December 2024 - Linux-stable-mirror

[PATCH 5.4] perf/x86/intel/pt: Fix buffer full but size is 0 case

by Adrian Hunter

commit 5b590160d2cf776b304eb054afafea2bd55e3620 upstream. If the trace data buffer becomes full, a truncated flag [T] is reported in PERF_RECORD_AUX. In some cases, the size reported is 0, even though data must have been added to make the buffer full. That happens when the buffer fills up from empty to full before the Intel PT driver has updated the buffer position. Then the driver calculates the new buffer position before calculating the data size. If the old and new positions are the same, the data size is reported as 0, even though it is really the whole buffer size. Fix by detecting when the buffer position is wrapped, and adjust the data size calculation accordingly. Example Use a very small buffer size (8K) and observe the size of truncated [T] data. Before the fix, it is possible to see records of 0 size. Before: $ perf record -m,8K -e intel_pt// uname Linux [ perf record: Woken up 2 times to write data ] [ perf record: Captured and wrote 0.105 MB perf.data ] $ perf script -D --no-itrace | grep AUX | grep -F '[T]' Warning: AUX data lost 2 times out of 3! 5 19462712368111 0x19710 [0x40]: PERF_RECORD_AUX offset: 0 size: 0 flags: 0x1 [T] 5 19462712700046 0x19ba8 [0x40]: PERF_RECORD_AUX offset: 0x170 size: 0xe90 flags: 0x1 [T] After: $ perf record -m,8K -e intel_pt// uname Linux [ perf record: Woken up 3 times to write data ] [ perf record: Captured and wrote 0.040 MB perf.data ] $ perf script -D --no-itrace | grep AUX | grep -F '[T]' Warning: AUX data lost 2 times out of 3! 1 113720802995 0x4948 [0x40]: PERF_RECORD_AUX offset: 0 size: 0x2000 flags: 0x1 [T] 1 113720979812 0x6b10 [0x40]: PERF_RECORD_AUX offset: 0x2000 size: 0x2000 flags: 0x1 [T] Fixes: 52ca9ced3f70 ("perf/x86/intel/pt: Add Intel PT PMU driver") Signed-off-by: Adrian Hunter <adrian.hunter(a)intel.com> Signed-off-by: Peter Zijlstra (Intel) <peterz(a)infradead.org> Cc: stable(a)vger.kernel.org Link: https://lkml.kernel.org/r/20241022155920.17511-2-adrian.hunter@intel.com Signed-off-by: Adrian Hunter <adrian.hunter(a)intel.com> --- arch/x86/events/intel/pt.c | 11 ++++++++--- arch/x86/events/intel/pt.h | 2 ++ 2 files changed, 10 insertions(+), 3 deletions(-) diff --git a/arch/x86/events/intel/pt.c b/arch/x86/events/intel/pt.c index 99b286b6c200..622bfb9a2fe7 100644 --- a/arch/x86/events/intel/pt.c +++ b/arch/x86/events/intel/pt.c @@ -782,11 +782,13 @@ static void pt_buffer_advance(struct pt_buffer *buf) buf->cur_idx++; if (buf->cur_idx == buf->cur->last) { - if (buf->cur == buf->last) + if (buf->cur == buf->last) { buf->cur = buf->first; - else + buf->wrapped = true; + } else { buf->cur = list_entry(buf->cur->list.next, struct topa, list); + } buf->cur_idx = 0; } } @@ -800,8 +802,11 @@ static void pt_buffer_advance(struct pt_buffer *buf) static void pt_update_head(struct pt *pt) { struct pt_buffer *buf = perf_get_aux(&pt->handle); + bool wrapped = buf->wrapped; u64 topa_idx, base, old; + buf->wrapped = false; + /* offset of the first region in this table from the beginning of buf */ base = buf->cur->offset + buf->output_off; @@ -814,7 +819,7 @@ static void pt_update_head(struct pt *pt) } else { old = (local64_xchg(&buf->head, base) & ((buf->nr_pages << PAGE_SHIFT) - 1)); - if (base < old) + if (base < old || (base == old && wrapped)) base += buf->nr_pages << PAGE_SHIFT; local_add(base - old, &buf->data_size); diff --git a/arch/x86/events/intel/pt.h b/arch/x86/events/intel/pt.h index c2d00a072952..51674454c69d 100644 --- a/arch/x86/events/intel/pt.h +++ b/arch/x86/events/intel/pt.h @@ -64,6 +64,7 @@ struct pt_pmu { * @lost: if data was lost/truncated * @head: logical write offset inside the buffer * @snapshot: if this is for a snapshot/overwrite counter + * @wrapped: buffer advance wrapped back to the first topa table * @stop_pos: STOP topa entry index * @intr_pos: INT topa entry index * @stop_te: STOP topa entry pointer @@ -80,6 +81,7 @@ struct pt_buffer { local_t data_size; local64_t head; bool snapshot; + bool wrapped; long stop_pos, intr_pos; struct topa_entry *stop_te, *intr_te; void **data_pages; -- 2.43.0

