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2014-08-06iommu/vt-d: Disable translation if already enabledTakao Indoh
commit 3a93c841c2b3b14824f7728dd74bd00a1cedb806 upstream. This patch disables translation(dma-remapping) before its initialization if it is already enabled. This is needed for kexec/kdump boot. If dma-remapping is enabled in the first kernel, it need to be disabled before initializing its page table during second kernel boot. Wei Hu also reported that this is needed when second kernel boots with intel_iommu=off. Basically iommu->gcmd is used to know whether translation is enabled or disabled, but it is always zero at boot time even when translation is enabled since iommu->gcmd is initialized without considering such a case. Therefor this patch synchronizes iommu->gcmd value with global command register when iommu structure is allocated. Signed-off-by: Takao Indoh <indou.takao@jp.fujitsu.com> Signed-off-by: Joerg Roedel <joro@8bytes.org> [wyj: Backported to 3.4: adjust context] Signed-off-by: Yijing Wang <wangyijing@huawei.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2014-08-06libata: introduce ata_host->n_tags to avoid oops on SAS controllersTejun Heo
commit 1a112d10f03e83fb3a2fdc4c9165865dec8a3ca6 upstream. 1871ee134b73 ("libata: support the ata host which implements a queue depth less than 32") directly used ata_port->scsi_host->can_queue from ata_qc_new() to determine the number of tags supported by the host; unfortunately, SAS controllers doing SATA don't initialize ->scsi_host leading to the following oops. BUG: unable to handle kernel NULL pointer dereference at 0000000000000058 IP: [<ffffffff814e0618>] ata_qc_new_init+0x188/0x1b0 PGD 0 Oops: 0002 [#1] SMP Modules linked in: isci libsas scsi_transport_sas mgag200 drm_kms_helper ttm CPU: 1 PID: 518 Comm: udevd Not tainted 3.16.0-rc6+ #62 Hardware name: Intel Corporation S2600CO/S2600CO, BIOS SE5C600.86B.02.02.0002.122320131210 12/23/2013 task: ffff880c1a00b280 ti: ffff88061a000000 task.ti: ffff88061a000000 RIP: 0010:[<ffffffff814e0618>] [<ffffffff814e0618>] ata_qc_new_init+0x188/0x1b0 RSP: 0018:ffff88061a003ae8 EFLAGS: 00010012 RAX: 0000000000000001 RBX: ffff88000241ca80 RCX: 00000000000000fa RDX: 0000000000000020 RSI: 0000000000000020 RDI: ffff8806194aa298 RBP: ffff88061a003ae8 R08: ffff8806194a8000 R09: 0000000000000000 R10: 0000000000000000 R11: ffff88000241ca80 R12: ffff88061ad58200 R13: ffff8806194aa298 R14: ffffffff814e67a0 R15: ffff8806194a8000 FS: 00007f3ad7fe3840(0000) GS:ffff880627620000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000058 CR3: 000000061a118000 CR4: 00000000001407e0 Stack: ffff88061a003b20 ffffffff814e96e1 ffff88000241ca80 ffff88061ad58200 ffff8800b6bf6000 ffff880c1c988000 ffff880619903850 ffff88061a003b68 ffffffffa0056ce1 ffff88061a003b48 0000000013d6e6f8 ffff88000241ca80 Call Trace: [<ffffffff814e96e1>] ata_sas_queuecmd+0xa1/0x430 [<ffffffffa0056ce1>] sas_queuecommand+0x191/0x220 [libsas] [<ffffffff8149afee>] scsi_dispatch_cmd+0x10e/0x300 [<ffffffff814a3bc5>] scsi_request_fn+0x2f5/0x550 [<ffffffff81317613>] __blk_run_queue+0x33/0x40 [<ffffffff8131781a>] queue_unplugged+0x2a/0x90 [<ffffffff8131ceb4>] blk_flush_plug_list+0x1b4/0x210 [<ffffffff8131d274>] blk_finish_plug+0x14/0x50 [<ffffffff8117eaa8>] __do_page_cache_readahead+0x198/0x1f0 [<ffffffff8117ee21>] force_page_cache_readahead+0x31/0x50 [<ffffffff8117ee7e>] page_cache_sync_readahead+0x3e/0x50 [<ffffffff81172ac6>] generic_file_read_iter+0x496/0x5a0 [<ffffffff81219897>] blkdev_read_iter+0x37/0x40 [<ffffffff811e307e>] new_sync_read+0x7e/0xb0 [<ffffffff811e3734>] vfs_read+0x94/0x170 [<ffffffff811e43c6>] SyS_read+0x46/0xb0 [<ffffffff811e33d1>] ? SyS_lseek+0x91/0xb0 [<ffffffff8171ee29>] system_call_fastpath+0x16/0x1b Code: 00 00 00 88 50 29 83 7f 08 01 19 d2 83 e2 f0 83 ea 50 88 50 34 c6 81 1d 02 00 00 40 c6 81 17 02 00 00 00 5d c3 66 0f 1f 44 00 00 <89> 14 25 58 00 00 00 Fix it by introducing ata_host->n_tags which is initialized to ATA_MAX_QUEUE - 1 in ata_host_init() for SAS controllers and set to scsi_host_template->can_queue in ata_host_register() for !SAS ones. As SAS hosts are never registered, this will give them the same ATA_MAX_QUEUE - 1 as before. Note that we can't use scsi_host->can_queue directly for SAS hosts anyway as they can go higher than the libata maximum. Signed-off-by: Tejun Heo <tj@kernel.org> Reported-by: Mike Qiu <qiudayu@linux.vnet.ibm.com> Reported-by: Jesse Brandeburg <jesse.brandeburg@gmail.com> Reported-by: Peter Hurley <peter@hurleysoftware.com> Reported-by: Peter Zijlstra <peterz@infradead.org> Tested-by: Alexey Kardashevskiy <aik@ozlabs.ru> Fixes: 1871ee134b73 ("libata: support the ata host which implements a queue depth less than 32") Cc: Kevin Hao <haokexin@gmail.com> Cc: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2014-08-06libata: support the ata host which implements a queue depth less than 32Kevin Hao
commit 1871ee134b73fb4cadab75752a7152ed2813c751 upstream. The sata on fsl mpc8315e is broken after the commit 8a4aeec8d2d6 ("libata/ahci: accommodate tag ordered controllers"). The reason is that the ata controller on this SoC only implement a queue depth of 16. When issuing the commands in tag order, all the commands in tag 16 ~ 31 are mapped to tag 0 unconditionally and then causes the sata malfunction. It makes no senses to use a 32 queue in software while the hardware has less queue depth. So consider the queue depth implemented by the hardware when requesting a command tag. Fixes: 8a4aeec8d2d6 ("libata/ahci: accommodate tag ordered controllers") Signed-off-by: Kevin Hao <haokexin@gmail.com> Acked-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2014-08-06sym53c8xx_2: Set DID_REQUEUE return code when aborting squeueMikulas Patocka
