimi Zohar <zohar@linux.vnet.ibm.com> Cc: Mark Brown <broonie@kernel.org> Cc: Ming Lei <ming.lei@canonical.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-03-17Merge tag 'char-misc-4.6-rc1' of ↵Linus Torvalds1-5/+4
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc Pull char/misc updates from Greg KH: "Here is the big char/misc driver update for 4.6-rc1. The majority of the patches here is hwtracing and some new mic drivers, but there's a lot of other driver updates as well. Full details in the shortlog. All have been in linux-next for a while with no reported issues" * tag 'char-misc-4.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (238 commits) goldfish: Fix build error of missing ioremap on UM nvmem: mediatek: Fix later provider initialization nvmem: imx-ocotp: Fix return value of imx_ocotp_read nvmem: Fix dependencies for !HAS_IOMEM archs char: genrtc: replace blacklist with whitelist drivers/hwtracing: make coresight-etm-perf.c explicitly non-modular drivers: char: mem: fix IS_ERROR_VALUE usage char: xillybus: Fix internal data structure initialization pch_phub: return -ENODATA if ROM can't be mapped Drivers: hv: vmbus: Support kexec on ws2012 r2 and above Drivers: hv: vmbus: Support handling messages on multiple CPUs Drivers: hv: utils: Remove util transport handler from list if registration fails Drivers: hv: util: Pass the channel information during the init call Drivers: hv: vmbus: avoid unneeded compiler optimizations in vmbus_wait_for_unload() Drivers: hv: vmbus: remove code duplication in message handling Drivers: hv: vmbus: avoid wait_for_completion() on crash Drivers: hv: vmbus: don't loose HVMSG_TIMER_EXPIRED messages misc: at24: replace memory_accessor with nvmem_device_read eeprom: 93xx46: extend driver to plug into the NVMEM framework eeprom: at25: extend driver to plug into the NVMEM framework ...
2016-02-29firmware: change kernel read fail to dev_dbg()Luis R. Rodriguez1-2/+6
When we now use the new kernel_read_file_from_path() we are reporting a failure when we iterate over all the paths possible for firmware. Before using kernel_read_file_from_path() we only reported a failure once we confirmed a file existed with filp_open() but failed with fw_read_file_contents(). With kernel_read_file_from_path() both are done for us and we obviously are now reporting too much information given that some optional paths will always fail and clutter the logs. fw_get_filesystem_firmware() already has a check for failure and uses an internal flag, FW_OPT_NO_WARN, but this does not let us capture other unxpected errors. This enables that as changed by Neil via commit: "firmware: Be a bit more verbose about direct firmware loading failure" Reported-by: Heiner Kallweit <hkallweit1@gmail.com> Cc: Neil Horman <nhorman@tuxdriver.com> Cc: Heiner Kallweit <hkallweit1@gmail.com> Cc: Mimi Zohar <zohar@linux.vnet.ibm.com> Cc: Kees Cook <keescook@chromium.org> Signed-off-by: Luis R. Rodriguez <mcgrof@kernel.org> Acked-by: Kees Cook <keescook@chromium.org> Acked-by: Ming Lei <ming.lei@canonical.com> Signed-off-by: James Morris <james.l.morris@oracle.com>
2016-02-21firmware: replace call to fw_read_file_contents() with kernel versionMimi Zohar1-42/+10
