- 20 Jun, 2019 3 commits
-
-
Chaitanya Kulkarni authored
In function null_add_dev() struct nullb *nullb member is allocated using kzalloc_node() which returns 0red memory. In function setup_queues() which is called from the null_add_dev(), on successful queue allocation we set the nullb->nr_queues = 0 which is not needed due to earlier use of kzalloc_node(). Signed-off-by:
Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com> Signed-off-by:
Jens Axboe <axboe@kernel.dk>
-
Minwoo Im authored
__data_len and __sector are internal fields which should not be accessed directly in driver-level like the comment above it. But, tag field can be accessed by driver level directly so that we need to make the comment right by moving it to some other place. Cc: Jens Axboe <axboe@kernel.dk> Cc: linux-block@vger.kernel.org Signed-off-by:
Minwoo Im <minwoo.im.dev@gmail.com> Reviewed-by:
Christoph Hellwig <hch@lst.de> Signed-off-by:
-
Arnd Bergmann authored
clang warns about unusual code in floppy.c that looks like it was intended to be a bit mask operation, checking for a specific bit in the UDP->cmos variable (FLOPPY1_TYPE expands to '4' on ARM): drivers/block/floppy.c:3902:17: error: use of logical '&&' with constant operand [-Werror,-Wconstant-logical-operand] if (!UDP->cmos && FLOPPY1_TYPE) ^ ~~~~~~~~~~~~ drivers/block/floppy.c:3902:17: note: use '&' for a bitwise operation if (!UDP->cmos && FLOPPY1_TYPE) The check here is redundant anyway, if FLOPPY1_TYPE is zero, then assigning it to a zero UDP->cmos field does not change anything, so removing the extra check here has no effect other than shutting up the warning. On x86, this will no longer read a hardware register, as the FLOPPY1_TYPE macro is not expanded if UDP->cmos is already zero, but the result is the same. Cc: Robert Elliott <elliott@hpe.com> Cc: Keith Busch <kbusch@kernel.org> Link: https://patchwork.kernel.org/patch/10851841/Signed-off-by:Arnd Bergmann <arnd@arndb.de> Signed-off-by:
-
- 17 Jun, 2019 1 commit
-
-
Chaitanya Kulkarni authored
This is a pure code cleanup patch and doesn't change any functionality. In block layer to identify the request operation req_op() macro is used, so change the open coding the req_op() in the blk-mq-debugfs.c. Reviewed-by:
Martin K. Petersen <martin.petersen@oracle.com> Reviewed-by:
Hannes Reinecke <hare@suse.com> Signed-off-by:
-
- 15 Jun, 2019 20 commits
-
-
Tejun Heo authored
wbc_account_io() collects information on cgroup ownership of writeback pages to determine which cgroup should own the inode. Pages can stay associated with dead memcgs but we want to avoid attributing IOs to dead blkcgs as much as possible as the association is likely to be stale. However, currently, pages associated with dead memcgs contribute to the accounting delaying and/or confusing the arbitration. Fix it by ignoring pages associated with dead memcgs. Signed-off-by:
Tejun Heo <tj@kernel.org> Cc: Jan Kara <jack@suse.cz> Signed-off-by:
-
Tejun Heo authored
When blkcg_activate_policy() is creating blkg_policy_data for existing blkgs, it did in the wrong order - descendants first. Fix it. None of the existing controllers seem affected by this. Signed-off-by:
-
Tejun Heo authored
blkg alloc is performed as a separate step from the rest of blkg creation so that GFP_KERNEL allocations can be used when creating blkgs from configuration file writes because otherwise user actions may fail due to failures of opportunistic GFP_NOWAIT allocations. While making blkgs use percpu_ref, 7fcf2b03 ("blkcg: change blkg reference counting to use percpu_ref") incorrectly added unconditional opportunistic percpu_ref_init() to blkg_create() breaking this guarantee. This patch moves percpu_ref_init() to blkg_alloc() so makes it use @gfp_mask that blkg_alloc() is called with. Also, percpu_ref_exit() is moved to blkg_free() for consistency. Signed-off-by:
-
Tejun Heo authored
Depending on the number of devices, blkcg stats can go over the default seqfile buf size. seqfile normally retries with a larger buffer but since the ->pd_stat() addition, blkcg_print_stat() doesn't tell seqfile that overflow has happened and the output gets printed truncated. Fix it by calling seq_commit() w/ -1 on possible overflows. Signed-off-by:
-
Tejun Heo authored
If use_delay was non-zero when the latency target of a cgroup was set to zero, it will stay stuck until io.latency is enabled on the cgroup again. This keeps readahead disabled for the cgroup impacting performance negatively. Signed-off-by:
-
Gustavo A. R. Silva authored
One of the more common cases of allocation size calculations is finding the size of a structure that has a zero-sized array at the end, along with memory for some number of elements for that array. For example: struct bio_map_data { ... struct iovec iov[]; }; instance = kmalloc(sizeof(sizeof(struct bio_map_data) + sizeof(struct iovec) * count, GFP_KERNEL); Instead of leaving these open-coded and prone to type mistakes, we can now use the new struct_size() helper: instance = kmalloc(struct_size(instance, iov, count), GFP_KERNEL); This code was detected with the help of Coccinelle. Reviewed-by:Kees Cook <keescook@chromium.org> Signed-off-by:
Gustavo A. R. Silva <gustavo@embeddedor.com> Signed-off-by:
-
Gustavo A. R. Silva authored
Make use of the struct_size() helper instead of an open-coded version in order to avoid any potential type mistakes, in particular in the context in which this code is being used. So, replace the following form: sizeof(*new_ptbl) + target * sizeof(new_ptbl->part[0]) with: struct_size(new_ptbl, part, target) Also, notice that variable size is unnecessary, hence it is removed. This code was detected with the help of Coccinelle. Signed-off-by:
-
Bob Liu authored
Dulicate call of null_del_dev() will trigger null pointer error like below. The reason is a race condition between nullb_device_power_store() and nullb_group_drop_item(). CPU#0 CPU#1 ---------------- ----------------- do_rmdir() >configfs_rmdir() >client_drop_item() >nullb_group_drop_item() nullb_device_power_store() >null_del_dev() >test_and_clear_bit(NULLB_DEV_FL_UP >null_del_dev() ^^^^^ Duplicated null_dev_dev() triger null pointer error >clear_bit(NULLB_DEV_FL_UP The fix could be keep the sequnce of clear NULLB_DEV_FL_UP and null_del_dev(). [ 698.613600] BUG: unable to handle kernel NULL pointer dereference at 0000000000000018 [ 698.613608] #PF error: [normal kernel read fault] [ 698.613611] PGD 0 P4D 0 [ 698.613619] Oops: 0000 [#1] SMP PTI [ 698.613627] CPU: 3 PID: 6382 Comm: rmdir Not tainted 5.0.0+ #35 [ 698.613631] Hardware name: LENOVO 20LJS2EV08/20LJS2EV08, BIOS R0SET33W (1.17 ) 07/18/2018 [ 698.613644] RIP: 0010:null_del_dev+0xc/0x110 [null_blk] [ 698.613649] Code: 00 00 00 5b 41 5c 41 5d 41 5e 41 5f 5d c3 0f 0b eb 97 e8 47 bb 2a e8 0f 1f 80 00 00 00 00 0f 1f 44 00 00 55 48 89 e5 41 54 53 <8b> 77 18 48 89 fb 4c 8b 27 48 c7 c7 40 57 1e c1 e8 bf c7 cb e8 48 [ 698.613654] RSP: 0018:ffffb887888bfde0 EFLAGS: 00010286 [ 698.613659] RAX: 0000000000000000 RBX: ffff9d436d92bc00 RCX: ffff9d43a9184681 [ 698.613663] RDX: ffffffffc11e5c30 RSI: 0000000068be6540 RDI: 0000000000000000 [ 698.613667] RBP: ffffb887888bfdf0 R08: 0000000000000001 R09: 0000000000000000 [ 698.613671] R10: ffffb887888bfdd8 R11: 0000000000000f16 R12: ffff9d436d92bc08 [ 698.613675] R13: ffff9d436d94e630 R14: ffffffffc11e5088 R15: ffffffffc11e5000 [ 698.613680] FS: 00007faa68be6540(0000) GS:ffff9d43d14c0000(0000) knlGS:0000000000000000 [ 698.613685] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 698.613689] CR2: 0000000000000018 CR3: 000000042f70c002 CR4: 00000000003606e0 [ 698.613693] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 698.613697] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 698.613700] Call Trace: [ 698.613712] nullb_group_drop_item+0x50/0x70 [null_blk] [ 698.613722] client_drop_item+0x29/0x40 [ 698.613728] configfs_rmdir+0x1ed/0x300 [ 698.613738] vfs_rmdir+0xb2/0x130 [ 698.613743] do_rmdir+0x1c7/0x1e0 [ 698.613750] __x64_sys_rmdir+0x17/0x20 [ 698.613759] do_syscall_64+0x5a/0x110 [ 698.613768] entry_SYSCALL_64_after_hwframe+0x44/0xa9 Signed-off-by:Bob Liu <bob.liu@oracle.com> Signed-off-by:
-
Pavel Begunkov authored
struct blk_rq_stat::mean is a u64 value, so use %llu Signed-off-by:
Pavel Begunkov <asml.silence@gmail.com> Signed-off-by:
-
Guoqing Jiang authored
Andy reported that raid10 array with SSD disks has poor read performance. Compared with raid1, RAID-1 can be 3x faster than RAID-10 sometimes [1]. The thing is that raid10 chooses the low distance disk for read request, however, the approach doesn't work well for SSD device since it doesn't have spindle like HDD, we should just read from the SSD which has less pending IO like commit 9dedf603 ("md/raid1: read balance chooses idlest disk for SSD"). So this commit selects the idlest SSD disk for read if array has none rotational disk, otherwise, read_balance uses the previous distance priority algorithm. With the change, the performance of raid10 gets increased largely per Andy's test [2]. [1]. https://marc.info/?l=linux-raid&m=155915890004761&w=2 [2]. https://marc.info/?l=linux-raid&m=155990654223786&w=2Tested-by:
Andy Smith <andy@strugglers.net> Signed-off-by:
Guoqing Jiang <gqjiang@suse.com> Signed-off-by:
Song Liu <songliubraving@fb.com> Signed-off-by:
-
Marcos Paulo de Souza authored
Avoiding duplicated code, since they just execute a kfree. Signed-off-by:
Marcos Paulo de Souza <marcos.souza.org@gmail.com> Signed-off-by:
-
Gustavo A. R. Silva authored
One of the more common cases of allocation size calculations is finding the size of a structure that has a zero-sized array at the end, along with memory for some number of elements for that array. For example: struct foo { int stuff; struct boo entry[]; }; instance = kmalloc(size, GFP_KERNEL); Instead of leaving these open-coded and prone to type mistakes, we can now use the new struct_size() helper: instance = kmalloc(struct_size(instance, entry, count), GFP_KERNEL); This code was detected with the help of Coccinelle. Signed-off-by: -
Yufen Yu authored
This patch get rid of extra blank line and space, and add necessary space for code. Signed-off-by:
Yufen Yu <yuyufen@huawei.com> Signed-off-by:
-
Yufen Yu authored
This patch fix a spelling typo and add necessary space for code. In addition, the patch get rid of the unnecessary 'if'. Signed-off-by:
-
Marcos Paulo de Souza authored
Commit c42d3240 ("md: return -ENODEV if rdev has no mddev assigned") changed rdev_attr_store to return -ENODEV when rdev->mddev is NULL, now do the same to rdev_attr_show. Signed-off-by:
-
Xiao Ni authored
commit d5d885fd ("md: introduce new personality funciton start()") splits the init job to two parts. The first part run() does the jobs that do not require the md threads. The second part start() does the jobs that require the md threads. Now it just does run() in adding new journal device. It needs to do the second part start() too. Fixes: d5d885fd ("md: introduce new personality funciton start()") Cc: stable@vger.kernel.org #v4.9+ Reported-by:
Michal Soltys <soltys@ziu.info> Signed-off-by:
Xiao Ni <xni@redhat.com> Signed-off-by:
-
Marcos Paulo de Souza authored
These definitions are being moved to raid1-10.c. Signed-off-by:
-
git://git.kernel.dk/linux-blockLinus Torvalds authored
Pull block fixes from Jens Axboe: - Remove references to old schedulers for the scheduler switching and blkio controller documentation (Andreas) - Kill duplicate check for report zone for null_blk (Chaitanya) - Two bcache fixes (Coly) - Ensure that mq-deadline is selected if zoned block device is enabled, as we need that to support them (Damien) - Fix io_uring memory leak (Eric) - ps3vram fallout from LBDAF removal (Geert) - Redundant blk-mq debugfs debugfs_create return check cleanup (Greg) - Extend NOPLM quirk for ST1000LM024 drives (Hans) - Remove error path warning that can now trigger after the queue removal/addition fixes (Ming) * tag 'for-linus-20190614' of git://git.kernel.dk/linux-block: block/ps3vram: Use %llu to format sector_t after LBDAF removal libata: Extend quirks for the ST1000LM024 drives with NOLPM quirk bcache: only set BCACHE_DEV_WB_RUNNING when cached device attached bcache: fix stack corruption by PRECEDING_KEY() blk-mq: remove WARN_ON(!q->elevator) from blk_mq_sched_free_requests blkio-controller.txt: Remove references to CFQ block/switching-sched.txt: Update to blk-mq schedulers null_blk: remove duplicate check for report zone blk-mq: no need to check return value of debugfs_create functions io_uring: fix memory leak of UNIX domain socket inode block: force select mq-deadline for zoned block devices
