| CVE |
Vendors |
Products |
Updated |
CVSS v3.1 |
| In the Linux kernel, the following vulnerability has been resolved:
ftrace: Fix softlockup in ftrace_module_enable
A soft lockup was observed when loading amdgpu module.
If a module has a lot of tracable functions, multiple calls
to kallsyms_lookup can spend too much time in RCU critical
section and with disabled preemption, causing kernel panic.
This is the same issue that was fixed in
commit d0b24b4e91fc ("ftrace: Prevent RCU stall on PREEMPT_VOLUNTARY
kernels") and commit 42ea22e754ba ("ftrace: Add cond_resched() to
ftrace_graph_set_hash()").
Fix it the same way by adding cond_resched() in ftrace_module_enable. |
| In the Linux kernel, the following vulnerability has been resolved:
crypto: aspeed - fix double free caused by devm
The clock obtained via devm_clk_get_enabled() is automatically managed
by devres and will be disabled and freed on driver detach. Manually
calling clk_disable_unprepare() in error path and remove function
causes double free.
Remove the manual clock cleanup in both aspeed_acry_probe()'s error
path and aspeed_acry_remove(). |
| In the Linux kernel, the following vulnerability has been resolved:
PCI: Free released resource after coalescing
release_resource() doesn't actually free the resource or resource list
entry so free the resource list entry to avoid a leak. |
| In the Linux kernel, the following vulnerability has been resolved:
RISC-V: kexec: Fix memory leak of fdt buffer
This is reported by kmemleak detector:
unreferenced object 0xff60000082864000 (size 9588):
comm "kexec", pid 146, jiffies 4294900634 (age 64.788s)
hex dump (first 32 bytes):
d0 0d fe ed 00 00 12 ed 00 00 00 48 00 00 11 40 ...........H...@
00 00 00 28 00 00 00 11 00 00 00 02 00 00 00 00 ...(............
backtrace:
[<00000000f95b17c4>] kmemleak_alloc+0x34/0x3e
[<00000000b9ec8e3e>] kmalloc_order+0x9c/0xc4
[<00000000a95cf02e>] kmalloc_order_trace+0x34/0xb6
[<00000000f01e68b4>] __kmalloc+0x5c2/0x62a
[<000000002bd497b2>] kvmalloc_node+0x66/0xd6
[<00000000906542fa>] of_kexec_alloc_and_setup_fdt+0xa6/0x6ea
[<00000000e1166bde>] elf_kexec_load+0x206/0x4ec
[<0000000036548e09>] kexec_image_load_default+0x40/0x4c
[<0000000079fbe1b4>] sys_kexec_file_load+0x1c4/0x322
[<0000000040c62c03>] ret_from_syscall+0x0/0x2
In elf_kexec_load(), a buffer is allocated via kvmalloc() to store fdt.
While it's not freed back to system when kexec kernel is reloaded or
unloaded. Then memory leak is caused. Fix it by introducing riscv
specific function arch_kimage_file_post_load_cleanup(), and freeing the
buffer there. |
| In the Linux kernel, the following vulnerability has been resolved:
iommu/amd: Improve page fault error reporting
If IOMMU domain for device group is not setup properly then we may hit
IOMMU page fault. Current page fault handler assumes that domain is
always setup and it will hit NULL pointer derefence (see below sample log).
Lets check whether domain is setup or not and log appropriate message.
Sample log:
----------
amdgpu 0000:00:01.0: amdgpu: SE 1, SH per SE 1, CU per SH 8, active_cu_number 6
BUG: kernel NULL pointer dereference, address: 0000000000000058
#PF: supervisor read access in kernel mode
#PF: error_code(0x0000) - not-present page
PGD 0 P4D 0
Oops: 0000 [#1] PREEMPT SMP NOPTI
CPU: 2 PID: 56 Comm: irq/24-AMD-Vi Not tainted 6.2.0-rc2+ #89
Hardware name: xxx
RIP: 0010:report_iommu_fault+0x11/0x90
[...]