commit fd1232b214af43a973443aec6a2808f16ee5bf70 upstream. This patch fixes I/O errors with the sym53c8xx_2 driver when the disk returns QUEUE FULL status. When the controller encounters an error (including QUEUE FULL or BUSY status), it aborts all not yet submitted requests in the function sym_dequeue_from_squeue. This function aborts them with DID_SOFT_ERROR. If the disk has full tag queue, the request that caused the overflow is aborted with QUEUE FULL status (and the scsi midlayer properly retries it until it is accepted by the disk), but the sym53c8xx_2 driver aborts the following requests with DID_SOFT_ERROR --- for them, the midlayer does just a few retries and then signals the error up to sd. The result is that disk returning QUEUE FULL causes request failures. The error was reproduced on 53c895 with COMPAQ BD03685A24 disk (rebranded ST336607LC) with command queue 48 or 64 tags. The disk has 64 tags, but under some access patterns it return QUEUE FULL when there are less than 64 pending tags. The SCSI specification allows returning QUEUE FULL anytime and it is up to the host to retry. Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Cc: Matthew Wilcox <matthew@wil.cx> Cc: James Bottomley <JBottomley@Parallels.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-08-06applicom: dereferencing NULL on error pathDan Carpenter
commit 8bab797c6e5724a43b7666ad70860712365cdb71 upstream. This is a static checker fix. The "dev" variable is always NULL after the while statement so we would be dereferencing a NULL pointer here. Fixes: 819a3eba4233 ('[PATCH] applicom: fix error handling') Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2014-08-06sunvnet: clean up objects created in vnet_new() on vnet_exit()Sowmini Varadhan
[ Upstream commit a4b70a07ed12a71131cab7adce2ce91c71b37060 ] Nothing cleans up the objects created by vnet_new(), they are completely leaked. vnet_exit(), after doing the vio_unregister_driver() to clean up ports, should call a helper function that iterates over vnet_list and cleans up those objects. This includes unregister_netdevice() as well as free_netdev(). Signed-off-by: Sowmini Varadhan <sowmini.varadhan@oracle.com> Acked-by: Dave Kleikamp <dave.kleikamp@oracle.com> Reviewed-by: Karl Volz <karl.volz@oracle.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2014-08-06usb: Check if port status is equal to RxDetectGavin Guo
commit bb86cf569bbd7ad4dce581a37c7fbd748057e9dc upstream. When using USB 3.0 pen drive with the [AMD] FCH USB XHCI Controller [1022:7814], the second hotplugging will experience the USB 3.0 pen drive is recognized as high-speed device. After bisecting the kernel, I found the commit number 41e7e056cdc662f704fa9262e5c6e213b4ab45dd (USB: Allow USB 3.0 ports to be disabled.) causes the bug. After doing some experiments, the bug can be fixed by avoiding executing the function hub_usb3_port_disable(). Because the port status with [AMD] FCH USB XHCI Controlleris [1022:7814] is already in RxDetect (I tried printing out the port status before setting to Disabled state), it's reasonable to check the port status before really executing hub_usb3_port_disable(). Fixes: 41e7e056cdc6 (USB: Allow USB 3.0 ports to be disabled.) Signed-off-by: Gavin Guo <gavin.guo@canonical.com> Acked-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> [bwh: Backported to 3.2: use hub device as context for dev_dbg(), as hub ports are not devices in their own right] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2014-08-06drm/radeon: avoid leaking edid dataAlex Deucher
commit 0ac66effe7fcdee55bda6d5d10d3372c95a41920 upstream. In some cases we fetch the edid in the detect() callback in order to determine what sort of monitor is connected. If that happens, don't fetch the edid again in the get_modes() callback or we will leak the edid. Signed-off-by: Alex Deucher <alexander.deucher@amd.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2014-08-06hwmon: (adt7470) Fix writes to temperature limit registersGuenter Roeck
commit de12d6f4b10b21854441f5242dcb29ea96181e58 upstream. Temperature limit registers are signed. Limits therefore need to be clamped to (-128, 127) degrees C and not to (0, 255) degrees C. Without this fix, writing a limit of 128 degrees C sets the actual limit to -128 degrees C. Signed-off-by: Guenter Roeck <linux@roeck-us.net> Reviewed-by: Axel Lin <axel.lin@ingics.com> [bwh: Backported to 3.2: driver was using SENSORS_LIMIT(), which we can replace with clamp_val()] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2014-08-06drm/radeon/dp: return -EIO for flags not zero caseAlex Deucher
commit f6be5e64500abbba44e191e1ca0f3366c7d0291b upstream. If there are error flags in the aux transaction return -EIO rather than -EBUSY. -EIO restarts the whole transaction while -EBUSY jus retries. Fixes problematic aux transfers. Bug: https://bugs.freedesktop.org/show_bug.cgi?id=80684 Signed-off-by: Alex Deucher <alexander.deucher@amd.com> [bwh: Backported to 3.2: error code is returned directly here] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2014-08-06dm io: fix a race condition in the wake up code for sync_ioJoe Thornber
