- 12 Jan, 2015 1 commit
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Thomas Petazzoni authored
commit e5535545 upstream. Enabling the hardware I/O coherency on Armada 370, Armada 375, Armada 38x and Armada XP requires a certain number of conditions: - On Armada 370, the cache policy must be set to write-allocate. - On Armada 375, 38x and XP, the cache policy must be set to write-allocate, the pages must be mapped with the shareable attribute, and the SMP bit must be set Currently, on Armada XP, when CONFIG_SMP is enabled, those conditions are met. However, when Armada XP is used in a !CONFIG_SMP kernel, none of these conditions are met. With Armada 370, the situation is worse: since the processor is single core, regardless of whether CONFIG_SMP or !CONFIG_SMP is used, the cache policy will be set to write-back by the kernel and not write-allocate. Since solving this problem turns out to be quite complicated, and we don't want to let users with a mainline kernel known to have infrequent but existing data corruptions, this commit proposes to simply disable hardware I/O coherency in situations where it is known not to work. And basically, the is_smp() function of the kernel tells us whether it is OK to enable hardware I/O coherency or not, so this commit slightly refactors the coherency_type() function to return COHERENCY_FABRIC_TYPE_NONE when is_smp() is false, or the appropriate type of the coherency fabric in the other case. Thanks to this, the I/O coherency fabric will no longer be used at all in !CONFIG_SMP configurations. It will continue to be used in CONFIG_SMP configurations on Armada XP, Armada 375 and Armada 38x (which are multiple cores processors), but will no longer be used on Armada 370 (which is a single core processor). In the process, it simplifies the implementation of the coherency_type() function, and adds a missing call to of_node_put(). Signed-off-by:
Thomas Petazzoni <thomas.petazzoni@free-electrons.com> Fixes: e60304f8 ("arm: mvebu: Add hardware I/O Coherency support") Acked-by:
Gregory CLEMENT <gregory.clement@free-electrons.com> Link: https://lkml.kernel.org/r/1415871540-20302-3-git-send-email-thomas.petazzoni@free-electrons.comSigned-off-by:
Jason Cooper <jason@lakedaemon.net> Signed-off-by:
Luis Henriques <luis.henriques@canonical.com>
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- 05 Jan, 2015 39 commits
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Josef Bacik authored
commit a2804695 upstream. We use the modified list to keep track of which extents have been modified so we know which ones are candidates for logging at fsync() time. Newly modified extents are added to the list at modification time, around the same time the ordered extent is created. We do this so that we don't have to wait for ordered extents to complete before we know what we need to log. The problem is when something like this happens log extent 0-4k on inode 1 copy csum for 0-4k from ordered extent into log sync log commit transaction log some other extent on inode 1 ordered extent for 0-4k completes and adds itself onto modified list again log changed extents see ordered extent for 0-4k has already been logged at this point we assume the csum has been copied sync log crash On replay we will see the extent 0-4k in the log, drop the original 0-4k extent which is the same one that we are replaying which also drops the csum, and then we won't find the csum in the log for that bytenr. This of course causes us to have errors about not having csums for certain ranges of our inode. So remove the modified list manipulation in unpin_extent_cache, any modified extents should have been added well before now, and we don't want them re-logged. This fixes my test that I could reliably reproduce this problem with. Thanks, Signed-off-by:
Josef Bacik <jbacik@fb.com> Signed-off-by:
Chris Mason <clm@fb.com> Signed-off-by:
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Josef Bacik authored
commit 50d9aa99 upstream. Liu Bo pointed out that my previous fix would lose the generation update in the scenario I described. It is actually much worse than that, we could lose the entire extent if we lose power right after the transaction commits. Consider the following write extent 0-4k log extent in log tree commit transaction < power fail happens here ordered extent completes We would lose the 0-4k extent because it hasn't updated the actual fs tree, and the transaction commit will reset the log so it isn't replayed. If we lose power before the transaction commit we are save, otherwise we are not. Fix this by keeping track of all extents we logged in this transaction. Then when we go to commit the transaction make sure we wait for all of those ordered extents to complete before proceeding. This will make sure that if we lose power after the transaction commit we still have our data. This also fixes the problem of the improperly updated extent generation. Thanks, Signed-off-by:
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Josef Bacik authored
commit 9dba8cf1 upstream. If we have two fsync()'s race on different subvols one will do all of its work to get into the log_tree, wait on it's outstanding IO, and then allow the log_tree to finish it's commit. The problem is we were just free'ing that subvols logged extents instead of waiting on them, so whoever lost the race wouldn't really have their data on disk. Fix this by waiting properly instead of freeing the logged extents. Thanks, Signed-off-by:
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Ronald Wahl authored
commit b2ba27a5 upstream. Commit 76280832 (usb: gadget: at91_udc: prepare clk before calling enable) added clock preparation in interrupt context. This is not allowed as it might sleep. Also setting the clock rate is unsafe to call from there for the same reason. Move clock preparation and setting clock rate into process context (at91udc_probe). Signed-off-by:
Ronald Wahl <ronald.wahl@raritan.com> Acked-by:
Alexandre Belloni <alexandre.belloni@free-electrons.com> Acked-by:
Boris Brezillon <boris.brezillon@free-electrons.com> Acked-by:
Nicolas Ferre <nicolas.ferre@atmel.com> Cc: Felipe Balbi <balbi@ti.com> Signed-off-by:
Felipe Balbi <balbi@ti.com> Signed-off-by:
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Alex Deucher authored
commit 4bb62c95 upstream. Always need to set bit 0 of RLC_CGTT_MGCG_OVERRIDE to avoid unreliable doorbell updates in some cases. Signed-off-by:
Alex Deucher <alexander.deucher@amd.com> Signed-off-by:
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Lars-Peter Clausen authored
commit 50c0f21b upstream. Make sure to check the version field of the firmware header to make sure to not accidentally try to parse a firmware file with a different layout. Trying to do so can result in loading invalid firmware code to the device. Signed-off-by:
Lars-Peter Clausen <lars@metafoo.de> Signed-off-by:
Mark Brown <broonie@kernel.org> Signed-off-by:
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Tetsuo Handa authored
commit 881fdaa5 upstream. Andrew Morton wrote: > On Wed, 12 Nov 2014 13:08:55 +0900 Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp> wrote: > > > Andrew Morton wrote: > > > Poor ttm guys - this is a bit of a trap we set for them. > > > > Commit a91576d7 ("drm/ttm: Pass GFP flags in order to avoid deadlock.") > > changed to use sc->gfp_mask rather than GFP_KERNEL. > > > > - pages_to_free = kmalloc(npages_to_free * sizeof(struct page *), > > - GFP_KERNEL); > > + pages_to_free = kmalloc(npages_to_free * sizeof(struct page *), gfp); > > > > But this bug is caused by sc->gfp_mask containing some flags which are not > > in GFP_KERNEL, right? Then, I think > > > > - pages_to_free = kmalloc(npages_to_free * sizeof(struct page *), gfp); > > + pages_to_free = kmalloc(npages_to_free * sizeof(struct page *), gfp & GFP_KERNEL); > > > > would hide this bug. > > > > But I think we should use GFP_ATOMIC (or drop __GFP_WAIT flag) > > Well no - ttm_page_pool_free() should stop calling kmalloc altogether. > Just do > > struct page *pages_to_free[16]; > > and rework the code to free 16 pages at a time. Easy. Well, ttm code wants to process 512 pages at a time for performance. Memory footprint increased by 512 * sizeof(struct page *) buffer is only 4096 bytes. What about using static buffer like below? ---------- >From d3cb5393c9c8099d6b37e769f78c31af1541fe8c Mon Sep 17 00:00:00 2001 From: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Date: Thu, 13 Nov 2014 22:21:54 +0900 Subject: [PATCH] drm/ttm: Avoid memory allocation from shrinker functions. Commit a91576d7 ("drm/ttm: Pass GFP flags in order to avoid deadlock.") caused BUG_ON() due to sc->gfp_mask containing flags which are not in GFP_KERNEL. https://bugzilla.kernel.org/show_bug.cgi?id=87891 Changing from sc->gfp_mask to (sc->gfp_mask & GFP_KERNEL) would avoid the BUG_ON(), but avoiding memory allocation from shrinker function is better and reliable fix. Shrinker function is already serialized by global lock, and clean up function is called after shrinker function is unregistered. Thus, we can use static buffer when called from shrinker function and clean up function. Signed-off-by:
Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Signed-off-by:
Dave Airlie <airlied@redhat.com> Signed-off-by:
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Steven Rostedt (Red Hat) authored
commit 9960efeb upstream. When CONFIG_FRAME_POINTERS are enabled, it is required that the ftrace_caller and ftrace_regs_caller trampolines set up frame pointers otherwise a stack trace from a function call wont print the functions that called the trampoline. This is due to a check in __save_stack_address(): #ifdef CONFIG_FRAME_POINTER if (!reliable) return; #endif The "reliable" variable is only set if the function address is equal to contents of the address before the address the frame pointer register points to. If the frame pointer is not set up for the ftrace caller then this will fail the reliable test. It will miss the function that called the trampoline. Worse yet, if fentry is used (gcc 4.6 and beyond), it will also miss the parent, as the fentry is called before the stack frame is set up. That means the bp frame pointer points to the stack of just before the parent function was called. Link: http://lkml.kernel.org/r/20141119034829.355440340@goodmis.org Cc: Ingo Molnar <mingo@redhat.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: x86@kernel.org Acked-by:
Thomas Gleixner <tglx@linutronix.de> Signed-off-by:
Steven Rostedt <rostedt@goodmis.org> Signed-off-by:
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Jens Axboe authored
commit 5fabcb4c upstream. We can get here from blkdev_ioctl() -> blkpg_ioctl() -> add_partition() with a user passed in partno value. If we pass in 0x7fffffff, the new target in disk_expand_part_tbl() overflows the 'int' and we access beyond the end of ptbl->part[] and even write to it when we do the rcu_assign_pointer() to assign the new partition. Reported-by:
David Ramos <daramos@stanford.edu> Signed-off-by:
Jens Axboe <axboe@fb.com> Signed-off-by:
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Mikulas Patocka authored
commit 08d4f772 upstream. This patch fixes kmemcheck warning in switch_names. The function switch_names swaps inline names of two dentries. It swaps full arrays d_iname, no matter how many bytes are really used by the strings. Reading data beyond string ends results in kmemcheck warning. We fix the bug by marking both arrays as fully initialized. Signed-off-by:
Mikulas Patocka <mpatocka@redhat.com> Signed-off-by:
Al Viro <viro@zeniv.linux.org.uk> [ luis: backported to 3.16: adjusted context ] Signed-off-by:
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Oliver Neukum authored
commit a32c99e7 upstream. The touchscreen needs the same quirk as the other models. Signed-off-by:
Oliver Neukum <oneukum@suse.de> Reported-by:
Bryan Poling <poli0048@umn.edu> Acked-by:
Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by:
Jiri Kosina <jkosina@suse.cz> Signed-off-by:
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Adel Gadllah authored
commit fa51ee10 upstream. Yet another device that needs this quirk. Reported-by:
Tanguy de Baritault <tdebaritault@gmail.com> Signed-off-by:
Adel Gadllah <adel.gadllah@gmail.com> Signed-off-by:
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Martin Hauke authored
commit e7181d00 upstream. Added new device layout "DEVICE_HWI" and also added the USB VID/PID for the HP lt4112 LTE/HSPA+ Gobi 4G Modem (Huawei me906e) Signed-off-by:
Martin Hauke <mardnh@gmx.de> Signed-off-by:
Johan Hovold <johan@kernel.org> Signed-off-by:
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Catalin Marinas authored
commit 7d57511d upstream. Commit a469abd0 (ARM: elf: add new hwcap for identifying atomic ldrd/strd instructions) introduces HWCAP_ELF for 32-bit ARM applications. As LPAE is always present on arm64, report the corresponding compat HWCAP to user space. Signed-off-by:
Catalin Marinas <catalin.marinas@arm.com> Signed-off-by:
Will Deacon <will.deacon@arm.com> Signed-off-by:
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Dmitry Osipenko authored
commit e4a68009 upstream. Commit d127e9c5 ("ARM: tegra: make tegra_resume can work with current and later chips") removed tegra_get_soc_id macro leaving used cpu register corrupted after branching to v7_invalidate_l1() and as result causing execution of unintended code on tegra20. Possibly it was expected that r6 would be SoC id func argument since common cpu reset handler is setting r6 before branching to tegra_resume(), but neither tegra20_lp1_reset() nor tegra30_lp1_reset() aren't setting r6 register before jumping to resume function. Fix it by re-adding macro. Fixes: d127e9c5 (ARM: tegra: make tegra_resume can work with current and later chips) Reviewed-by:
Dmitry Osipenko <digetx@gmail.com> Signed-off-by:
Thierry Reding <treding@nvidia.com> Signed-off-by:
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Alex Deucher authored
commit 129acb7c upstream. Need to disable DS, not enable it when disabling dpm. Signed-off-by:
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Hannes Reinecke authored
commit b6c92b7e upstream. The .eh_abort_handler needs to return SUCCESS, FAILED, or FAST_IO_FAIL. So fixup all callers to adhere to this requirement. Reviewed-by:
Robert Elliott <elliott@hp.com> Signed-off-by:
Hannes Reinecke <hare@suse.de> Signed-off-by:
Christoph Hellwig <hch@lst.de> Signed-off-by:
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Myron Stowe authored
commit 36e81648 upstream. Commit 6ac665c6 ("PCI: rewrite PCI BAR reading code") masked off low-order bits from 'l', but not from 'sz'. Both are passed to pci_size(), which compares 'base == maxbase' to check for read-only BARs. The masking of 'l' means that comparison will never be 'true', so the check for read-only BARs no longer works. Resolve this by also masking off the low-order bits of 'sz' before passing it into pci_size() as 'maxbase'. With this change, pci_size() will once again catch the problems that have been encountered to date: - AGP aperture BAR of AMD-7xx host bridges: if the AGP window is disabled, this BAR is read-only and read as 0x00000008 [1] - BARs 0-4 of ALi IDE controllers can be non-zero and read-only [1] - Intel Sandy Bridge - Thermal Management Controller [8086:0103]; BAR 0 returning 0xfed98004 [2] - Intel Xeon E5 v3/Core i7 Power Control Unit [8086:2fc0]; Bar 0 returning 0x00001a [3] Link: [1] https://git.kernel.org/cgit/linux/kernel/git/tglx/history.git/commit/drivers/pci/probe.c?id=1307ef6621991f1c4bc3cec1b5a4ebd6fd3d66b9 ("PCI: probing read-only BARs" (pre-git)) Link: [2] https://bugzilla.kernel.org/show_bug.cgi?id=43331 Link: [3] https://bugzilla.kernel.org/show_bug.cgi?id=85991Reported-by:
William Unruh <unruh@physics.ubc.ca> Reported-by:
Martin Lucina <martin@lucina.net> Signed-off-by:
Myron Stowe <myron.stowe@redhat.com> Signed-off-by:
Bjorn Helgaas <bhelgaas@google.com> CC: Matthew Wilcox <willy@linux.intel.com> Signed-off-by:
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Lars Ellenberg authored
commit 3b9d35d7 upstream. This was not noticed for many years. Affects operation if md raid is used a backing device for DRBD. Signed-off-by:
Philipp Reisner <philipp.reisner@linbit.com> Signed-off-by:
Lars Ellenberg <lars.ellenberg@linbit.com> Signed-off-by:
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Alex Williamson authored
commit 0372ffb3 upstream. bus_find_device_by_name() acquires a device reference which is never released. This results in an object leak, which on older kernels results in failure to release all resources of PCI devices. libvirt uses drivers_probe to re-attach devices to the host after assignment and is therefore a common trigger for this leak. Example: # cd /sys/bus/pci/ # dmesg -C # echo 1 > devices/0000\:01\:00.0/sriov_numvfs # echo 0 > devices/0000\:01\:00.0/sriov_numvfs # dmesg | grep 01:10 pci 0000:01:10.0: [8086:10ca] type 00 class 0x020000 kobject: '0000:01:10.0' (ffff8801d79cd0a8): kobject_add_internal: parent: '0000:00:01.0', set: 'devices' kobject: '0000:01:10.0' (ffff8801d79cd0a8): kobject_uevent_env kobject: '0000:01:10.0' (ffff8801d79cd0a8): fill_kobj_path: path = '/devices/pci0000:00/0000:00:01.0/0000:01:10.0' kobject: '0000:01:10.0' (ffff8801d79cd0a8): kobject_uevent_env kobject: '0000:01:10.0' (ffff8801d79cd0a8): fill_kobj_path: path = '/devices/pci0000:00/0000:00:01.0/0000:01:10.0' kobject: '0000:01:10.0' (ffff8801d79cd0a8): kobject_uevent_env kobject: '0000:01:10.0' (ffff8801d79cd0a8): fill_kobj_path: path = '/devices/pci0000:00/0000:00:01.0/0000:01:10.0' kobject: '0000:01:10.0' (ffff8801d79cd0a8): kobject_cleanup, parent (null) kobject: '0000:01:10.0' (ffff8801d79cd0a8): calling ktype release kobject: '0000:01:10.0': free name [kobject freed as expected] # dmesg -C # echo 1 > devices/0000\:01\:00.0/sriov_numvfs # echo 0000:01:10.0 > drivers_probe # echo 0 > devices/0000\:01\:00.0/sriov_numvfs # dmesg | grep 01:10 pci 0000:01:10.0: [8086:10ca] type 00 class 0x020000 kobject: '0000:01:10.0' (ffff8801d79ce0a8): kobject_add_internal: parent: '0000:00:01.0', set: 'devices' kobject: '0000:01:10.0' (ffff8801d79ce0a8): kobject_uevent_env kobject: '0000:01:10.0' (ffff8801d79ce0a8): fill_kobj_path: path = '/devices/pci0000:00/0000:00:01.0/0000:01:10.0' kobject: '0000:01:10.0' (ffff8801d79ce0a8): kobject_uevent_env kobject: '0000:01:10.0' (ffff8801d79ce0a8): fill_kobj_path: path = '/devices/pci0000:00/0000:00:01.0/0000:01:10.0' kobject: '0000:01:10.0' (ffff8801d79ce0a8): kobject_uevent_env kobject: '0000:01:10.0' (ffff8801d79ce0a8): fill_kobj_path: path = '/devices/pci0000:00/0000:00:01.0/0000:01:10.0' [no free] Signed-off-by:
Alex Williamson <alex.williamson@redhat.com> Signed-off-by:
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Ian Abbott authored
commit cf35d6e0 upstream. `genwqe_user_vmap()` calls `get_user_pages_fast()` and if the return value is less than the number of pages requested, it frees the pages and returns an error (`-EFAULT`). However, it fails to consider a negative error return value from `get_user_pages_fast()`. In that case, the test `if (rc < m->nr_pages)` will be false (due to promotion of `rc` to a large `unsigned int`) and the code will continue on to call `genwqe_map_pages()` with an invalid list of page pointers. Fix it by bailing out if `get_user_pages_fast()` returns a negative error value. Signed-off-by:
Ian Abbott <abbotti@mev.co.uk> Signed-off-by:
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Vitaly Kuznetsov authored
commit 04a258c1 upstream. When build with Debug the following crash is sometimes observed: Call Trace: [<ffffffff812b9600>] string+0x40/0x100 [<ffffffff812bb038>] vsnprintf+0x218/0x5e0 [<ffffffff810baf7d>] ? trace_hardirqs_off+0xd/0x10 [<ffffffff812bb4c1>] vscnprintf+0x11/0x30 [<ffffffff8107a2f0>] vprintk+0xd0/0x5c0 [<ffffffffa0051ea0>] ? vmbus_process_rescind_offer+0x0/0x110 [hv_vmbus] [<ffffffff8155c71c>] printk+0x41/0x45 [<ffffffffa004ebac>] vmbus_device_unregister+0x2c/0x40 [hv_vmbus] [<ffffffffa0051ecb>] vmbus_process_rescind_offer+0x2b/0x110 [hv_vmbus] ... This happens due to the following race: between 'if (channel->device_obj)' check in vmbus_process_rescind_offer() and pr_debug() in vmbus_device_unregister() the device can disappear. Fix the issue by taking an additional reference to the device before proceeding to vmbus_device_unregister(). Signed-off-by:
Vitaly Kuznetsov <vkuznets@redhat.com> Signed-off-by:
K. Y. Srinivasan <kys@microsoft.com> Signed-off-by:
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Vitaly Kuznetsov authored
commit 31d4ea1a upstream. An attempt to fix fcopy on i586 (bc5a5b02 Drivers: hv: util: Properly pack the data for file copy functionality) led to a regression on x86_64 (and actually didn't fix i586 breakage). Fcopy messages from Hyper-V host come in the following format: struct do_fcopy_hdr | 36 bytes 0000 | 4 bytes offset | 8 bytes size | 4 bytes data | 6144 bytes On x86_64 struct hv_do_fcopy matched this format without ' __attribute__((packed))' and on i586 adding ' __attribute__((packed))' to it doesn't change anything. Keep the structure packed and add padding to match re reality. Tested both i586 and x86_64 on Hyper-V Server 2012 R2. Signed-off-by:
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Richard Weinberger authored
commit f38aed97 upstream. The logic of vfree()'ing vol->upd_buf is tied to vol->updating. In ubi_start_update() vol->updating is set long before vmalloc()'ing vol->upd_buf. If we encounter a write failure in ubi_start_update() before vmalloc() the UBI device release function will try to vfree() vol->upd_buf because vol->updating is set. Fix this by allocating vol->upd_buf directly after setting vol->updating. Fixes: [ 31.559338] UBI warning: vol_cdev_release: update of volume 2 not finished, volume is damaged [ 31.559340] ------------[ cut here ]------------ [ 31.559343] WARNING: CPU: 1 PID: 2747 at mm/vmalloc.c:1446 __vunmap+0xe3/0x110() [ 31.559344] Trying to vfree() nonexistent vm area (ffffc90001f2b000) [ 31.559345] Modules linked in: [ 31.565620] 0000000000000bba ffff88002a0cbdb0 ffffffff818f0497 ffff88003b9ba148 [ 31.566347] ffff88002a0cbde0 ffffffff8156f515 ffff88003b9ba148 0000000000000bba [ 31.567073] 0000000000000000 0000000000000000 ffff88002a0cbe88 ffffffff8156c10a [ 31.567793] Call Trace: [ 31.568034] [<ffffffff818f0497>] dump_stack+0x4e/0x7a [ 31.568510] [<ffffffff8156f515>] ubi_io_write_vid_hdr+0x155/0x160 [ 31.569084] [<ffffffff8156c10a>] ubi_eba_write_leb+0x23a/0x870 [ 31.569628] [<ffffffff81569b36>] vol_cdev_write+0x226/0x380 [ 31.570155] [<ffffffff81179265>] vfs_write+0xb5/0x1f0 [ 31.570627] [<ffffffff81179f8a>] SyS_pwrite64+0x6a/0xa0 [ 31.571123] [<ffffffff818fde12>] system_call_fastpath+0x16/0x1b Signed-off-by:
Richard Weinberger <richard@nod.at> Signed-off-by:
Artem Bityutskiy <artem.bityutskiy@linux.intel.com> Signed-off-by:
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Richard Weinberger authored
commit aa5ad3b6 upstream. If the erase worker is unable to erase a PEB it will free the ubi_wl_entry itself. The failing ubi_wl_entry must not free()'d again after do_sync_erase() returns. Signed-off-by:
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Christian Borntraeger authored
commit 2dca485f upstream. some control register changes will flush some aspects of the CPU, e.g. POP explicitely mentions that for CR9-CR11 "TLBs may be cleared". Instead of trying to be clever and only flush on specific CRs, let play safe and flush on all lctl(g) as future machines might define new bits in CRs. Load control intercept should not happen that often. Signed-off-by:
Christian Borntraeger <borntraeger@de.ibm.com> Acked-by:
Cornelia Huck <cornelia.huck@de.ibm.com> Reviewed-by:
David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by:
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Christian Borntraeger authored
commit 1365039d upstream. ipte_unlock_siif uses cmpxchg to replace the in-memory data of the ipte lock together with ACCESS_ONCE for the intial read. union ipte_control { unsigned long val; struct { unsigned long k : 1; unsigned long kh : 31; unsigned long kg : 32; }; }; [...] static void ipte_unlock_siif(struct kvm_vcpu *vcpu) { union ipte_control old, new, *ic; ic = &vcpu->kvm->arch.sca->ipte_control; do { new = old = ACCESS_ONCE(*ic); new.kh--; if (!new.kh) new.k = 0; } while (cmpxchg(&ic->val, old.val, new.val) != old.val); if (!new.kh) wake_up(&vcpu->kvm->arch.ipte_wq); } The new value, is loaded twice from memory with gcc 4.7.2 of fedora 18, despite the ACCESS_ONCE: ---> l %r4,0(%r3) <--- load first 32 bit of lock (k and kh) in r4 alfi %r4,2147483647 <--- add -1 to r4 llgtr %r4,%r4 <--- zero out the sign bit of r4 lg %r1,0(%r3) <--- load all 64 bit of lock into new lgr %r2,%r1 <--- load the same into old risbg %r1,%r4,1,31,32 <--- shift and insert r4 into the bits 1-31 of new llihf %r4,2147483647 ngrk %r4,%r1,%r4 jne aa0 <ipte_unlock+0xf8> nihh %r1,32767 lgr %r4,%r2 csg %r4,%r1,0(%r3) cgr %r2,%r4 jne a70 <ipte_unlock+0xc8> If the memory value changes between the first load (l) and the second load (lg) we are broken. If that happens VCPU threads will hang (unkillable) in handle_ipte_interlock. Andreas Krebbel analyzed this and tracked it down to a compiler bug in that version: "while it is not that obvious the C99 standard basically forbids duplicating the memory access also in that case. For an argumentation of a similiar case please see: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=22278#c43 For the implementation-defined cases regarding volatile there are some GCC-specific clarifications which can be found here: https://gcc.gnu.org/onlinedocs/gcc/Volatiles.html#Volatiles I've tracked down the problem with a reduced testcase. The problem was that during a tree level optimization (SRA - scalar replacement of aggregates) the volatile marker is lost. And an RTL level optimizer (CSE - common subexpression elimination) then propagated the memory read into its second use introducing another access to the memory location. So indeed Christian's suspicion that the union access has something to do with it is correct (since it triggered the SRA optimization). This issue has been reported and fixed in the GCC 4.8 development cycle: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=58145" This patch replaces the ACCESS_ONCE scheme with a barrier() based scheme that should work for all supported compilers. Signed-off-by:
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Kazuya Mizuguchi authored
commit 11432050 upstream. This patch fixes an issue that the NULL pointer dereference happens when we uses g_audio driver. Since the g_audio driver will call usb_ep_disable() in afunc_set_alt() before it calls usb_ep_enable(), the uep->pipe of renesas usbhs driver will be NULL. So, this patch adds a condition to avoid the oops. Signed-off-by:
Kazuya Mizuguchi <kazuya.mizuguchi.ks@renesas.com> Signed-off-by:
Takeshi Kihara <takeshi.kihara.df@renesas.com> Signed-off-by:
Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com> Fixes: 2f98382d (usb: renesas_usbhs: Add Renesas USBHS Gadget) Signed-off-by:
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Tejun Heo authored