Replace the fw_read_file_contents with kernel_file_read_from_path(). Although none of the upstreamed LSMs define a kernel_fw_from_file hook, IMA is called by the security function to prevent unsigned firmware from being loaded and to measure/appraise signed firmware, based on policy. Instead of reading the firmware twice, once for measuring/appraising the firmware and again for reading the firmware contents into memory, the kernel_post_read_file() security hook calculates the file hash based on the in memory file buffer. The firmware is read once. This patch removes the LSM kernel_fw_from_file() hook and security call. Changelog v4+: - revert dropped buf->size assignment - reported by Sergey Senozhatsky v3: - remove kernel_fw_from_file hook - use kernel_file_read_from_path() - requested by Luis v2: - reordered and squashed firmware patches - fix MAX firmware size (Kees Cook) Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com> Acked-by: Kees Cook <keescook@chromium.org> Acked-by: Luis R. Rodriguez <mcgrof@kernel.org>
2016-02-18firmware: clean up filesystem load exit pathKees Cook1-7/+5
This makes the error and success paths more readable while trying to load firmware from the filesystem. Signed-off-by: Kees Cook <keescook@chromium.org> Cc: Josh Boyer <jwboyer@fedoraproject.org> Cc: David Howells <dhowells@redhat.com> Acked-by: Luis R. Rodriguez <mcgrof@kernel.org> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2016-02-18firmware: move completing fw into a helperLuis R. Rodriguez1-4/+10
This will be re-used later through a new extensible interface. Reviewed-by: Josh Boyer <jwboyer@fedoraproject.org> Signed-off-by: Luis R. Rodriguez <mcgrof@kernel.org> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com> Acked-by: Kees Cook <keescook@chromium.org>
2016-02-18firmware: simplify dev_*() print messages for generic helpersLuis R. Rodriguez1-4/+4
Simplify a few of the *generic* shared dev_warn() and dev_dbg() print messages for three reasons: 0) Historically firmware_class code was added to help get device driver firmware binaries but these days request_firmware*() helpers are being repurposed for general *system data* needed by the kernel. 1) This will also help generalize shared code as much as possible later in the future in consideration for a new extensible firmware API which will enable to separate usermode helper code out as much as possible. 2) Kees Cook pointed out the the prints already have the device associated as dev_*() helpers are used, that should help identify the user and case in which the helpers are used. That should provide enough context and simplifies the messages further. v4: generalize debug/warn messages even further as suggested by Kees Cook. Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: David Howells <dhowells@redhat.com> Cc: Kees Cook <keescook@chromium.org> Cc: Casey Schaufler <casey@schaufler-ca.com> Cc: Ming Lei <ming.lei@canonical.com> Cc: Takashi Iwai <tiwai@suse.de> Cc: Vojtěch Pavlík <vojtech@suse.cz> Cc: Kyle McMartin <kyle@kernel.org> Cc: Matthew Garrett <mjg59@srcf.ucam.org> Cc: linux-kernel@vger.kernel.org Signed-off-by: Luis R. Rodriguez <mcgrof@kernel.org> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com> Acked-by: Kees Cook <keescook@chromium.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-02-08firmware: Change the page arrary alloc to vmallocChen Feng1-5/+4
No need to use use continuous memory, it may be fail when memory deeply fragmented. Signed-off-by: Chen Feng <puck.chen@hisilicon.com> Signed-off-by: Xia Qing <saberlily.xia@hisilicon.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-02-08firmware: simplify dev_*() print messages for generic helpersLuis R. Rodriguez1-4/+4