commit 10f1d5d111e8aed46a0f1179faf9a3cf422f689e upstream. There's a race condition between the atomic_dec_and_test(&io->count) in dec_count() and the waking of the sync_io() thread. If the thread is spuriously woken immediately after the decrement it may exit, making the on stack io struct invalid, yet the dec_count could still be using it. Fix this race by using a completion in sync_io() and dec_count(). Reported-by: Minfei Huang <huangminfei@ucloud.cn> Signed-off-by: Joe Thornber <thornber@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com> Acked-by: Mikulas Patocka <mpatocka@redhat.com> [bwh: Backported to 3.2: use wait_for_completion() as wait_for_completion_io() is not available] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2014-08-06igb: do a reset on SR-IOV re-init if device is downStefan Assmann
commit 76252723e88681628a3dbb9c09c963e095476f73 upstream. To properly re-initialize SR-IOV it is necessary to reset the device even if it is already down. Not doing this may result in Tx unit hangs. Signed-off-by: Stefan Assmann <sassmann@kpanic.de> Tested-by: Aaron Brown <aaron.f.brown@intel.com> Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2014-08-06USB: ftdi_sio: Add extra PID.Bert Vermeulen
commit 5a7fbe7e9ea0b1b9d7ffdba64db1faa3a259164c upstream. This patch adds PID 0x0003 to the VID 0x128d (Testo). At least the Testo 435-4 uses this, likely other gear as well. Signed-off-by: Bert Vermeulen <bert@biot.com> Cc: Johan Hovold <johan@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2014-08-06hwmon: (emc2103) Clamp limits instead of bailing outGuenter Roeck
commit f6c2dd20108c35e30e2c1f3c6142d189451a626b upstream. It is customary to clamp limits instead of bailing out with an error if a configured limit is out of the range supported by the driver. This simplifies limit configuration, since the user will not typically know chip and/or driver specific limits. Reviewed-by: Jean Delvare <jdelvare@suse.de> Signed-off-by: Guenter Roeck <linux@roeck-us.net> [bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2014-08-06hwmon: (adm1031) Fix writes to limit registersGuenter Roeck
commit 145e74a4e5022225adb84f4e5d4fff7938475c35 upstream. Upper limit for write operations to temperature limit registers was clamped to a fractional value. However, limit registers do not support fractional values. As a result, upper limits of 127.5 degrees C or higher resulted in a rounded limit of 128 degrees C. Since limit registers are signed, this was stored as -128 degrees C. Clamp limits to (-55, +127) degrees C to solve the problem. Value on writes to auto_temp[12]_min and auto_temp[12]_max were not clamped at all, but masked. As a result, out-of-range writes resulted in a more or less arbitrary limit. Clamp those attributes to (0, 127) degrees C for more predictable results. Cc: Axel Lin <axel.lin@ingics.com> Reviewed-by: Jean Delvare <jdelvare@suse.de> Signed-off-by: Guenter Roeck <linux@roeck-us.net> [bwh: Backported to 3.2: - Adjust context - Driver was using SENSORS_LIMIT(), which we can replace with clamp_val()] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2014-08-06ACPI / battery: Retry to get battery information if failed during probingLan Tianyu
commit 75646e758a0ecbed5024454507d5be5b9ea9dcbf upstream. Some machines (eg. Lenovo Z480) ECs are not stable during boot up and causes battery driver fails to be loaded due to failure of getting battery information from EC sometimes. After several retries, the operation will work. This patch is to retry to get battery information 5 times if the first try fails. Link: https://bugzilla.kernel.org/show_bug.cgi?id=75581 Reported-and-tested-by: naszar <naszar@ya.ru> Signed-off-by: Lan Tianyu <tianyu.lan@intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> [bwh: Backported to 3.2: acpi_battery_update() doesn't take a second parameter] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2014-08-06ACPI / EC: Fix race condition in ec_transaction_completed()Lv Zheng
commit c0d653412fc8450370167a3268b78fc772ff9c87 upstream. There is a race condition in ec_transaction_completed(). When ec_transaction_completed() is called in the GPE handler, it could return true because of (ec->curr == NULL). Then the wake_up() invocation could complete the next command unexpectedly since there is no lock between the 2 invocations. With the previous cleanup, the IBF=0 waiter race need not be handled any more. It's now safe to return a flag from advance_condition() to indicate the requirement of wakeup, the flag is returned from a locked context. The ec_transaction_completed() is now only invoked by the ec_poll() where the ec->curr is ensured to be different from NULL. After cleaning up, the EVT_SCI=1 check should be moved out of the wakeup condition so that an EVT_SCI raised with (ec->curr == NULL) can trigger a QR_SC command. Link: https://bugzilla.kernel.org/show_bug.cgi?id=70891 Link: https://bugzilla.kernel.org/show_bug.cgi?id=63931 Link: https://bugzilla.kernel.org/show_bug.cgi?id=59911 Reported-and-tested-by: Gareth Williams <gareth@garethwilliams.me.uk> Reported-and-tested-by: Hans de Goede <jwrdegoede@fedoraproject.org> Reported-by: Barton Xu <tank.xuhan@gmail.com> Tested-by: Steffen Weber <steffen.weber@gmail.com> Tested-by: Arthur Chen <axchen@nvidia.com> Signed-off-by: Lv Zheng <lv.zheng@intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> [bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2014-08-06ACPI / EC: Remove duplicated ec_wait_ibf0() waiterLv Zheng