8 months, 3 weeks

2
1
0 0

[PATCH] selinux: ignore unknown extended permissions

by Thiébaud Weksteen

When evaluating extended permissions, ignore unknown permissions instead of calling BUG(). This commit ensures that future permissions can be added without interfering with older kernels. Fixes: fa1aa143ac4a ("selinux: extended permissions for ioctls") Cc: stable(a)vger.kernel.org Signed-off-by: Thiébaud Weksteen <tweek(a)google.com> --- security/selinux/ss/services.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/security/selinux/ss/services.c b/security/selinux/ss/services.c index 971c45d576ba..2fa8aebcb2e5 100644 --- a/security/selinux/ss/services.c +++ b/security/selinux/ss/services.c @@ -979,7 +979,8 @@ void services_compute_xperms_decision(struct extended_perms_decision *xpermd, return; break; default: - BUG(); + // An unknown extended permission has been found. Ignore it. + return; } if (node->key.specified == AVTAB_XPERMS_ALLOWED) { -- 2.47.0.338.g60cca15819-goog

8 months, 3 weeks

2
1
0 0

[PATCH] drm/xe: Wait for migration job before unmapping pages

by Nirmoy Das

There could be still migration job going on while doing xe_tt_unmap_sg() which could trigger GPU page faults. Fix this by waiting for the migration job to finish. Closes: https://gitlab.freedesktop.org/drm/xe/kernel/-/issues/3466 Fixes: 75521e8b56e8 ("drm/xe: Perform dma_map when moving system buffer objects to TT") Cc: Thomas Hellström <thomas.hellstrom(a)linux.intel.com> Cc: Matthew Brost <matthew.brost(a)intel.com> Cc: Lucas De Marchi <lucas.demarchi(a)intel.com> Cc: <stable(a)vger.kernel.org> # v6.11+ Signed-off-by: Nirmoy Das <nirmoy.das(a)intel.com> --- drivers/gpu/drm/xe/xe_bo.c | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/xe/xe_bo.c b/drivers/gpu/drm/xe/xe_bo.c index 73689dd7d672..40c5c74e9306 100644 --- a/drivers/gpu/drm/xe/xe_bo.c +++ b/drivers/gpu/drm/xe/xe_bo.c @@ -857,8 +857,16 @@ static int xe_bo_move(struct ttm_buffer_object *ttm_bo, bool evict, out: if ((!ttm_bo->resource || ttm_bo->resource->mem_type == XE_PL_SYSTEM) && - ttm_bo->ttm) + ttm_bo->ttm) { + long timeout = dma_resv_wait_timeout(ttm_bo->base.resv, + DMA_RESV_USAGE_BOOKKEEP, + true, + MAX_SCHEDULE_TIMEOUT); + if (timeout < 0) + ret = timeout; + xe_tt_unmap_sg(ttm_bo->ttm); + } return ret; } -- 2.46.0