Simplify a few of the *generic* shared dev_warn() and dev_dbg() print messages for three reasons: 0) Historically firmware_class code was added to help get device driver firmware binaries but these days request_firmware*() helpers are being repurposed for general *system data* needed by the kernel. 1) This will also help generalize shared code as much as possible later in the future in consideration for a new extensible firmware API which will enable to separate usermode helper code out as much as possible. 2) Kees Cook pointed out the the prints already have the device associated as dev_*() helpers are used, that should help identify the user and case in which the helpers are used. That should provide enough context and simplifies the messages further. v4: generalize debug/warn messages even further as suggested by Kees Cook. Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: David Howells <dhowells@redhat.com> Cc: Casey Schaufler <casey@schaufler-ca.com> Cc: Ming Lei <ming.lei@canonical.com> Cc: Takashi Iwai <tiwai@suse.de> Cc: Vojtěch Pavlík <vojtech@suse.cz> Cc: Kyle McMartin <kyle@kernel.org> Cc: Matthew Garrett <mjg59@srcf.ucam.org> Cc: linux-kernel@vger.kernel.org Signed-off-by: Luis R. Rodriguez <mcgrof@kernel.org> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com> Acked-by: Kees Cook <keescook@chromium.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-01-07firmware: actually return NULL on failed request_firmware_nowait()Brian Norris1-3/+5
The kerneldoc for request_firmware_nowait() says that it may call the provided cont() callback with @fw == NULL, if the firmware request fails. However, this is not the case when called with an empty string (""). This case is short-circuited by the 'name[0] == '\0'' check introduced in commit 471b095dfe0d ("firmware_class: make sure fw requests contain a name"), so _request_firmware() never gets to set the fw to NULL. Noticed while using the new 'trigger_async_request' testing hook: # printf '\x00' > /sys/devices/virtual/misc/test_firmware/trigger_async_request [10553.726178] test_firmware: loading '' [10553.729859] test_firmware: loaded: 995209091 # printf '\x00' > /sys/devices/virtual/misc/test_firmware/trigger_async_request [10733.676184] test_firmware: loading '' [10733.679855] Unable to handle kernel NULL pointer dereference at virtual address 00000004 [10733.687951] pgd = ec188000 [10733.690655] [00000004] *pgd=00000000 [10733.694240] Internal error: Oops: 5 [#1] SMP ARM [10733.698847] Modules linked in: btmrvl_sdio btmrvl bluetooth sbs_battery nf_conntrack_ipv6 nf_defrag_ipv6 ip6table_filter ip6_tables asix usbnet mwifiex_sdio mwifiex cfg80211 jitterentropy_rng drbg joydev snd_seq_midi snd_seq_midi_event snd_rawmidi snd_seq snd_seq_device ppp_async ppp_generic slhc tun [10733.725670] CPU: 0 PID: 6600 Comm: bash Not tainted 4.4.0-rc4-00351-g63d0877 #178 [10733.733137] Hardware name: Rockchip (Device Tree) [10733.737831] task: ed24f6c0 ti: ee322000 task.ti: ee322000 [10733.743222] PC is at do_raw_spin_lock+0x18/0x1a0 [10733.747831] LR is at _raw_spin_lock+0x18/0x1c [10733.752180] pc : [<c00653a0>] lr : [<c054c204>] psr: a00d0013 [10733.752180] sp : ee323df8 ip : ee323e20 fp : ee323e1c [10733.763634] r10: 00000051 r9 : b6f18000 r8 : ee323f80 [10733.768847] r7 : c089cebc r6 : 00000001 r5 : 00000000 r4 : ec0e6000 [10733.775360] r3 : dead4ead r2 : c06bd140 r1 : eef913b4 r0 : 00000000 [10733.781874] Flags: NzCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none [10733.788995] Control: 10c5387d Table: 2c18806a DAC: 00000051 [10733.794728] Process bash (pid: 6600, stack limit = 0xee322218) [10733.800549] Stack: (0xee323df8 to 0xee324000) [10733.804896] 3de0: ec0e6000 00000000 [10733.813059] 3e00: 00000001 c089cebc ee323f80 b6f18000 ee323e2c ee323e20 c054c204 c0065394 [10733.821221] 3e20: ee323e44 ee323e30 c02fec60 c054c1f8 ec0e7ec0 ec3fcfc0 ee323e5c ee323e48 [10733.829384] 3e40: c02fed08 c02fec48 c07dbf74 eeb05a00 ee323e8c ee323e60 c0253828 c02fecac [10733.837547] 3e60: 00000001 c0116950 ee323eac ee323e78 00000001 ec3fce00 ed2d9700 ed2d970c [10733.845710] 3e80: ee323e9c ee323e90 c02e873c c02537d4 ee323eac ee323ea0 c017bd40 c02e8720 [10733.853873] 3ea0: ee323ee4 ee323eb0 c017b250 c017bd00 00000000 00000000 f3e47a54 ec128b00 [10733.862035] 3ec0: c017b10c ee323f80 00000001 c000f504 ee322000 00000000 ee323f4c ee323ee8 [10733.870197] 3ee0: c011b71c c017b118 ee323fb0 c011bc90 becfa8d9 00000001 ec128b00 00000001 [10733.878359] 3f00: b6f18000 ee323f80 ee323f4c ee323f18 c011bc90 c0063950 ee323f3c ee323f28 [10733.886522] 3f20: c0063950 c0549138 00000001 ec128b00 00000001 ec128b00 b6f18000 ee323f80 [10733.894684] 3f40: ee323f7c ee323f50 c011bed8 c011b6ec c0135fb8 c0135f24 ec128b00 ec128b00 [10733.902847] 3f60: 00000001 b6f18000 c000f504 ee322000 ee323fa4 ee323f80 c011c664 c011be24 [10733.911009] 3f80: 00000000 00000000 00000001 b6f18000 b6e79be0 00000004 00000000 ee323fa8 [10733.919172] 3fa0: c000f340 c011c618 00000001 b6f18000 00000001 b6f18000 00000001 00000000 [10733.927334] 3fc0: 00000001 b6f18000 b6e79be0 00000004 00000001 00000001 8068a3f1 b6e79c84 [10733.935496] 3fe0: 00000000 becfa7dc b6de194d b6e20246 400d0030 00000001 7a4536e8 49bda390 [10733.943664] [<c00653a0>] (do_raw_spin_lock) from [<c054c204>] (_raw_spin_lock+0x18/0x1c) [10733.951743] [<c054c204>] (_raw_spin_lock) from [<c02fec60>] (fw_free_buf+0x24/0x64) [10733.959388] [<c02fec60>] (fw_free_buf) from [<c02fed08>] (release_firmware+0x68/0x74) [10733.967207] [<c02fed08>] (release_firmware) from [<c0253828>] (trigger_async_request_store+0x60/0x124) [10733.976501] [<c0253828>] (trigger_async_request_store) from [<c02e873c>] (dev_attr_store+0x28/0x34) [10733.985533] [<c02e873c>] (dev_attr_store) from [<c017bd40>] (sysfs_kf_write+0x4c/0x58) [10733.993437] [<c017bd40>] (sysfs_kf_write) from [<c017b250>] (kernfs_fop_write+0x144/0x1a8) [10734.001689] [<c017b250>] (kernfs_fop_write) from [<c011b71c>] (__vfs_write+0x3c/0xe4) After this patch: # printf '\x00' > /sys/devices/virtual/misc/test_firmware/trigger_async_request [ 32.126322] test_firmware: loading '' [ 32.129995] test_firmware: failed to async load firmware -bash: printf: write error: No such device Fixes: 471b095dfe0d ("firmware_class: make sure fw requests contain a name") Signed-off-by: Brian Norris <computersforpeace@gmail.com> Acked-by: Ming Lei <ming.lei@canonical.com> Acked-by: Kees Cook <keescook@chromium.org> Signed-off-by: Shuah Khan <shuahkh@osg.samsung.com>
2015-08-05firmware: fix wrong memory deallocation in fw_add_devm_name()Vladimir Zapolskiy1-1/+1
Device resource data allocated with devres_alloc() must be deallocated by devres_free(). Signed-off-by: Vladimir Zapolskiy <vz@mleia.com> Acked-by: Ming Lei <ming.lei@canonical.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-07-09Fix firmware loader uevent buffer NULL pointer dereferenceLinus Torvalds1-3/+13
The firmware class uevent function accessed the "fw_priv->buf" buffer without the proper locking and testing for NULL. This is an old bug (looks like it goes back to 2012 and commit 1244691c73b2: "firmware loader: introduce firmware_buf"), but for some reason it's triggering only now in 4.2-rc1. Shuah Khan is trying to bisect what it is that causes this to trigger more easily, but in the meantime let's just fix the bug since others are hitting it too (at least Ingo reports having seen it as well). Reported-and-tested-by: Shuah Khan <shuahkh@osg.samsung.com> Acked-by: Ming Lei <ming.lei@canonical.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-06-01firmware: add missing kfree for work on async callLuis R. Rodriguez1-1/+3
The recent fix to use kstrdup_const() failed to add a kfree upon failure of name allocation... Cc: Ming Lei <ming.lei@canonical.com> Cc: Seth Forshee <seth.forshee@canonical.com> Cc: Kyle McMartin <kyle@kernel.org> Signed-off-by: Luis R. Rodriguez <mcgrof@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-05-24firmware: use const for remaining firmware namesLuis R. Rodriguez1-12/+28