commit 9b80f0f73ae1583c22325ede341c74195847618c upstream. After we've added the first command byte write into advance_transaction(), the IBF=0 waiter is duplicated with the command completion waiter implemented in the ec_poll() because: If IBF=1 blocked the first command byte write invoked in the task context ec_poll(), it would be kicked off upon IBF=0 interrupt or timed out and retried again in the task context. Remove this seperate and duplicate IBF=0 waiter. By doing so we can reduce the overall number of times to access the EC_SC(R) status register. Link: https://bugzilla.kernel.org/show_bug.cgi?id=70891 Link: https://bugzilla.kernel.org/show_bug.cgi?id=63931 Link: https://bugzilla.kernel.org/show_bug.cgi?id=59911 Reported-and-tested-by: Gareth Williams <gareth@garethwilliams.me.uk> Reported-and-tested-by: Hans de Goede <jwrdegoede@fedoraproject.org> Reported-by: Barton Xu <tank.xuhan@gmail.com> Tested-by: Steffen Weber <steffen.weber@gmail.com> Tested-by: Arthur Chen <axchen@nvidia.com> Signed-off-by: Lv Zheng <lv.zheng@intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> [bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2014-08-06ACPI / EC: Add asynchronous command byte write supportLv Zheng
commit f92fca0060fc4dc9227342d0072d75df98c1e5a5 upstream. Move the first command byte write into advance_transaction() so that all EC register accesses that can affect the command processing state machine can happen in this asynchronous state machine advancement function. The advance_transaction() function then can be a complete implementation of an asyncrhonous transaction for a single command so that: 1. The first command byte can be written in the interrupt context; 2. The command completion waiter can also be used to wait the first command byte's timeout; 3. In BURST mode, the follow-up command bytes can be written in the interrupt context directly, so that it doesn't need to return to the task context. Returning to the task context reduces the throughput of the BURST mode and in the worst cases where the system workload is very high, this leads to the hardware driven automatic BURST mode exit. In order not to increase memory consumption, convert 'done' into 'flags' to contain multiple indications: 1. ACPI_EC_COMMAND_COMPLETE: converting from original 'done' condition, indicating the completion of the command transaction. 2. ACPI_EC_COMMAND_POLL: indicating the availability of writing the first command byte. A new command can utilize this flag to compete for the right of accessing the underlying hardware. There is a follow-up bug fix that has utilized this new flag. The 2 flags are important because it also reflects a key concept of IO programs' design used in the system softwares. Normally an IO program running in the kernel should first be implemented in the asynchronous way. And the 2 flags are the most common way to implement its synchronous operations on top of the asynchronous operations: 1. POLL: This flag can be used to block until the asynchronous operations can happen. 2. COMPLETE: This flag can be used to block until the asynchronous operations have completed. By constructing code cleanly in this way, many difficult problems can be solved smoothly. Link: https://bugzilla.kernel.org/show_bug.cgi?id=70891 Link: https://bugzilla.kernel.org/show_bug.cgi?id=63931 Link: https://bugzilla.kernel.org/show_bug.cgi?id=59911 Reported-and-tested-by: Gareth Williams <gareth@garethwilliams.me.uk> Reported-and-tested-by: Hans de Goede <jwrdegoede@fedoraproject.org> Reported-by: Barton Xu <tank.xuhan@gmail.com> Tested-by: Steffen Weber <steffen.weber@gmail.com> Tested-by: Arthur Chen <axchen@nvidia.com> Signed-off-by: Lv Zheng <lv.zheng@intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> [bwh: Backported to 3.2: - Adjust context - s/ec->lock/ec->curr_lock/] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2014-08-06ACPI / EC: Don't count a SCI interrupt as a false oneFeng Tang
commit a3cd8d2789c2e265e09377f260e7d2ac9cec81bb upstream. Currently when advance_transaction() is called in EC interrupt handler, if there is nothing driver can do with the interrupt, it will be taken as a false one. But this is not always true, as there may be a SCI EC interrupt fired during normal read/write operation, which should not be counted as a false one. This patch fixes the problem. Signed-off-by: Feng Tang <feng.tang@intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2014-08-06ACPI / EC: Avoid race condition related to advance_transaction()Lv Zheng
commit 66b42b78bc1e816f92b662e8888c89195e4199e1 upstream. The advance_transaction() will be invoked from the IRQ context GPE handler and the task context ec_poll(). The handling of this function is locked so that the EC state machine are ensured to be advanced sequentially. But there is a problem. Before invoking advance_transaction(), EC_SC(R) is read. Then for advance_transaction(), there could be race condition around the lock from both contexts. The first one reading the register could fail this race and when it passes the stale register value to the state machine advancement code, the hardware condition is totally different from when the register is read. And the hardware accesses determined from the wrong hardware status can break the EC state machine. And there could be cases that the functionalities of the platform firmware are seriously affected. For example: 1. When 2 EC_DATA(W) writes compete the IBF=0, the 2nd EC_DATA(W) write may be invalid due to IBF=1 after the 1st EC_DATA(W) write. Then the hardware will either refuse to respond a next EC_SC(W) write of the next command or discard the current WR_EC command when it receives a EC_SC(W) write of the next command. 