8 months, 3 weeks

1
0
0 0

+ zram-fix-uninitialized-zram-not-releasing-backing-device.patch added to mm-hotfixes-unstable branch

by Andrew Morton

The patch titled Subject: zram: fix uninitialized ZRAM not releasing backing device has been added to the -mm mm-hotfixes-unstable branch. Its filename is zram-fix-uninitialized-zram-not-releasing-backing-device.patch This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patche… This patch will later appear in the mm-hotfixes-unstable branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/process/submit-checklist.rst when testing your code *** The -mm tree is included into linux-next via the mm-everything branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm and is updated there every 2-3 working days ------------------------------------------------------ From: Kairui Song <kasong(a)tencent.com> Subject: zram: fix uninitialized ZRAM not releasing backing device Date: Thu, 5 Dec 2024 02:02:24 +0800 Setting backing device is done before ZRAM initialization. If we set the backing device, then remove the ZRAM module without initializing the device, the backing device reference will be leaked and the device will be hold forever. Fix this by always check and release the backing device when resetting or removing ZRAM. Link: https://lkml.kernel.org/r/20241204180224.31069-3-ryncsn@gmail.com Fixes: 013bf95a83ec ("zram: add interface to specif backing device") Signed-off-by: Kairui Song <kasong(a)tencent.com> Reported-by: Desheng Wu <deshengwu(a)tencent.com> Cc: Minchan Kim <minchan(a)kernel.org> Cc: Sergey Senozhatsky <senozhatsky(a)chromium.org> Cc: <stable(a)vger.kernel.org> Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org> --- drivers/block/zram/zram_drv.c | 3 +++ 1 file changed, 3 insertions(+) --- a/drivers/block/zram/zram_drv.c~zram-fix-uninitialized-zram-not-releasing-backing-device +++ a/drivers/block/zram/zram_drv.c @@ -2335,6 +2335,9 @@ static void zram_reset_device(struct zra zram->limit_pages = 0; if (!init_done(zram)) { + /* Backing device could be set before ZRAM initialization. */ + reset_bdev(zram); + up_write(&zram->init_lock); return; } _ Patches currently in -mm which might be from kasong(a)tencent.com are zram-refuse-to-use-zero-sized-block-device-as-backing-device.patch zram-fix-uninitialized-zram-not-releasing-backing-device.patch

8 months, 3 weeks

1
0
0 0

+ zram-refuse-to-use-zero-sized-block-device-as-backing-device.patch added to mm-hotfixes-unstable branch

by Andrew Morton

The patch titled Subject: zram: refuse to use zero sized block device as backing device has been added to the -mm mm-hotfixes-unstable branch. Its filename is zram-refuse-to-use-zero-sized-block-device-as-backing-device.patch This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patche… This patch will later appear in the mm-hotfixes-unstable branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/process/submit-checklist.rst when testing your code *** The -mm tree is included into linux-next via the mm-everything branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm and is updated there every 2-3 working days ------------------------------------------------------ From: Kairui Song <kasong(a)tencent.com> Subject: zram: refuse to use zero sized block device as backing device Date: Thu, 5 Dec 2024 02:02:23 +0800 Patch series "zram: fix backing device setup issue". This series fixes two bugs of backing device setting: - ZRAM should reject using a zero sized (or the uninitialized ZRAM device itself) as the backing device. - Fix backing device leaking when removing a uninitialized ZRAM device. This patch (of 2): Setting a zero sized block device as backing device is pointless, and one can easily create a recursive loop by setting the uninitialized ZRAM device itself as its own backing device by (zram0 is uninitialized): echo /dev/zram0 > /sys/block/zram0/backing_dev It's definitely a wrong config, and the module will pin itself, kernel should refuse doing so in the first place. By refusing to use zero sized device we avoided misuse cases including this one above. Link: https://lkml.kernel.org/r/20241204180224.31069-1-ryncsn@gmail.com Link: https://lkml.kernel.org/r/20241204180224.31069-2-ryncsn@gmail.com Fixes: 013bf95a83ec ("zram: add interface to specif backing device") Signed-off-by: Kairui Song <kasong(a)tencent.com> Reported-by: Desheng Wu <deshengwu(a)tencent.com> Cc: Minchan Kim <minchan(a)kernel.org> Cc: Sergey Senozhatsky <senozhatsky(a)chromium.org> Cc: <stable(a)vger.kernel.org> Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org> --- drivers/block/zram/zram_drv.c | 6 ++++++ 1 file changed, 6 insertions(+) --- a/drivers/block/zram/zram_drv.c~zram-refuse-to-use-zero-sized-block-device-as-backing-device +++ a/drivers/block/zram/zram_drv.c @@ -614,6 +614,12 @@ static ssize_t backing_dev_store(struct } nr_pages = i_size_read(inode) >> PAGE_SHIFT; + /* Refuse to use zero sized device (also prevents self reference) */ + if (!nr_pages) { + err = -EINVAL; + goto out; + } + bitmap_sz = BITS_TO_LONGS(nr_pages) * sizeof(long); bitmap = kvzalloc(bitmap_sz, GFP_KERNEL); if (!bitmap) { _ Patches currently in -mm which might be from kasong(a)tencent.com are zram-refuse-to-use-zero-sized-block-device-as-backing-device.patch zram-fix-uninitialized-zram-not-releasing-backing-device.patch