-
git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linuxLinus Torvalds authored
Pull i2c fixes from Wolfram Sang: "I2C has two simple but wanted driver fixes for you" * 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux: i2c: pca-platform: Fix GPIO lookup code i2c: acorn: fix i2c warning
-
Casey Schaufler authored
The 5.1 mount system rework changed the smackfsdef mount option to smackfsdefault. This fixes the regression by making smackfsdef treated the same way as smackfsdefault. Also fix the smack_param_specs[] to have "smack" prefixes on all the names. This isn't visible to a user unless they either: (a) Try to mount a filesystem that's converted to the internal mount API and that implements the ->parse_monolithic() context operation - and only then if they call security_fs_context_parse_param() rather than security_sb_eat_lsm_opts(). There are no examples of this upstream yet, but nfs will probably want to do this for nfs2 or nfs3. (b) Use fsconfig() to configure the filesystem - in which case security_fs_context_parse_param() will be called. This issue is that smack_sb_eat_lsm_opts() checks for the "smack" prefix on the options, but smack_fs_context_parse_param() does not. Fixes: c3300aaf ("smack: get rid of match_token()") Fixes: 2febd254 ("smack: Implement filesystem context security hooks") Cc: stable@vger.kernel.org Reported-by:Jose Bollo <jose.bollo@iot.bzh> Signed-off-by:
Casey Schaufler <casey@schaufler-ca.com> Signed-off-by:
David Howells <dhowells@redhat.com> Tested-by:
Linus Torvalds <torvalds@linux-foundation.org>
-
- 14 Jun, 2019 16 commits
-
-
git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linuxLinus Torvalds authored
Pull arm64 fixes from Will Deacon: "Here are some arm64 fixes for -rc5. The only non-trivial change (in terms of the diffstat) is fixing our SVE ptrace API for big-endian machines, but the majority of this is actually the addition of much-needed comments and updates to the documentation to try to avoid this mess biting us again in future. There are still a couple of small things on the horizon, but nothing major at this point. Summary: - Fix broken SVE ptrace API when running in a big-endian configuration - Fix performance regression due to off-by-one in TLBI range checking - Fix build regression when using Clang" * tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: arm64/sve: Fix missing SVE/FPSIMD endianness conversions arm64: tlbflush: Ensure start/end of address range are aligned to stride arm64: Don't unconditionally add -Wno-psabi to KBUILD_CFLAGS
-
Linus Torvalds authored
Merge misc fixes from Andrew Morton: "16 fixes" * emailed patches from Andrew Morton <akpm@linux-foundation.org>: mm/devm_memremap_pages: fix final page put race PCI/P2PDMA: track pgmap references per resource, not globally lib/genalloc: introduce chunk owners PCI/P2PDMA: fix the gen_pool_add_virt() failure path mm/devm_memremap_pages: introduce devm_memunmap_pages drivers/base/devres: introduce devm_release_action() mm/vmscan.c: fix trying to reclaim unevictable LRU page coredump: fix race condition between collapse_huge_page() and core dumping mm/mlock.c: change count_mm_mlocked_page_nr return type mm: mmu_gather: remove __tlb_reset_range() for force flush fs/ocfs2: fix race in ocfs2_dentry_attach_lock() mm/vmscan.c: fix recent_rotated history mm/mlock.c: mlockall error for flag MCL_ONFAULT scripts/decode_stacktrace.sh: prefix addr2line with $CROSS_COMPILE mm/list_lru.c: fix memory leak in __memcg_init_list_lru_node mm: memcontrol: don't batch updates of local VM stats and events
-
git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommuLinus Torvalds authored