2. When 1 EC_SC(W) write and 1 EC_DATA(W) write compete the IBF=0, the EC_DATA(W) write may be invalid due to IBF=1 after the EC_SC(W) write. The next EC_DATA(R) could never be responded by the hardware. This is the root cause of the reported issue. Fix this issue by moving the EC_SC(R) access into the lock so that we can ensure that the state machine is advanced consistently. Link: https://bugzilla.kernel.org/show_bug.cgi?id=70891 Link: https://bugzilla.kernel.org/show_bug.cgi?id=63931 Link: https://bugzilla.kernel.org/show_bug.cgi?id=59911 Reported-and-tested-by: Gareth Williams <gareth@garethwilliams.me.uk> Reported-and-tested-by: Hans de Goede <jwrdegoede@fedoraproject.org> Reported-by: Barton Xu <tank.xuhan@gmail.com> Tested-by: Steffen Weber <steffen.weber@gmail.com> Tested-by: Arthur Chen <axchen@nvidia.com> Signed-off-by: Lv Zheng <lv.zheng@intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> [bwh: Backported to 3.2: - Adjust context - Use PREFIX in log message] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2014-08-06ACPI / EC: Ensure lock is acquired before accessing ec struct membersPuneet Kumar
commit 36b15875a7819a2ec4cb5748ff7096ad7bd86cbb upstream. A bug was introduced by commit b76b51ba0cef ('ACPI / EC: Add more debug info and trivial code cleanup') that erroneously caused the struct member to be accessed before acquiring the required lock. This change fixes it by ensuring the lock acquisition is done first. Found by Aaron Durbin <adurbin@chromium.org> Fixes: b76b51ba0cef ('ACPI / EC: Add more debug info and trivial code cleanup') References: http://crbug.com/319019 Signed-off-by: Puneet Kumar <puneetster@chromium.org> Reviewed-by: Aaron Durbin <adurbin@chromium.org> [olof: Commit message reworded a bit] Signed-off-by: Olof Johansson <olof@lixom.net> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> [bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2014-08-06ACPI / EC: Add more debug info and trivial code cleanupFeng Tang
commit b76b51ba0cef13980813373a548a12206e3cd3c9 upstream. Add more debug info for EC transaction debugging, like the interrupt status register value, the detail info of a EC transaction. Signed-off-by: Feng Tang <feng.tang@intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> [bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2014-08-06usb: option: Add ID for Telewell TW-LTE 4G v2Bernd Wachter
commit 3d28bd840b2d3981cd28caf5fe1df38f1344dd60 upstream. Add ID of the Telewell 4G v2 hardware to option driver to get legacy serial interface working Signed-off-by: Bernd Wachter <bernd.wachter@jolla.com> Signed-off-by: Johan Hovold <johan@kernel.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2014-08-06USB: cp210x: add support for Corsair usb dongleAndras Kovacs
commit b9326057a3d8447f5d2e74a7b521ccf21add2ec0 upstream. Corsair USB Dongles are shipped with Corsair AXi series PSUs. These are cp210x serial usb devices, so make driver detect these. I have a program, that can get information from these PSUs. Tested with 2 different dongles shipped with Corsair AX860i and AX1200i units. Signed-off-by: Andras Kovacs <andras@sth.sze.hu> Signed-off-by: Johan Hovold <johan@kernel.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2014-08-06hwmon: (adm1029) Ensure the fan_div cache is updated in set_fan_divAxel Lin
commit 1035a9e3e9c76b64a860a774f5b867d28d34acc2 upstream. Writing to fanX_div does not clear the cache. As a result, reading from fanX_div may return the old value for up to two seconds after writing a new value. This patch ensures the fan_div cache is updated in set_fan_div(). Reported-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Axel Lin <axel.lin@ingics.com> Signed-off-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2014-08-06hwmon: (amc6821) Fix permissions for temp2_inputAxel Lin
commit df86754b746e9a0ff6f863f690b1c01d408e3cdc upstream. temp2_input should not be writable, fix it. Reported-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Axel Lin <axel.lin@ingics.com> Signed-off-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2014-08-06drm/vmwgfx: Fix incorrect write to read-only register v2:Thomas Hellstrom
commit 4e578080ed3262ed2c3985868539bc66218d25c0 upstream. Commit "drm/vmwgfx: correct fb_fix_screeninfo.line_length", while fixing a vmwgfx fbdev bug, also writes the pitch to a supposedly read-only register: SVGA_REG_BYTES_PER_LINE, while it should be (and also in fact is) written to SVGA_REG_PITCHLOCK. This patch is Cc'd stable because of the unknown effects writing to this register might have, particularly on older device versions. v2: Updated log message. Cc: Christopher Friedt <chrisfriedt@gmail.com> Tested-by: Christopher Friedt <chrisfriedt@gmail.com> Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com> Reviewed-by: Jakob Bornecrantz <jakob@vmware.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2014-08-06iwlwifi: dvm: don't enable CTS to selfEmmanuel Grumbach
commit 43d826ca5979927131685cc2092c7ce862cb91cd upstream. We should always prefer to use full RTS protection. Using CTS to self gives a meaningless improvement, but this flow is much harder for the firmware which is likely to have issues with it. Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com> [bwh: Backported to 3.2: - Adjust filename - Condition for RXON_FLG_SELF_CTS_EN in iwlagn_commit_rxon() was different] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2014-08-06xen/manage: fix potential deadlock when resuming the consoleDavid Vrabel