8 months, 3 weeks

1
0
0 0

[PATCH RESEND v2] drm/i915: Fix memory leak by correcting cache object name in error handler

by Jiasheng Jiang

From: Jiasheng Jiang <jiashengjiangcool(a)outlook.com> Replace "slab_priorities" with "slab_dependencies" in the error handler to avoid memory leak. Fixes: 32eb6bcfdda9 ("drm/i915: Make request allocation caches global") Cc: <stable(a)vger.kernel.org> # v5.2+ Reviewed-by: Nirmoy Das <nirmoy.das(a)intel.com> Signed-off-by: Jiasheng Jiang <jiashengjiangcool(a)outlook.com> --- Changelog: v1 -> v2: 1. Alter the subject. --- drivers/gpu/drm/i915/i915_scheduler.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/gpu/drm/i915/i915_scheduler.c b/drivers/gpu/drm/i915/i915_scheduler.c index 762127dd56c5..70a854557e6e 100644 --- a/drivers/gpu/drm/i915/i915_scheduler.c +++ b/drivers/gpu/drm/i915/i915_scheduler.c @@ -506,6 +506,6 @@ int __init i915_scheduler_module_init(void) return 0; err_priorities: - kmem_cache_destroy(slab_priorities); + kmem_cache_destroy(slab_dependencies); return -ENOMEM; } -- 2.25.1

8 months, 3 weeks

2
2
0 0

[tip: x86/urgent] x86/cpu: Add Lunar Lake to list of CPUs with a broken MONITOR implementation

by tip-bot2 for Len Brown

The following commit has been merged into the x86/urgent branch of tip: Commit-ID: c9a4b55431e5220347881e148725bed69c84e037 Gitweb: https://git.kernel.org/tip/c9a4b55431e5220347881e148725bed69c84e037 Author: Len Brown <len.brown(a)intel.com> AuthorDate: Tue, 12 Nov 2024 21:07:00 -05:00 Committer: Dave Hansen <dave.hansen(a)linux.intel.com> CommitterDate: Wed, 04 Dec 2024 12:30:14 -08:00 x86/cpu: Add Lunar Lake to list of CPUs with a broken MONITOR implementation Under some conditions, MONITOR wakeups on Lunar Lake processors can be lost, resulting in significant user-visible delays. Add Lunar Lake to X86_BUG_MONITOR so that wake_up_idle_cpu() always sends an IPI, avoiding this potential delay. Reported originally here: https://bugzilla.kernel.org/show_bug.cgi?id=219364 [ dhansen: tweak subject ] Signed-off-by: Len Brown <len.brown(a)intel.com> Signed-off-by: Dave Hansen <dave.hansen(a)linux.intel.com> Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki(a)intel.com> Cc:stable@vger.kernel.org Link: https://lore.kernel.org/all/a4aa8842a3c3bfdb7fe9807710eef159cbf0e705.173146… --- arch/x86/kernel/cpu/intel.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/arch/x86/kernel/cpu/intel.c b/arch/x86/kernel/cpu/intel.c index d1de300..8ded9f8 100644 --- a/arch/x86/kernel/cpu/intel.c +++ b/arch/x86/kernel/cpu/intel.c @@ -555,7 +555,9 @@ static void init_intel(struct cpuinfo_x86 *c) c->x86_vfm == INTEL_WESTMERE_EX)) set_cpu_bug(c, X86_BUG_CLFLUSH_MONITOR); - if (boot_cpu_has(X86_FEATURE_MWAIT) && c->x86_vfm == INTEL_ATOM_GOLDMONT) + if (boot_cpu_has(X86_FEATURE_MWAIT) && + (c->x86_vfm == INTEL_ATOM_GOLDMONT || + c->x86_vfm == INTEL_LUNARLAKE_M)) set_cpu_bug(c, X86_BUG_MONITOR); #ifdef CONFIG_X86_64