commit 9c6ac78e upstream. After invoking ->dirty_inode(), __mark_inode_dirty() does smp_mb() and tests inode->i_state locklessly to see whether it already has all the necessary I_DIRTY bits set. The comment above the barrier doesn't contain any useful information - memory barriers can't ensure "changes are seen by all cpus" by itself. And it sure enough was broken. Please consider the following scenario. CPU 0 CPU 1 ------------------------------------------------------------------------------- enters __writeback_single_inode() grabs inode->i_lock tests PAGECACHE_TAG_DIRTY which is clear enters __set_page_dirty() grabs mapping->tree_lock sets PAGECACHE_TAG_DIRTY releases mapping->tree_lock leaves __set_page_dirty() enters __mark_inode_dirty() smp_mb() sees I_DIRTY_PAGES set leaves __mark_inode_dirty() clears I_DIRTY_PAGES releases inode->i_lock Now @inode has dirty pages w/ I_DIRTY_PAGES clear. This doesn't seem to lead to an immediately critical problem because requeue_inode() later checks PAGECACHE_TAG_DIRTY instead of I_DIRTY_PAGES when deciding whether the inode needs to be requeued for IO and there are enough unintentional memory barriers inbetween, so while the inode ends up with inconsistent I_DIRTY_PAGES flag, it doesn't fall off the IO list. The lack of explicit barrier may also theoretically affect the other I_DIRTY bits which deal with metadata dirtiness. There is no guarantee that a strong enough barrier exists between I_DIRTY_[DATA]SYNC clearing and write_inode() writing out the dirtied inode. Filesystem inode writeout path likely has enough stuff which can behave as full barrier but it's theoretically possible that the writeout may not see all the updates from ->dirty_inode(). Fix it by adding an explicit smp_mb() after I_DIRTY clearing. Note that I_DIRTY_PAGES needs a special treatment as it always needs to be cleared to be interlocked with the lockless test on __mark_inode_dirty() side. It's cleared unconditionally and reinstated after smp_mb() if the mapping still has dirty pages. Also add comments explaining how and why the barriers are paired. Lightly tested. Signed-off-by:
Tejun Heo <tj@kernel.org> Cc: Jan Kara <jack@suse.cz> Cc: Mikulas Patocka <mpatocka@redhat.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: Al Viro <viro@zeniv.linux.org.uk> Reviewed-by:
Jan Kara <jack@suse.cz> Signed-off-by:
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Frank Schaefer authored
commit 22799487 upstream. This patches fixes an ancient bug in the dvb_usb_af9005 driver, which has been reported at least in the following threads: https://lkml.org/lkml/2009/2/4/350 https://lkml.org/lkml/2014/9/18/558 If the driver is compiled in without any IR support (neither DVB_USB_AF9005_REMOTE nor custom symbols), the symbol_request calls in af9005_usb_module_init() return pointers != NULL although the IR symbols are not available. This leads to the following oops: ... [ 8.529751] usbcore: registered new interface driver dvb_usb_af9005 [ 8.531584] BUG: unable to handle kernel paging request at 02e00000 [ 8.533385] IP: [<7d9d67c6>] af9005_usb_module_init+0x6b/0x9d [ 8.535613] *pde = 00000000 [ 8.536416] Oops: 0000 [#1] PREEMPT PREEMPT DEBUG_PAGEALLOCDEBUG_PAGEALLOC [ 8.537863] CPU: 0 PID: 1 Comm: swapper Not tainted 3.15.0-rc6-00151-ga5c075cf #1 [ 8.539827] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.7.5-20140531_083030-gandalf 04/01/2014 [ 8.541519] task: 89c9a670 ti: 89c9c000 task.ti: 89c9c000 [ 8.541519] EIP: 0060:[<7d9d67c6>] EFLAGS: 00010206 CPU: 0 [ 8.541519] EIP is at af9005_usb_module_init+0x6b/0x9d [ 8.541519] EAX: 02e00000 EBX: 00000000 ECX: 00000006 EDX: 00000000 [ 8.541519] ESI: 00000000 EDI: 7da33ec8 EBP: 89c9df30 ESP: 89c9df2c [ 8.541519] DS: 007b ES: 007b FS: 0000 GS: 00e0 SS: 0068 [ 8.541519] CR0: 8005003b CR2: 02e00000 CR3: 05a54000 CR4: 00000690 [ 8.541519] Stack: [ 8.541519] 7d9d675b 89c9df90 7d992a49 7d7d5914 89c9df4c 7be3a800 7d08c58c 8a4c3968 [ 8.541519] 89c9df80 7be3a966 00000192 00000006 00000006 7d7d3ff4 8a4c397a 00000200 [ 8.541519] 7d6b1280 8a4c3979 00000006 000009a6 7da32db8 b13eec81 00000006 000009a6 [ 8.541519] Call Trace: [ 8.541519] [<7d9d675b>] ? ttusb2_driver_init+0x16/0x16 [ 8.541519] [<7d992a49>] do_one_initcall+0x77/0x106 [ 8.541519] [<7be3a800>] ? parameqn+0x2/0x35 [ 8.541519] [<7be3a966>] ? parse_args+0x113/0x25c [ 8.541519] [<7d992bc2>] kernel_init_freeable+0xea/0x167 [ 8.541519] [<7cf01070>] kernel_init+0x8/0xb8 [ 8.541519] [<7cf27ec0>] ret_from_kernel_thread+0x20/0x30 [ 8.541519] [<7cf01068>] ? rest_init+0x10c/0x10c [ 8.541519] Code: 08 c2 c7 05 44 ed f9 7d 00 00 e0 02 c7 05 40 ed f9 7d 00 00 e0 02 c7 05 3c ed f9 7d 00 00 e0 02 75 1f b8 00 00 e0 02 85 c0 74 16 <a1> 00 00 e0 02 c7 05 54 84 8e 7d 00 00 e0 02 a3 58 84 8e 7d eb [ 8.541519] EIP: [<7d9d67c6>] af9005_usb_module_init+0x6b/0x9d SS:ESP 0068:89c9df2c [ 8.541519] CR2: 0000000002e00000 [ 8.541519] ---[ end trace 768b6faf51370fc7 ]--- The prefered fix would be to convert the whole IR code to use the kernel IR infrastructure (which wasn't available at the time this driver had been created). Until anyone who still has this old hardware steps up an does the conversion, fix it by not calling the symbol_request calls if the driver is compiled in without the default IR symbols (CONFIG_DVB_USB_AF9005_REMOTE). Due to the IR related pointers beeing NULL by default, IR support will then be disabled. The downside of this solution is, that it will no longer be possible to compile custom IR symbols (not using CONFIG_DVB_USB_AF9005_REMOTE) in. Please note that this patch has NOT been tested with all possible cases. I don't have the hardware and could only verify that it fixes the reported bug. Reported-by:
Fengguag Wu <fengguang.wu@intel.com> Signed-off-by:
Frank Schäfer <fschaefer.oss@googlemail.com> Acked-by:
Luca Olivetti <luca@ventoso.org> Signed-off-by:
Mauro Carvalho Chehab <mchehab@osg.samsung.com> Signed-off-by:
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Mauro Carvalho Chehab authored
commit 678fa12f upstream. The au0828 quirks table is currently not in sync with the au0828 media driver. Syncronize it and put them on the same order as found at au0828 driver, as all the au0828 devices with analog TV need the same quirks. Signed-off-by:
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Mauro Carvalho Chehab authored
commit 5d1f00a2 upstream. Add a macro to simplify au0828 quirk table. That makes easier to check it against the USB IDs at drivers/media/usb/au0828/au0828-cards.c. Signed-off-by:
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Johan Hedberg authored
commit 980ffc0a upstream. The le_conn_timeout() may call hci_le_conn_failed() which in turn may call hci_conn_del(). Trying to use the _sync variant for cancelling the conn timeout from hci_conn_del() could therefore result in a deadlock. This patch converts hci_conn_del() to use the non-sync variant so the deadlock is not possible. Signed-off-by:
Johan Hedberg <johan.hedberg@intel.com> Signed-off-by:
Marcel Holtmann <marcel@holtmann.org> Signed-off-by:
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Sakari Ailus authored
commit bc47150a upstream. The PLL flags were not used correctly. Signed-off-by:
Sakari Ailus <sakari.ailus@linux.intel.com> Acked-by:
Laurent Pinchart <laurent.pinchart@ideasonboard.com> Signed-off-by:
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Sakari Ailus authored
commit f85698cd upstream. The mutex does not serialise anything in this case but avoids a lockdep warning from the control framework. Signed-off-by:
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Thomas Huth authored
commit a36c5393 upstream. The monitor-class number field is only 16 bits, so we have to use a u16 pointer to access it. Signed-off-by:
Thomas Huth <thuth@linux.vnet.ibm.com> Reviewed-by:
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Markus Pargmann authored
commit fe08be3e upstream. The code reads the default voltage selector from its register. If the bootloader disables the regulator, the default voltage selector will be 0 which results in faulty behaviour of this regulator driver. This patch sets a default voltage selector for vddpu if it is not set in the register. Signed-off-by:
Markus Pargmann <mpa@pengutronix.de> Signed-off-by:
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Mark Fasheh authored
commit 0b4699dc upstream. btrfs_drop_snapshot() leaves subvolume qgroup items on disk after completion. This can cause problems with snapshot creation. If a new snapshot tries to claim the deleted subvolumes id, btrfs will get -EEXIST from add_qgroup_item() and go read-only. The following commands will reproduce this problem (assume btrfs is on /dev/sda and is mounted at /btrfs) mkfs.btrfs -f /dev/sda mount -t btrfs /dev/sda /btrfs/ btrfs quota enable /btrfs/ btrfs su sna /btrfs/ /btrfs/snap btrfs su de /btrfs/snap sleep 45 umount /btrfs/ mount -t btrfs /dev/sda /btrfs/ We can fix this by catching -EEXIST in add_qgroup_item() and initializing the existing items. We have the problem of orphaned relation items being on disk from an old snapshot but that is outside the scope of this patch. Signed-off-by:
Mark Fasheh <mfasheh@suse.de> Signed-off-by:
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Martin Schwidefsky authored
commit e512d56c upstream. git commit 37f81fa1 "n_tty: do O_ONLCR translation as a single write" surfaced a bug in the 3215 device driver. In combination this broke tab expansion for tty ouput. The cause is an asymmetry in the behaviour of tty3215_ops->write vs tty3215_ops->put_char. The put_char function scans for '\t' but the write function does not. As the driver has logic for the '\t' expansion remove XTABS from c_oflag of the initial termios as well. Reported-by:
Stephen Powell <zlinuxman@wowway.com> Signed-off-by:
Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Ben Hutchings <ben@decadent.org.uk> Signed-off-by:
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