commit 1b6478231c6f5f844185acb32045cf195028cfce upstream. Calling xen_console_resume() in xen_suspend() causes a warning because it locks irq_mapping_update_lock (a mutex) and this may sleep. If a userspace process is using the evtchn device then this mutex may be locked at the point of the stop_machine() call and xen_console_resume() would then deadlock. Resuming the console after stop_machine() returns avoids this deadlock. Signed-off-by: David Vrabel <david.vrabel@citrix.com> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> [bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2014-08-06md: flush writes before starting a recovery.NeilBrown
commit 133d4527eab8d199a62eee6bd433f0776842df2e upstream. When we write to a degraded array which has a bitmap, we make sure the relevant bit in the bitmap remains set when the write completes (so a 're-add' can quickly rebuilt a temporarily-missing device). If, immediately after such a write starts, we incorporate a spare, commence recovery, and skip over the region where the write is happening (because the 'needs recovery' flag isn't set yet), then that write will not get to the new device. Once the recovery finishes the new device will be trusted, but will have incorrect data, leading to possible corruption. We cannot set the 'needs recovery' flag when we start the write as we do not know easily if the write will be "degraded" or not. That depends on details of the particular raid level and particular write request. This patch fixes a corruption issue of long standing and so it suitable for any -stable kernel. It applied correctly to 3.0 at least and will minor editing to earlier kernels. Reported-by: Bill <billstuff2001@sbcglobal.net> Tested-by: Bill <billstuff2001@sbcglobal.net> Link: http://lkml.kernel.org/r/53A518BB.60709@sbcglobal.net Signed-off-by: NeilBrown <neilb@suse.de> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2014-08-06usb-storage/SCSI: Add broken_fua blacklist flagAlan Stern
commit b14bf2d0c0358140041d1c1805a674376964d0e0 upstream. Some buggy JMicron USB-ATA bridges don't know how to translate the FUA bit in READs or WRITEs. This patch adds an entry in unusual_devs.h and a blacklist flag to tell the sd driver not to use FUA. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Reported-by: Michael Büsch <m@bues.ch> Tested-by: Michael Büsch <m@bues.ch> Acked-by: James Bottomley <James.Bottomley@HansenPartnership.com> CC: Matthew Dharm <mdharm-usb@one-eyed-alien.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> [bwh: Backported to 3.2: - Adjust context - Use sd_printk() not sd_first_printk()] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2014-08-06mwifiex: fix Tx timeout issueAmitkumar Karwar
commit d76744a93246eccdca1106037e8ee29debf48277 upstream. https://bugzilla.kernel.org/show_bug.cgi?id=70191 https://bugzilla.kernel.org/show_bug.cgi?id=77581 It is observed that sometimes Tx packet is downloaded without adding driver's txpd header. This results in firmware parsing garbage data as packet length. Sometimes firmware is unable to read the packet if length comes out as invalid. This stops further traffic and timeout occurs. The root cause is uninitialized fields in tx_info(skb->cb) of packet used to get garbage values. In this case if MWIFIEX_BUF_FLAG_REQUEUED_PKT flag is mistakenly set, txpd header was skipped. This patch makes sure that tx_info is correctly initialized to fix the problem. Reported-by: Andrew Wiley <wiley.andrew.j@gmail.com> Reported-by: Linus Gasser <list@markas-al-nour.org> Reported-by: Michael Hirsch <hirsch@teufel.de> Tested-by: Xinming Hu <huxm@marvell.com> Signed-off-by: Amitkumar Karwar <akarwar@marvell.com> Signed-off-by: Maithili Hinge <maithili@marvell.com> Signed-off-by: Avinash Patil <patila@marvell.com> Signed-off-by: Bing Zhao <bzhao@marvell.com> Signed-off-by: John W. Linville <linville@tuxdriver.com> [bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2014-08-06ibmvscsi: Add memory barriers for send / receiveBrian King
commit 7114aae02742d6b5c5a0d39a41deb61d415d3717 upstream. Add a memory barrier prior to sending a new command to the VIOS to ensure the VIOS does not receive stale data in the command buffer. Also add a memory barrier when processing the CRQ for completed commands. Signed-off-by: Brian King <brking@linux.vnet.ibm.com> Acked-by: Nathan Fontenot <nfont@linux.vnet.ibm.com> Signed-off-by: Christoph Hellwig <hch@lst.de> [bwh: Backported to 3.2: as the iSeries code is still present, these functions have different names and live in rpa_vscsi.c.] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2014-08-06ibmvscsi: Abort init sequence during error recoveryBrian King
commit 9ee755974bea2f9880e517ec985dc9dede1b3a36 upstream. If a CRQ reset is triggered for some reason while in the middle of performing VSCSI adapter initialization, we don't want to call the done function for the initialization MAD commands as this will only result in two threads attempting initialization at the same time, resulting in failures. Signed-off-by: Brian King <brking@linux.vnet.ibm.com> Acked-by: Nathan Fontenot <nfont@linux.vnet.ibm.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2014-08-06xhci: Fix runtime suspended xhci from blocking system suspend.Wang, Yu