We currently use flexible arrays with a char at the end for the remaining internal firmware name uses. There are two limitations with the way we use this. Since we're using a flexible array for a string on the struct if we wanted to use two strings it means we'd have a disjoint means of handling the strings, one using the flexible array, and another a char * pointer. We're also currently not using 'const' for the string. We wish to later extend some firmware data structures with other string/char pointers, but we also want to be very pedantic about const usage. Since we're going to change things to use 'const' we might as well also address unified way to use multiple strings on the structs. Replace the flexible array practice for strings with kstrdup_const() and kfree_const(), this will avoid allocations when the vmlinux .rodata is used, and just allocate a new proper string for us when needed. This also means we can simplify the struct allocations by removing the string length from the allocation size computation, which would otherwise get even more complicated when supporting multiple strings. Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: David Howells <dhowells@redhat.com> Cc: Ming Lei <ming.lei@canonical.com> Cc: Seth Forshee <seth.forshee@canonical.com> Cc: Kyle McMartin <kyle@kernel.org> Signed-off-by: Luis R. Rodriguez <mcgrof@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-05-24firmware: fix possible use after free on name on asynchronous requestLuis R. Rodriguez1-1/+5
Asynchronous firmware loading copies the pointer to the name passed as an argument only to be scheduled later and used. This behaviour works well for synchronous calling but in asynchronous mode there's a chance the caller could immediately free the passed string after making the asynchronous call. This could trigger a use after free having the kernel look on disk for arbitrary file names. In order to force-test the issue you can use a test-driver designed to illustrate this issue on github [0], use the next-20150505-fix-use-after-free branch. With this patch applied you get: [ 283.512445] firmware name: test_module_stuff.bin [ 287.514020] firmware name: test_module_stuff.bin [ 287.532489] firmware found Without this patch applied you can end up with something such as: [ 135.624216] firmware name: \xffffff80BJ [ 135.624249] platform fake-dev.0: Direct firmware load for \xffffff80Bi failed with error -2 [ 135.624252] No firmware found [ 135.624252] firmware found Unfortunatley in the worst and most common case however you can typically crash your system with a page fault by trying to free something which you cannot, and/or a NULL pointer dereference [1]. The fix and issue using schedule_work() for asynchronous runs is generalized in the following SmPL grammar patch, when applied to next-20150505 only the firmware_class code is affected. This grammar patch can and should further be generalized to vet for for other kernel asynchronous mechanisms. @ calls_schedule_work @ type T; T *priv_work; identifier func, work_func; identifier work; identifier priv_name, name; expression gfp; @@ func(..., const char *name, ...) { ... priv_work = kzalloc(sizeof(T), gfp); ... - priv_work->priv_name = name; + priv_work->priv_name = kstrdup_const(name, gfp); ... (... when any if (...) { ... + kfree_const(priv_work->priv_name); kfree(priv_work); ... } ) ... when any INIT_WORK(&priv_work->work, work_func); ... schedule_work(&priv_work->work); ... } @ the_work_func depends on calls_schedule_work @ type calls_schedule_work.T; T *priv_work; identifier calls_schedule_work.work_func; identifier