8 months, 3 weeks

1
0
0 0

[PATCH 0/3] fixes for udmabuf (memfd sealing checks and a leak)

by Jann Horn

I have tested that patches 2 and 3 work using the following reproducers. I did not write a reproducer for the issue described in patch 1. Reproducer for F_SEAL_FUTURE_WRITE not being respected: ``` #define _GNU_SOURCE #include <err.h> #include <fcntl.h> #include <stdio.h> #include <unistd.h> #include <sys/ioctl.h> #include <sys/mman.h> #include <linux/udmabuf.h> #define SYSCHK(x) ({ \ typeof(x) __res = (x); \ if (__res == (typeof(x))-1) \ err(1, "SYSCHK(" #x ")"); \ __res; \ }) int main(void) { int memfd = SYSCHK(memfd_create("test", MFD_ALLOW_SEALING)); SYSCHK(ftruncate(memfd, 0x1000)); SYSCHK(fcntl(memfd, F_ADD_SEALS, F_SEAL_SHRINK|F_SEAL_FUTURE_WRITE)); int udmabuf_fd = SYSCHK(open("/dev/udmabuf", O_RDWR)); struct udmabuf_create create_arg = { .memfd = memfd, .flags = 0, .offset = 0, .size = 0x1000 }; int buf_fd = SYSCHK(ioctl(udmabuf_fd, UDMABUF_CREATE, &create_arg)); printf("created udmabuf buffer fd %d\n", buf_fd); char *map = SYSCHK(mmap(NULL, 0x1000, PROT_READ|PROT_WRITE, MAP_SHARED, buf_fd, 0)); *map = 'a'; } ``` Reproducer for the memory leak (if you run this for a while, your memory usage will steadily go up, and /sys/kernel/debug/dma_buf/bufinfo will contain a ton of entries): ``` #define _GNU_SOURCE #include <err.h> #include <errno.h> #include <assert.h> #include <fcntl.h> #include <stdio.h> #include <unistd.h> #include <sys/ioctl.h> #include <sys/mman.h> #include <sys/resource.h> #include <linux/udmabuf.h> #define SYSCHK(x) ({ \ typeof(x) __res = (x); \ if (__res == (typeof(x))-1) \ err(1, "SYSCHK(" #x ")"); \ __res; \ }) int main(void) { int memfd = SYSCHK(memfd_create("test", MFD_ALLOW_SEALING)); SYSCHK(ftruncate(memfd, 0x1000)); SYSCHK(fcntl(memfd, F_ADD_SEALS, F_SEAL_SHRINK)); int udmabuf_fd = SYSCHK(open("/dev/udmabuf", O_RDWR)); // prevent creating new FDs struct rlimit rlim = { .rlim_cur = 1, .rlim_max = 1 }; SYSCHK(setrlimit(RLIMIT_NOFILE, &rlim)); while (1) { struct udmabuf_create create_arg = { .memfd = memfd, .flags = 0, .offset = 0, .size = 0x1000 }; int buf_fd = ioctl(udmabuf_fd, UDMABUF_CREATE, &create_arg); assert(buf_fd == -1); assert(errno == EMFILE); } } ``` Signed-off-by: Jann Horn <jannh(a)google.com> --- Jann Horn (3): udmabuf: fix racy memfd sealing check udmabuf: also check for F_SEAL_FUTURE_WRITE udmabuf: fix memory leak on last export_udmabuf() error path drivers/dma-buf/udmabuf.c | 36 ++++++++++++++++++++---------------- 1 file changed, 20 insertions(+), 16 deletions(-) --- base-commit: b86545e02e8c22fb89218f29d381fa8e8b91d815 change-id: 20241203-udmabuf-fixes-d0435ebab663 -- Jann Horn <jannh(a)google.com>