commit d6236f6d1d885aa19d1cd7317346fe795227a3cc upstream. The system suspend flow as following: 1, Freeze all user processes and kenrel threads. 2, Try to suspend all devices. 2.1, If pci device is in RPM suspended state, then pci driver will try to resume it to RPM active state in the prepare stage. 2.2, xhci_resume function calls usb_hcd_resume_root_hub to queue two workqueue items to resume usb2&usb3 roothub devices. 2.3, Call suspend callbacks of devices. 2.3.1, All suspend callbacks of all hcd's children, including roothub devices are called. 2.3.2, Finally, hcd_pci_suspend callback is called. Due to workqueue threads were already frozen in step 1, the workqueue items can't be scheduled, and the roothub devices can't be resumed in this flow. The HCD_FLAG_WAKEUP_PENDING flag which is set in usb_hcd_resume_root_hub won't be cleared. Finally, hcd_pci_suspend will return -EBUSY, and system suspend fails. The reason why this issue doesn't show up very often is due to that choose_wakeup will be called in step 2.3.1. In step 2.3.1, if udev->do_remote_wakeup is not equal to device_may_wakeup(&udev->dev), then udev will resume to RPM active for changing the wakeup settings. This has been a lucky hit which hides this issue. For some special xHCI controllers which have no USB2 port, then roothub will not match hub driver due to probe failed. Then its do_remote_wakeup will be set to zero, and we won't be as lucky. xhci driver doesn't need to resume roothub devices everytime like in the above case. It's only needed when there are pending event TRBs. This patch should be back-ported to kernels as old as 3.2, that contains the commit f69e3120df82391a0ee8118e0a156239a06b2afb "USB: XHCI: resume root hubs when the controller resumes" Signed-off-by: Wang, Yu <yu.y.wang@intel.com> Acked-by: Alan Stern <stern@rowland.harvard.edu> [use readl() instead of removed xhci_readl(), reword commit message -Mathias] Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2014-08-06xhci: clear root port wake on bits if controller isn't wake-up capableLu Baolu
commit ff8cbf250b448aac35589f6075082c3fcad8a8fe upstream. When xHCI PCI host is suspended, if do_wakeup is false in xhci_pci_suspend, xhci_bus_suspend needs to clear all root port wake on bits. Otherwise some Intel platforms may get a spurious wakeup, even if PCI PME# is disabled. This patch should be back-ported to kernels as old as 2.6.37, that contains the commit 9777e3ce907d4cb5a513902a87ecd03b52499569 "USB: xHCI: bus power management implementation". Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com> Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> [bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2014-08-06xhci: correct burst count field for isoc transfers on 1.0 xhci hostsMathias Nyman
commit 3213b151387df0b95f4eada104f68eb1c1409cb3 upstream. The transfer burst count (TBC) field in xhci 1.0 hosts should be set to the number of bursts needed to transfer all packets in a isoc TD. Supported values are 0-2 (1 to 3 bursts per service interval). Formula for TBC calculation is given in xhci spec section 4.11.2.3: TBC = roundup( Transfer Descriptor Packet Count / Max Burst Size +1 ) - 1 This patch should be applied to stable kernels since 3.0 that contain the commit 5cd43e33b9519143f06f507dd7cbee6b7a621885 "xhci 1.0: Set transfer burst count field." Suggested-by: ShiChun Ma <masc2008@qq.com> Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2014-08-06usb: option: add/modify Olivetti Olicard modemsBjørn Mork
commit b0ebef36e93703e59003ad6a1a20227e47714417 upstream. Adding a couple of Olivetti modems and blacklisting the net function on a couple which are already supported. Reported-by: Lars Melin <larsm17@gmail.com> Signed-off-by: Bjørn Mork <bjorn@mork.no> Signed-off-by: Johan Hovold <johan@kernel.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2014-08-06USB: ftdi_sio: fix null deref at port probeJohan Hovold
commit aea1ae8760314e072bf1b773521e9de5d5dda10d upstream. Fix NULL-pointer dereference when probing an interface with no endpoints. These devices have two bulk endpoints per interface, but this avoids crashing the kernel if a user forces a non-FTDI device to be probed. Note that the iterator variable was made unsigned in order to avoid a maybe-uninitialized compiler warning for ep_desc after the loop. Fixes: 895f28badce9 ("USB: ftdi_sio: fix hi-speed device packet size calculation") Reported-by: Mike Remski <mremski@mutualink.net> Tested-by: Mike Remski <mremski@mutualink.net> Signed-off-by: Johan Hovold <johan@kernel.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2014-08-06usb: gadget: f_fs: fix NULL pointer dereference when there are no stringsMichal Nazarewicz
commit f0688c8b81d2ea239c3fb0b848f623b579238d99 upstream. If the descriptors do not need any strings and user space sends empty set of strings, the ffs->stringtabs field remains NULL. Thus *ffs->stringtabs in functionfs_bind leads to a NULL pointer dereferenece. The bug was introduced by commit [fd7c9a007f: “use usb_string_ids_n()”]. While at it, remove double initialisation of lang local variable in that function. ffs->strings_count does not need to be checked in any way since in the above scenario it will remain zero and usb_string_ids_n() is a no-operation when colled with 0 argument. Signed-off-by: Michal Nazarewicz <mina86@mina86.com> Signed-off-by: Felipe Balbi <balbi@ti.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2014-07-11iommu/vt-d: Fix missing IOTLB flush in intel_iommu_unmap()David Woodhouse