Pull iommu fixes from Joerg Roedel: - three fixes for Intel VT-d to fix a potential dead-lock, a formatting fix and a bit setting fix - one fix for the ARM-SMMU to make it work on some platforms with sub-optimal SMMU emulation * tag 'iommu-fixes-v5.2-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu: iommu/arm-smmu: Avoid constant zero in TLBI writes iommu/vt-d: Set the right field for Page Walk Snoop iommu/vt-d: Fix lock inversion between iommu->lock and device_domain_lock iommu: Add missing new line for dma type
-
git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpioLinus Torvalds authored
Pull GPIO fix from Linus Walleij: "A single fix for the PCA953x driver affecting some fringe variants of the chip" * tag 'gpio-v5.2-3' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio: gpio: pca953x: hack to fix 24 bit gpio expanders
-
git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/soundLinus Torvalds authored
Pull sound fixes from Takashi Iwai: "It might feel like deja vu to receive a bulk of changes at rc5, and it happens again; we've got a collection of fixes for ASoC. Most of fixes are targeted for the newly merged SOF (Sound Open Firmware) stuff and the relevant fixes for Intel platforms. Other than that, there are a few regression fixes for the recent ASoC core changes and HD-audio quirk, as well as a couple of FireWire fixes and for other ASoC codecs" * tag 'sound-5.2-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound: (54 commits) Revert "ALSA: hda/realtek - Improve the headset mic for Acer Aspire laptops" ALSA: ice1712: Check correct return value to snd_i2c_sendbytes (EWS/DMX 6Fire) ALSA: oxfw: allow PCM capture for Stanton SCS.1m ALSA: firewire-motu: fix destruction of data for isochronous resources ASoC: Intel: sst: fix kmalloc call with wrong flags ASoC: core: Fix deadlock in snd_soc_instantiate_card() SoC: rt274: Fix internal jack assignment in set_jack callback ALSA: hdac: fix memory release for SST and SOF drivers ASoC: SOF: Intel: hda: use the defined ppcap functions ASoC: core: move DAI pre-links initiation to snd_soc_instantiate_card ASoC: Intel: cht_bsw_rt5672: fix kernel oops with platform_name override ASoC: Intel: cht_bsw_nau8824: fix kernel oops with platform_name override ASoC: Intel: bytcht_es8316: fix kernel oops with platform_name override ASoC: Intel: cht_bsw_max98090: fix kernel oops with platform_name override ASoC: sun4i-i2s: Add offset to RX channel select ASoC: sun4i-i2s: Fix sun8i tx channel offset mask ASoC: max98090: remove 24-bit format support if RJ is 0 ASoC: da7219: Fix build error without CONFIG_I2C ASoC: SOF: Intel: hda: Fix COMPILE_TEST build error ASoC: SOF: fix DSP oops definitions in FW ABI ...
-
Hui Wang authored
This reverts commit 9cb40eb1. This patch introduces noise and headphone playback issue after rebooting or suspending/resuming. Let us revert it. BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=203831 Fixes: 9cb40eb1 ("ALSA: hda/realtek - Improve the headset mic for Acer Aspire laptops") Cc: <stable@vger.kernel.org> Signed-off-by:
Hui Wang <hui.wang@canonical.com> Signed-off-by:
Takashi Iwai <tiwai@suse.de>
-
Dan Williams authored
Logan noticed that devm_memremap_pages_release() kills the percpu_ref drops all the page references that were acquired at init and then immediately proceeds to unplug, arch_remove_memory(), the backing pages for the pagemap. If for some reason device shutdown actually collides with a busy / elevated-ref-count page then arch_remove_memory() should be deferred until after that reference is dropped. As it stands the "wait for last page ref drop" happens *after* devm_memremap_pages_release() returns, which is obviously too late and can lead to crashes. Fix this situation by assigning the responsibility to wait for the percpu_ref to go idle to devm_memremap_pages() with a new ->cleanup() callback. Implement the new cleanup callback for all devm_memremap_pages() users: pmem, devdax, hmm, and p2pdma. Link: http://lkml.kernel.org/r/155727339156.292046.5432007428235387859.stgit@dwillia2-desk3.amr.corp.intel.com Fixes: 41e94a85 ("add devm_memremap_pages") Signed-off-by:
Dan Williams <dan.j.williams@intel.com> Reported-by:
Logan Gunthorpe <logang@deltatee.com> Reviewed-by:
Ira Weiny <ira.weiny@intel.com> Reviewed-by:
Andrew Morton <akpm@linux-foundation.org> Signed-off-by:
-
Dan Williams authored
In preparation for fixing a race between devm_memremap_pages_release() and the final put of a page from the device-page-map, allocate a percpu-ref per p2pdma resource mapping. Link: http://lkml.kernel.org/r/155727338646.292046.9922678317501435597.stgit@dwillia2-desk3.amr.corp.intel.comSigned-off-by:
-
Dan Williams authored
The p2pdma facility enables a provider to publish a pool of dma addresses for a consumer to allocate. A genpool is used internally by p2pdma to collect dma resources, 'chunks', to be handed out to consumers. Whenever a consumer allocates a resource it needs to pin the 'struct dev_pagemap' instance that backs the chunk selected by pci_alloc_p2pmem(). Currently that reference is taken globally on the entire provider device. That sets up a lifetime mismatch whereby the p2pdma core needs to maintain hacks to make sure the percpu_ref is not released twice. This lifetime mismatch also stands in the way of a fix to devm_memremap_pages() whereby devm_memremap_pages_release() must wait for the percpu_ref ->release() callback to complete before it can proceed to teardown pages. So, towards fixing this situation, introduce the ability to store a 'chunk owner' at gen_pool_add() time, and a facility to retrieve the owner at gen_pool_{alloc,free}() time. For p2pdma this will be used to store and recall individual dev_pagemap reference counter instances per-chunk. Link: http://lkml.kernel.org/r/155727338118.292046.13407378933221579644.stgit@dwillia2-desk3.amr.corp.intel.comSigned-off-by: -
Dan Williams authored
The pci_p2pdma_add_resource() implementation immediately frees the pgmap if gen_pool_add_virt() fails. However, that means that when @dev triggers a devres release devm_memremap_pages_release() will crash trying to access the freed @pgmap. Use the new devm_memunmap_pages() to manually free the mapping in the error path. Link: http://lkml.kernel.org/r/155727337603.292046.13101332703665246702.stgit@dwillia2-desk3.amr.corp.intel.comSigned-off-by:
Bjorn Helgaas <bhelgaas@google.com> Reviewed-by:
-
Dan Williams authored
Use the new devm_release_action() facility to allow devm_memremap_pages_release() to be manually triggered. Link: http://lkml.kernel.org/r/155727337088.292046.5774214552136776763.stgit@dwillia2-desk3.amr.corp.intel.comSigned-off-by:
-
Dan Williams authored
Patch series "mm/devm_memremap_pages: Fix page release race", v2. Logan audited the devm_memremap_pages() shutdown path and noticed that it was possible to proceed to arch_remove_memory() before all potential page references have been reaped. Introduce a new ->cleanup() callback to do the work of waiting for any straggling page references and then perform the percpu_ref_exit() in devm_memremap_pages_release() context. For p2pdma this involves some deeper reworks to reference count resources on a per-instance basis rather than a per pci-device basis. A modified genalloc api is introduced to convey a driver-private pointer through gen_pool_{alloc,free}() interfaces. Also, a devm_memunmap_pages() api is introduced since p2pdma does not auto-release resources on a setup failure. The dax and pmem changes pass the nvdimm unit tests, and the p2pdma changes should now pass testing with the pci_p2pdma_release() fix. Jrme, how does this look for HMM? This patch (of 6): The devm_add_action() facility allows a resource allocation routine to add custom devm semantics. One such user is devm_memremap_pages(). There is now a need to manually trigger devm_memremap_pages_release(). Introduce devm_release_action() so the release action can be triggered via a new devm_memunmap_pages() api in a follow-on change. Link: http://lkml.kernel.org/r/155727336530.292046.2926860263201336366.stgit@dwillia2-desk3.amr.corp.intel.comSigned-off-by: -
Minchan Kim authored