8 months, 3 weeks

2
5
0 0

[PATCH AUTOSEL 4.19] PCI: Add 'reset_subordinate' to reset hierarchy below bridge

by Sasha Levin

From: Keith Busch <kbusch(a)kernel.org> [ Upstream commit 2fa046449a82a7d0f6d9721dd83e348816038444 ] The "bus" and "cxl_bus" reset methods reset a device by asserting Secondary Bus Reset on the bridge leading to the device. These only work if the device is the only device below the bridge. Add a sysfs 'reset_subordinate' attribute on bridges that can assert Secondary Bus Reset regardless of how many devices are below the bridge. This resets all the devices below a bridge in a single command, including the locking and config space save/restore that reset methods normally do. This may be the only way to reset devices that don't support other reset methods (ACPI, FLR, PM reset, etc). Link: https://lore.kernel.org/r/20241025222755.3756162-1-kbusch@meta.com Signed-off-by: Keith Busch <kbusch(a)kernel.org> [bhelgaas: commit log, add capable(CAP_SYS_ADMIN) check] Signed-off-by: Bjorn Helgaas <bhelgaas(a)google.com> Reviewed-by: Alex Williamson <alex.williamson(a)redhat.com> Reviewed-by: Amey Narkhede <ameynarkhede03(a)gmail.com> Signed-off-by: Sasha Levin <sashal(a)kernel.org> --- Documentation/ABI/testing/sysfs-bus-pci | 11 +++++++++++ drivers/pci/pci-sysfs.c | 26 +++++++++++++++++++++++++ drivers/pci/pci.c | 2 +- drivers/pci/pci.h | 1 + 4 files changed, 39 insertions(+), 1 deletion(-) diff --git a/Documentation/ABI/testing/sysfs-bus-pci b/Documentation/ABI/testing/sysfs-bus-pci index 44d4b2be92fd4..c68d1d9a4d479 100644 --- a/Documentation/ABI/testing/sysfs-bus-pci +++ b/Documentation/ABI/testing/sysfs-bus-pci @@ -125,6 +125,17 @@ Description: will be present in sysfs. Writing 1 to this file will perform reset. +What: /sys/bus/pci/devices/.../reset_subordinate +Date: October 2024 +Contact: linux-pci(a)vger.kernel.org +Description: + This is visible only for bridge devices. If you want to reset + all devices attached through the subordinate bus of a specific + bridge device, writing 1 to this will try to do it. This will + affect all devices attached to the system through this bridge + similiar to writing 1 to their individual "reset" file, so use + with caution. + What: /sys/bus/pci/devices/.../vpd Date: February 2008 Contact: Ben Hutchings <bwh(a)kernel.org> diff --git a/drivers/pci/pci-sysfs.c b/drivers/pci/pci-sysfs.c index f68798763af8d..d5287dfac9171 100644 --- a/drivers/pci/pci-sysfs.c +++ b/drivers/pci/pci-sysfs.c @@ -507,6 +507,31 @@ static ssize_t dev_bus_rescan_store(struct device *dev, } static DEVICE_ATTR(rescan, (S_IWUSR|S_IWGRP), NULL, dev_bus_rescan_store); +static ssize_t reset_subordinate_store(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t count) +{ + struct pci_dev *pdev = to_pci_dev(dev); + struct pci_bus *bus = pdev->subordinate; + unsigned long val; + + if (!capable(CAP_SYS_ADMIN)) + return -EPERM; + + if (kstrtoul(buf, 0, &val) < 0) + return -EINVAL; + + if (val) { + int ret = __pci_reset_bus(bus); + + if (ret) + return ret; + } + + return count; +} +static DEVICE_ATTR_WO(reset_subordinate); + #if defined(CONFIG_PM) && defined(CONFIG_ACPI) static ssize_t d3cold_allowed_store(struct device *dev, struct device_attribute *attr, @@ -778,6 +803,7 @@ static struct attribute *pci_dev_attrs[] = { static struct attribute *pci_bridge_attrs[] = { &dev_attr_subordinate_bus_number.attr, &dev_attr_secondary_bus_number.attr, + &dev_attr_reset_subordinate.attr, NULL, }; diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index aa2be8d815048..e22040c8a0aec 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -5295,7 +5295,7 @@ EXPORT_SYMBOL_GPL(pci_probe_reset_bus); * * Same as above except return -EAGAIN if the bus cannot be locked */ -static int __pci_reset_bus(struct pci_bus *bus) +int __pci_reset_bus(struct pci_bus *bus) { int rc; diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h index 39725b71300f8..1db9b8ff6043d 100644 --- a/drivers/pci/pci.h +++ b/drivers/pci/pci.h @@ -36,6 +36,7 @@ int pci_mmap_fits(struct pci_dev *pdev, int resno, struct vm_area_struct *vmai, int pci_probe_reset_function(struct pci_dev *dev); int pci_bridge_secondary_bus_reset(struct pci_dev *dev); int pci_bus_error_reset(struct pci_dev *dev); +int __pci_reset_bus(struct pci_bus *bus); /** * struct pci_platform_pm_ops - Firmware PM callbacks -- 2.43.0