Part of commit ea8ea460c9ace60bbb5ac6e5521d637d5c15293d upstream. This missing IOTLB flush was added as a minor, inconsequential bug-fix in commit ea8ea460c ("iommu/vt-d: Clean up and fix page table clear/free behaviour") in 3.15. It wasn't originally intended for -stable but a couple of users have reported issues which turn out to be fixed by adding the missing flush. Signed-off-by: David Woodhouse <David.Woodhouse@intel.com> [bwh: Backported to 3.2: - Adjust context - Use &dmar_domain->iommu_bmp, as it is a single word not an array] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2014-07-11megaraid: Use resource_size_t for PCI resources, not longBen Collins
commit 11f8a7b31f2140b0dc164bb484281235ffbe51d3 upstream. The assumption that sizeof(long) >= sizeof(resource_size_t) can lead to truncation of the PCI resource address, meaning this driver didn't work on 32-bit systems with 64-bit PCI adressing ranges. Signed-off-by: Ben Collins <ben.c@servergy.com> Acked-by: Sumit Saxena <sumit.saxena@lsi.com> Signed-off-by: James Bottomley <JBottomley@Parallels.com> [bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2014-07-11Fix spurious request sense in error handlingJames Bottomley
commit d555a2abf3481f81303d835046a5ec2c4fb3ca8e upstream. We unconditionally execute scsi_eh_get_sense() to make sure all failed commands that should have sense attached, do. However, the routine forgets that some commands, because of the way they fail, will not have any sense code ... we should not bother them with a REQUEST_SENSE command. Fix this by testing to see if we actually got a CHECK_CONDITION return and skip asking for sense if we don't. Tested-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: James Bottomley <JBottomley@Parallels.com> [bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2014-07-11target: Explicitly clear ramdisk_mcp backend pagesNicholas Bellinger
Part of commit 4442dc8a92b8f9ad8ee9e7f8438f4c04c03a22dc upstream. This patch changes rd_allocate_sgl_table() to explicitly clear ramdisk_mcp backend memory pages by passing __GFP_ZERO into alloc_pages(). This addresses a potential security issue where reading from a ramdisk_mcp could return sensitive information, and follows what >= v3.15 does to explicitly clear ramdisk_mcp memory at backend device initialization time. Reported-by: Jorge Daniel Sequeira Matias <jdsm@tecnico.ulisboa.pt> Cc: Jorge Daniel Sequeira Matias <jdsm@tecnico.ulisboa.pt> Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2014-07-11net/mlx4_core: Preserve pci_dev_data after __mlx4_remove_one()Wei Yang
[ Upstream commit befdf8978accecac2e0739e6b5075afc62db37fe ] This patch wrap up a helper function __mlx4_remove_one() which does the tear down function but preserve the drv_data. Functions like mlx4_pci_err_detected() and mlx4_restart_one() will call this one with out releasing drvdata. Signed-off-by: Wei Yang <weiyang@linux.vnet.ibm.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2014-07-11mlx4_core: Stash PCI ID driver_data in mlx4_priv structureWei Yang
[ No upstream commit, this is a cherry picked backport enabler. ] That way we can check flags later on, when we've finished with the pci_device_id structure. This is a backport. Signed-off-by: Roland Dreier <roland@purestorage.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2014-07-11dual scan thread bug fixJames Bottomley
commit f2495e228fce9f9cec84367547813cbb0d6db15a upstream. In the highly unusual case where two threads are running concurrently through the scanning code scanning the same target, we run into the situation where one may allocate the target while the other is still using it. In this case, because the reap checks for STARGET_CREATED and kills the target without reference counting, the second thread will do the wrong thing on reap. Fix this by reference counting even creates and doing the STARGET_CREATED check in the final put. Tested-by: Sarah Sharp <sarah.a.sharp@linux.intel.com> Signed-off-by: James Bottomley <JBottomley@Parallels.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2014-07-11fix our current target reap infrastructureJames Bottomley
commit e63ed0d7a98014fdfc2cfeb3f6dada313dcabb59 upstream. This patch eliminates the reap_ref and replaces it with a proper kref. On last put of this kref, the target is removed from visibility in sysfs. The final call to scsi_target_reap() for the device is done from __scsi_remove_device() and only if the device was made visible. This ensures that the target disappears as soon as the last device is gone rather than waiting until final release of the device (which is often too long). Reviewed-by: Alan Stern <stern@rowland.harvard.edu> Tested-by: Sarah Sharp <sarah.a.sharp@linux.intel.com> Signed-off-by: James Bottomley <JBottomley@Parallels.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2014-07-11Stop accepting SCSI requests before removing a deviceBart Van Assche
commit b485462aca7df4e32bcf7efb6f84a69e8b640243 upstream. Avoid that the code for requeueing SCSI requests triggers a crash by making sure that that code isn't scheduled anymore after a device has been removed. Also, source code inspection of __scsi_remove_device() revealed a race condition in this function: no new SCSI requests must be accepted for a SCSI device after device removal started. Signed-off-by: Bart Van Assche <bvanassche@acm.org> Reviewed-by: Mike Christie <michaelc@cs.wisc.edu> Acked-by: Tejun Heo <tj@kernel.org> Signed-off-by: James Bottomley <JBottomley@Parallels.com> [bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>