There was the below bug report from Wu Fangsuo. On the CMA allocation path, isolate_migratepages_range() could isolate unevictable LRU pages and reclaim_clean_page_from_list() can try to reclaim them if they are clean file-backed pages. page:ffffffbf02f33b40 count:86 mapcount:84 mapping:ffffffc08fa7a810 index:0x24 flags: 0x19040c(referenced|uptodate|arch_1|mappedtodisk|unevictable|mlocked) raw: 000000000019040c ffffffc08fa7a810 0000000000000024 0000005600000053 raw: ffffffc009b05b20 ffffffc009b05b20 0000000000000000 ffffffc09bf3ee80 page dumped because: VM_BUG_ON_PAGE(PageLRU(page) || PageUnevictable(page)) page->mem_cgroup:ffffffc09bf3ee80 ------------[ cut here ]------------ kernel BUG at /home/build/farmland/adroid9.0/kernel/linux/mm/vmscan.c:1350! Internal error: Oops - BUG: 0 [#1] PREEMPT SMP Modules linked in: CPU: 0 PID: 7125 Comm: syz-executor Tainted: G S 4.14.81 #3 Hardware name: ASR AQUILAC EVB (DT) task: ffffffc00a54cd00 task.stack: ffffffc009b00000 PC is at shrink_page_list+0x1998/0x3240 LR is at shrink_page_list+0x1998/0x3240 pc : [<ffffff90083a2158>] lr : [<ffffff90083a2158>] pstate: 60400045 sp : ffffffc009b05940 .. shrink_page_list+0x1998/0x3240 reclaim_clean_pages_from_list+0x3c0/0x4f0 alloc_contig_range+0x3bc/0x650 cma_alloc+0x214/0x668 ion_cma_allocate+0x98/0x1d8 ion_alloc+0x200/0x7e0 ion_ioctl+0x18c/0x378 do_vfs_ioctl+0x17c/0x1780 SyS_ioctl+0xac/0xc0 Wu found it's due to commit ad6b6704 ("mm: remove SWAP_MLOCK in ttu"). Before that, unevictable pages go to cull_mlocked so that we can't reach the VM_BUG_ON_PAGE line. To fix the issue, this patch filters out unevictable LRU pages from the reclaim_clean_pages_from_list in CMA. Link: http://lkml.kernel.org/r/20190524071114.74202-1-minchan@kernel.org Fixes: ad6b6704 ("mm: remove SWAP_MLOCK in ttu") Signed-off-by:Minchan Kim <minchan@kernel.org> Reported-by:
Wu Fangsuo <fangsuowu@asrmicro.com> Debugged-by:
Michal Hocko <mhocko@suse.com> Cc: Pankaj Suryawanshi <pankaj.suryawanshi@einfochips.com> Cc: <stable@vger.kernel.org> [4.12+] Signed-off-by:
-
Andrea Arcangeli authored
When fixing the race conditions between the coredump and the mmap_sem holders outside the context of the process, we focused on mmget_not_zero()/get_task_mm() callers in 04f5866e ("coredump: fix race condition between mmget_not_zero()/get_task_mm() and core dumping"), but those aren't the only cases where the mmap_sem can be taken outside of the context of the process as Michal Hocko noticed while backporting that commit to older -stable kernels. If mmgrab() is called in the context of the process, but then the mm_count reference is transferred outside the context of the process, that can also be a problem if the mmap_sem has to be taken for writing through that mm_count reference. khugepaged registration calls mmgrab() in the context of the process, but the mmap_sem for writing is taken later in the context of the khugepaged kernel thread. collapse_huge_page() after taking the mmap_sem for writing doesn't modify any vma, so it's not obvious that it could cause a problem to the coredump, but it happens to modify the pmd in a way that breaks an invariant that pmd_trans_huge_lock() relies upon. collapse_huge_page() needs the mmap_sem for writing just to block concurrent page faults that call pmd_trans_huge_lock(). Specifically the invariant that "!pmd_trans_huge()" cannot become a "pmd_trans_huge()" doesn't hold while collapse_huge_page() runs. The coredump will call __get_user_pages() without mmap_sem for reading, which eventually can invoke a lockless page fault which will need a functional pmd_trans_huge_lock(). So collapse_huge_page() needs to use mmget_still_valid() to check it's not running concurrently with the coredump... as long as the coredump can invoke page faults without holding the mmap_sem for reading. This has "Fixes: khugepaged" to facilitate backporting, but in my view it's more a bug in the coredump code that will eventually have to be rewritten to stop invoking page faults without the mmap_sem for reading. So the long term plan is still to drop all mmget_still_valid(). Link: http://lkml.kernel.org/r/20190607161558.32104-1-aarcange@redhat.com Fixes: ba76149f ("thp: khugepaged") Signed-off-by:
Andrea Arcangeli <aarcange@redhat.com> Reported-by:
Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Jann Horn <jannh@google.com> Cc: Hugh Dickins <hughd@google.com> Cc: Mike Rapoport <rppt@linux.vnet.ibm.com> Cc: Mike Kravetz <mike.kravetz@oracle.com> Cc: Peter Xu <peterx@redhat.com> Cc: Jason Gunthorpe <jgg@mellanox.com> Cc: <stable@vger.kernel.org> Signed-off-by:
-
swkhack authored
On a 64-bit machine the value of "vma->vm_end - vma->vm_start" may be negative when using 32 bit ints and the "count >> PAGE_SHIFT"'s result will be wrong. So change the local variable and return value to unsigned long to fix the problem. Link: http://lkml.kernel.org/r/20190513023701.83056-1-swkhack@gmail.com Fixes: 0cf2f6f6 ("mm: mlock: check against vma for actual mlock() size") Signed-off-by:
swkhack <swkhack@gmail.com> Acked-by:
-
Yang Shi authored
A few new fields were added to mmu_gather to make TLB flush smarter for huge page by telling what level of page table is changed. __tlb_reset_range() is used to reset all these page table state to unchanged, which is called by TLB flush for parallel mapping changes for the same range under non-exclusive lock (i.e. read mmap_sem). Before commit dd2283f2 ("mm: mmap: zap pages with read mmap_sem in munmap"), the syscalls (e.g. MADV_DONTNEED, MADV_FREE) which may update PTEs in parallel don't remove page tables. But, the forementioned commit may do munmap() under read mmap_sem and free page tables. This may result in program hang on aarch64 reported by Jan Stancek. The problem could be reproduced by his test program with slightly modified below. ---8<--- static int map_size = 4096; static int num_iter = 500; static long threads_total; static void *distant_area; void *map_write_unmap(void *ptr) { int *fd = ptr; unsigned char *map_address; int i, j = 0; for (i = 0; i < num_iter; i++) { map_address = mmap(distant_area, (size_t) map_size, PROT_WRITE | PROT_READ, MAP_SHARED | MAP_ANONYMOUS, -1, 0); if (map_address == MAP_FAILED) { perror("mmap"); exit(1); } for (j = 0; j < map_size; j++) map_address[j] = 'b'; if (munmap(map_address, map_size) == -1) { perror("munmap"); exit(1); } } return NULL; } void *dummy(void *ptr) { return NULL; } int main(void) { pthread_t thid[2]; /* hint for mmap in map_write_unmap() */ distant_area = mmap(0, DISTANT_MMAP_SIZE, PROT_WRITE | PROT_READ, MAP_ANONYMOUS | MAP_PRIVATE, -1, 0); munmap(distant_area, (size_t)DISTANT_MMAP_SIZE); distant_area += DISTANT_MMAP_SIZE / 2; while (1) { pthread_create(&thid[0], NULL, map_write_unmap, NULL); pthread_create(&thid[1], NULL, dummy, NULL); pthread_join(thid[0], NULL); pthread_join(thid[1], NULL); } } ---8<--- The program may bring in parallel execution like below: t1 t2 munmap(map_address) downgrade_write(&mm->mmap_sem); unmap_region() tlb_gather_mmu() inc_tlb_flush_pending(tlb->mm); free_pgtables() tlb->freed_tables = 1 tlb->cleared_pmds = 1 pthread_exit() madvise(thread_stack, 8M, MADV_DONTNEED) zap_page_range() tlb_gather_mmu() inc_tlb_flush_pending(tlb->mm); tlb_finish_mmu() if (mm_tlb_flush_nested(tlb->mm)) __tlb_reset_range() __tlb_reset_range() would reset freed_tables and cleared_* bits, but this may cause inconsistency for munmap() which do free page tables. Then it may result in some architectures, e.g. aarch64, may not flush TLB completely as expected to have stale TLB entries remained. Use fullmm flush since it yields much better performance on aarch64 and non-fullmm doesn't yields significant difference on x86. The original proposed fix came from Jan Stancek who mainly debugged this issue, I just wrapped up everything together. Jan's testing results: v5.2-rc2-24-gbec7550c -------------------------- mean stddev real 37.382 2.780 user 1.420 0.078 sys 54.658 1.855 v5.2-rc2-24-gbec7550c + "mm: mmu_gather: remove __tlb_reset_range() for force flush" ---------------------------------------------------------------------------------------_ mean stddev real 37.119 2.105 user 1.548 0.087 sys 55.698 1.357 [akpm@linux-foundation.org: coding-style fixes] Link: http://lkml.kernel.org/r/1558322252-113575-1-git-send-email-yang.shi@linux.alibaba.com Fixes: dd2283f2 ("mm: mmap: zap pages with read mmap_sem in munmap") Signed-off-by:
Yang Shi <yang.shi@linux.alibaba.com> Signed-off-by:
Jan Stancek <jstancek@redhat.com> Reported-by:
Will Deacon <will.deacon@arm.com> Tested-by:
-