8 months, 3 weeks

1
0
0 0

[PATCH AUTOSEL 5.4 1/4] f2fs: fix f2fs_bug_on when uninstalling filesystem call f2fs_evict_inode.

by Sasha Levin

From: Qi Han <hanqi(a)vivo.com> [ Upstream commit d5c367ef8287fb4d235c46a2f8c8d68715f3a0ca ] creating a large files during checkpoint disable until it runs out of space and then delete it, then remount to enable checkpoint again, and then unmount the filesystem triggers the f2fs_bug_on as below: ------------[ cut here ]------------ kernel BUG at fs/f2fs/inode.c:896! CPU: 2 UID: 0 PID: 1286 Comm: umount Not tainted 6.11.0-rc7-dirty #360 Oops: invalid opcode: 0000 [#1] PREEMPT SMP NOPTI RIP: 0010:f2fs_evict_inode+0x58c/0x610 Call Trace: __die_body+0x15/0x60 die+0x33/0x50 do_trap+0x10a/0x120 f2fs_evict_inode+0x58c/0x610 do_error_trap+0x60/0x80 f2fs_evict_inode+0x58c/0x610 exc_invalid_op+0x53/0x60 f2fs_evict_inode+0x58c/0x610 asm_exc_invalid_op+0x16/0x20 f2fs_evict_inode+0x58c/0x610 evict+0x101/0x260 dispose_list+0x30/0x50 evict_inodes+0x140/0x190 generic_shutdown_super+0x2f/0x150 kill_block_super+0x11/0x40 kill_f2fs_super+0x7d/0x140 deactivate_locked_super+0x2a/0x70 cleanup_mnt+0xb3/0x140 task_work_run+0x61/0x90 The root cause is: creating large files during disable checkpoint period results in not enough free segments, so when writing back root inode will failed in f2fs_enable_checkpoint. When umount the file system after enabling checkpoint, the root inode is dirty in f2fs_evict_inode function, which triggers BUG_ON. The steps to reproduce are as follows: dd if=/dev/zero of=f2fs.img bs=1M count=55 mount f2fs.img f2fs_dir -o checkpoint=disable:10% dd if=/dev/zero of=big bs=1M count=50 sync rm big mount -o remount,checkpoint=enable f2fs_dir umount f2fs_dir Let's redirty inode when there is not free segments during checkpoint is disable. Signed-off-by: Qi Han <hanqi(a)vivo.com> Reviewed-by: Chao Yu <chao(a)kernel.org> Signed-off-by: Jaegeuk Kim <jaegeuk(a)kernel.org> Signed-off-by: Sasha Levin <sashal(a)kernel.org> --- fs/f2fs/inode.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/fs/f2fs/inode.c b/fs/f2fs/inode.c index 53e1a757e4e17..b0cbb01df8cba 100644 --- a/fs/f2fs/inode.c +++ b/fs/f2fs/inode.c @@ -631,8 +631,10 @@ int f2fs_write_inode(struct inode *inode, struct writeback_control *wbc) !is_inode_flag_set(inode, FI_DIRTY_INODE)) return 0; - if (!f2fs_is_checkpoint_ready(sbi)) + if (!f2fs_is_checkpoint_ready(sbi)) { + f2fs_mark_inode_dirty_sync(inode, true); return -ENOSPC; + } /* * We need to balance fs here to prevent from producing dirty node pages -- 2.43.0

8 months, 3 weeks

1
3
0 0

2025

2024

2023

2022

2021

2020

2019

2018

2017

Linux-stable-mirror December 2024