calls_schedule_work.priv_name; identifier calls_schedule_work.work; identifier some_work; @@ work_func(...) { ... priv_work = container_of(some_work, T, work); ... + kfree_const(priv_work->priv_name); kfree(priv_work); ... } [0] https://github.com/mcgrof/fake-firmware-test.git [1] The following kernel ring buffer splat: firmware name: test_module_stuff.bin firmware name: firmware found general protection fault: 0000 [#1] SMP Modules linked in: test(O) <...etc-it-does-not-matter> drm sr_mod cdrom xhci_pci xhci_hcd rtsx_pci mfd_core video button sg CPU: 3 PID: 87 Comm: kworker/3:2 Tainted: G O 4.0.0-00010-g22b5bb0-dirty #176 Hardware name: LENOVO 20AW000LUS/20AW000LUS, BIOS GLET43WW (1.18 ) 12/04/2013 Workqueue: events request_firmware_work_func task: ffff8800c7f8e290 ti: ffff8800c7f94000 task.ti: ffff8800c7f94000 RIP: 0010:[<ffffffff814a586c>] [<ffffffff814a586c>] fw_free_buf+0xc/0x40 RSP: 0000:ffff8800c7f97d78 EFLAGS: 00010286 RAX: ffffffff81ae3700 RBX: ffffffff816d1181 RCX: 0000000000000006 RDX: 0001ee850ff68500 RSI: 0000000000000246 RDI: c35d5f415e415d41 RBP: ffff8800c7f97d88 R08: 000000000000000a R09: 0000000000000000 R10: 0000000000000358 R11: ffff8800c7f97a7e R12: ffff8800c7ec1e80 R13: ffff88021e2d4cc0 R14: ffff88021e2dff00 R15: 00000000000000c0 FS: 0000000000000000(0000) GS:ffff88021e2c0000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00000000034b8cd8 CR3: 000000021073c000 CR4: 00000000001407e0 Stack: ffffffff816d1181 ffff8800c7ec1e80 ffff8800c7f97da8 ffffffff814a58f8 000000000000000a ffffffff816d1181 ffff8800c7f97dc8 ffffffffa047002c ffff88021e2dff00 ffff8802116ac1c0 ffff8800c7f97df8 ffffffff814a65fe Call Trace: [<ffffffff816d1181>] ? __schedule+0x361/0x940 [<ffffffff814a58f8>] release_firmware+0x58/0x80 [<ffffffff816d1181>] ? __schedule+0x361/0x940 [<ffffffffa047002c>] test_mod_cb+0x2c/0x43 [test] [<ffffffff814a65fe>] request_firmware_work_func+0x5e/0x80 [<ffffffff816d1181>] ? __schedule+0x361/0x940 [<ffffffff8108d23a>] process_one_work+0x14a/0x3f0 [<ffffffff8108d911>] worker_thread+0x121/0x460 [<ffffffff8108d7f0>] ? rescuer_thread+0x310/0x310 [<ffffffff810928f9>] kthread+0xc9/0xe0 [<ffffffff81092830>] ? kthread_create_on_node+0x180/0x180 [<ffffffff816d52d8>] ret_from_fork+0x58/0x90 [<ffffffff81092830>] ? kthread_create_on_node+0x180/0x180 Code: c7 c6 dd ad a3 81 48 c7 c7 20 97 ce 81 31 c0 e8 0b b2 ed ff e9 78 ff ff ff 66 0f 1f 44 00 00 0f 1f 44 00 00 55 48 89 e5 41 54 53 <4c> 8b 67 38 48 89 fb 4c 89 e7 e8 85 f7 22 00 f0 83 2b 01 74 0f RIP [<ffffffff814a586c>] fw_free_buf+0xc/0x40 RSP <ffff8800c7f97d78> ---[ end trace 4e62c56a58d0eac1 ]--- BUG: unable to handle kernel paging request at ffffffffffffffd8 IP: [<ffffffff81093ee0>] kthread_data+0x10/0x20 PGD 1c13067 PUD 1c15067 PMD 0 Oops: 0000 [#2] SMP Modules linked in: test(O) <...etc-it-does-not-matter> drm sr_mod cdrom xhci_pci xhci_hcd rtsx_pci mfd_core video button sg CPU: 3 PID: 87 Comm: kworker/3:2 Tainted: G D O 4.0.0-00010-g22b5bb0-dirty #176 Hardware name: LENOVO 20AW000LUS/20AW000LUS, BIOS GLET43WW (1.18 ) 12/04/2013 task: ffff8800c7f8e290 ti: ffff8800c7f94000 task.ti: ffff8800c7f94000 RIP: 0010:[<ffffffff81092ee0>] [<ffffffff81092ee0>] kthread_data+0x10/0x20 RSP: 0018:ffff8800c7f97b18 EFLAGS: 00010096 RAX: 0000000000000000 RBX: 0000000000000003 RCX: 000000000000000d RDX: 0000000000000003 RSI: 0000000000000003 RDI: ffff8800c7f8e290 RBP: ffff8800c7f97b18 R08: 000000000000bc00 R09: 0000000000007e76 R10: 0000000000000001 R11: 000000000000002f R12: ffff8800c7f8e290 R13: 00000000000154c0 R14: 0000000000000003 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff88021e2c0000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000028 CR3: 0000000210675000 CR4: 00000000001407e0 Stack: ffff8800c7f97b38 ffffffff8108dcd5 ffff8800c7f97b38 ffff88021e2d54c0 ffff8800c7f97b88 ffffffff816d1500 ffff880213d42368 ffff8800c7f8e290 ffff8800c7f97b88 ffff8800c7f97fd8 ffff8800c7f8e710 0000000000000246 Call Trace: [<ffffffff8108dcd5>] wq_worker_sleeping+0x15/0xa0 [<ffffffff816d1500>] __schedule+0x6e0/0x940 [<ffffffff816d1797>] schedule+0x37/0x90 [<ffffffff810779bc>] do_exit+0x6bc/0xb40 [<ffffffff8101898f>] oops_end+0x9f/0xe0 [<ffffffff81018efb>] die+0x4b/0x70 [<ffffffff81015622>] do_general_protection+0xe2/0x170 [<ffffffff816d74e8>] general_protection+0x28/0x30 [<ffffffff816d1181>] ? __schedule+0x361/0x940 [<ffffffff814a586c>] ? fw_free_buf+0xc/0x40 [<ffffffff816d1181>] ? __schedule+0x361/0x940 [<ffffffff814a58f8>] release_firmware+0x58/0x80 [<ffffffff816d1181>] ? __schedule+0x361/0x940 [<ffffffffa047002c>] test_mod_cb+0x2c/0x43 [test] [<ffffffff814a65fe>] request_firmware_work_func+0x5e/0x80 [<ffffffff816d1181>] ? __schedule+0x361/0x940 [<ffffffff8108d23a>] process_one_work+0x14a/0x3f0 [<ffffffff8108d911>] worker_thread+0x121/0x460 [<ffffffff8108d7f0>] ? rescuer_thread+0x310/0x310 [<ffffffff810928f9>] kthread+0xc9/0xe0 [<ffffffff81092830>] ? kthread_create_on_node+0x180/0x180 [<ffffffff816d52d8>] ret_from_fork+0x58/0x90 [<ffffffff81092830>] ? kthread_create_on_node+0x180/0x180 Code: 00 48 89 e5 5d 48 8b 40 c8 48 c1 e8 02 83 e0 01 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 8b 87 30 05 00 00 55 48 89 e5 <48> 8b 40 d8 5d c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 RIP [<ffffffff81092ee0>] kthread_data+0x10/0x20 RSP <ffff8800c7f97b18> CR2: ffffffffffffffd8 ---[ end trace 4e62c56a58d0eac2 ]--- Fixing recursive fault but reboot is needed! Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: David Howells <dhowells@redhat.com> Cc: Ming Lei <ming.lei@canonical.com> Cc: Seth Forshee <seth.forshee@canonical.com> Cc: Kyle McMartin <kyle@kernel.org> Generated-by: Coccinelle SmPL Signed-off-by: Luis R. Rodriguez <mcgrof@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-05-24firmware: check for file truncation on direct firmware loadingLuis R. Rodriguez1-2/+7
When direct firmware loading is used we iterate over a list of possible firmware paths and concatenate the desired firmware name with each path and look for the file there. Should the passed firmware name be too long we end up truncating the file we want to look for, the search however is still done. Add a check for truncation instead of looking for a truncated firmware filename. Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Ming Lei <ming.lei@canonical.com> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: David Howells <dhowells@redhat.com> Cc: Kyle McMartin <kyle@kernel.org> Signed-off-by: Luis R. Rodriguez <mcgrof@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-05-24firmware: fix __getname() missing failure checkLuis R. Rodriguez1-1/+5
The request_firmware*() APIs uses __getname() to iterate over the list of paths possible for firmware to be found, the code however never checked for failure on __getname(). Although *very unlikely*, this can still happen. Add the missing check. There is still no checks on the concatenation of the path and filename passed, that requires a bit more work and subsequent patches address this. The commit that introduced this is abb139e7 ("firmware: teach the kernel to load firmware files directly from the filesystem"). mcgrof@ergon ~/linux (git::firmware-fixes) $ git describe --contains abb139e7 v3.7-rc1~120 Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Ming Lei <ming.lei@canonical.com> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: David Howells <dhowells@redhat.com> Cc: Kyle McMartin <kyle@kernel.org> Signed-off-by: Luis R. Rodriguez <mcgrof@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-03-25drivers: base: fw: fix ret value when loading fwZahari Doychev1-0/+2
When using the user mode helper to load firmwares the function _request_firmware gets a positive return value from fw_load_from_user_helper and because of this the firmware buffer is not assigned. This happens only when the return value is zero. This patch fixes this problem in _request_firmware_load. When the completion is ready the return value is set to zero. Signed-off-by: Zahari Doychev <zahari.doychev@linux.com> Cc: Ming Lei <ming.lei@canonical.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-03-25firmware: Avoid manual device_create_file() callsTakashi Iwai1-19/+21
Use the static attribute groups assigned to the device instead of manual device_create_file() & co calls. It simplifies the code and can avoid possible races, too. Signed-off-by: Takashi Iwai <tiwai@suse.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-03-25firmware_class: Fix whitespace and indentationAndrei Oprea1-3/+4
Fix checkpatch.pl issues with coding style. Removed whitespace and fixed indentation Signed-off-by: Andrei Oprea <andrei.br92@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-02-15Merge tag 'driver-core-3.20-rc1' of ↵Linus Torvalds1-22/+11
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core Pull driver core patches from Greg KH: "Really tiny set of patches for this kernel. Nothing major, all described in the shortlog and have been in linux-next for a while" * tag 'driver-core-3.20-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: sysfs: fix warning when creating a sysfs group without attributes firmware_loader: handle timeout via wait_for_completion_interruptible_timeout() firmware_loader: abort request if wait_for_completion is interrupted firmware: Correct function name in comment device: Change dev_<level> logging functions to return void device: Fix dev_dbg_once macro
2015-02-12PM / OPP / clk: Remove unnecessary OOM messageQuentin Lambert1-1/+0
This patch reduces the kernel size by removing error messages that duplicate the normal OOM message. A simplified version of the semantic patch that finds this problem is as follows: (http://coccinelle.lip6.fr) @@ identifier f,print,l; expression e; constant char[] c; @@ e = \(kzalloc\|kmalloc\|devm_kzalloc\|devm_kmalloc\)(...); if (e == NULL) { <+... - print(...,c,...); ... when any ( goto l; | return ...; ) ...+> } Signed-off-by: Quentin Lambert <lambert.quentin@gmail.com> Acked-by: Nishanth Menon <nm@ti.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-02-03firmware_loader: handle timeout via wait_for_completion_interruptible_timeout()Ming Lei1-24/+6
It is simpler to handle timeout by wait_for_completion_interruptible_timeout(), so remove previous delay work for timeout. Signed-off-by: Ming Lei <ming.lei@canonical.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-02-03firmware_loader: abort request if wait_for_completion is interruptedMing Lei1-0/+7
If current request is interrupted by signal, such as 'ctrl + c', this request has to be aborted for the following reasons: - the buf need to be removed from pending list - same requests from other contexts need to be completed Reported-by: Sasha Levin <sasha.levin@oracle.com> Signed-off-by: Ming Lei <ming.lei@canonical.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-02-03firmware: Correct function name in commentBorislav Petkov1-1/+1
Use the correct function name in the kernel-doc comment above it. Signed-off-by: Borislav Petkov <bp@suse.de> Acked-by: Ming Lei <ming.lei@canonical.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>