Call Trace:
<TASK>
amd_iommu_int_thread+0x60c/0x760
? __pfx_irq_thread_fn+0x10/0x10
irq_thread_fn+0x1f/0x60
irq_thread+0xea/0x1a0
? preempt_count_add+0x6a/0xa0
? __pfx_irq_thread_dtor+0x10/0x10
? __pfx_irq_thread+0x10/0x10
kthread+0xe9/0x110
? __pfx_kthread+0x10/0x10
ret_from_fork+0x2c/0x50
</TASK>
[joro: Edit commit message] |
| In the Linux kernel, the following vulnerability has been resolved:
drm/gud: Fix UBSAN warning
UBSAN complains about invalid value for bool:
[ 101.165172] [drm] Initialized gud 1.0.0 20200422 for 2-3.2:1.0 on minor 1
[ 101.213360] gud 2-3.2:1.0: [drm] fb1: guddrmfb frame buffer device
[ 101.213426] usbcore: registered new interface driver gud
[ 101.989431] ================================================================================
[ 101.989441] UBSAN: invalid-load in linux/include/linux/iosys-map.h:253:9
[ 101.989447] load of value 121 is not a valid value for type '_Bool'
[ 101.989451] CPU: 1 PID: 455 Comm: kworker/1:6 Not tainted 5.18.0-rc5-gud-5.18-rc5 #3
[ 101.989456] Hardware name: Hewlett-Packard HP EliteBook 820 G1/1991, BIOS L71 Ver. 01.44 04/12/2018
[ 101.989459] Workqueue: events_long gud_flush_work [gud]
[ 101.989471] Call Trace:
[ 101.989474] <TASK>
[ 101.989479] dump_stack_lvl+0x49/0x5f
[ 101.989488] dump_stack+0x10/0x12
[ 101.989493] ubsan_epilogue+0x9/0x3b
[ 101.989498] __ubsan_handle_load_invalid_value.cold+0x44/0x49
[ 101.989504] dma_buf_vmap.cold+0x38/0x3d
[ 101.989511] ? find_busiest_group+0x48/0x300
[ 101.989520] drm_gem_shmem_vmap+0x76/0x1b0 [drm_shmem_helper]
[ 101.989528] drm_gem_shmem_object_vmap+0x9/0xb [drm_shmem_helper]
[ 101.989535] drm_gem_vmap+0x26/0x60 [drm]
[ 101.989594] drm_gem_fb_vmap+0x47/0x150 [drm_kms_helper]
[ 101.989630] gud_prep_flush+0xc1/0x710 [gud]
[ 101.989639] ? _raw_spin_lock+0x17/0x40
[ 101.989648] gud_flush_work+0x1e0/0x430 [gud]
[ 101.989653] ? __switch_to+0x11d/0x470
[ 101.989664] process_one_work+0x21f/0x3f0
[ 101.989673] worker_thread+0x200/0x3e0
[ 101.989679] ? rescuer_thread+0x390/0x390
[ 101.989684] kthread+0xfd/0x130
[ 101.989690] ? kthread_complete_and_exit+0x20/0x20
[ 101.989696] ret_from_fork+0x22/0x30
[ 101.989706] </TASK>
[ 101.989708] ================================================================================
The source of this warning is in iosys_map_clear() called from
dma_buf_vmap(). It conditionally sets values based on map->is_iomem. The
iosys_map variables are allocated uninitialized on the stack leading to
->is_iomem having all kinds of values and not only 0/1.
Fix this by zeroing the iosys_map variables. |
| In the Linux kernel, the following vulnerability has been resolved:
media: dvb-usb: fix memory leak in dvb_usb_adapter_init()
Syzbot reports a memory leak in "dvb_usb_adapter_init()".
The leak is due to not accounting for and freeing current iteration's
adapter->priv in case of an error. Currently if an error occurs,
it will exit before incrementing "num_adapters_initalized",
which is used as a reference counter to free all adap->priv
in "dvb_usb_adapter_exit()". There are multiple error paths that
can exit from before incrementing the counter. Including the
error handling paths for "dvb_usb_adapter_stream_init()",
"dvb_usb_adapter_dvb_init()" and "dvb_usb_adapter_frontend_init()"
within "dvb_usb_adapter_init()".
This means that in case of an error in any of these functions the
current iteration is not accounted for and the current iteration's
adap->priv is not freed.
Fix this by freeing the current iteration's adap->priv in the
"stream_init_err:" label in the error path. The rest of the
(accounted for) adap->priv objects are freed in dvb_usb_adapter_exit()
as expected using the num_adapters_initalized variable.
Syzbot report:
BUG: memory leak
unreferenced object 0xffff8881172f1a00 (size 512):
comm "kworker/0:2", pid 139, jiffies 4294994873 (age 10.960s)
hex dump (first 32 bytes):
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
backtrace:
[<ffffffff844af012>] dvb_usb_adapter_init drivers/media/usb/dvb-usb/dvb-usb-init.c:75 [inline]
[<ffffffff844af012>] dvb_usb_init drivers/media/usb/dvb-usb/dvb-usb-init.c:184 [inline]
[<ffffffff844af012>] dvb_usb_device_init.cold+0x4e5/0x79e drivers/media/usb/dvb-usb/dvb-usb-init.c:308
[<ffffffff830db21d>] dib0700_probe+0x8d/0x1b0 drivers/media/usb/dvb-usb/dib0700_core.c:883
[<ffffffff82d3fdc7>] usb_probe_interface+0x177/0x370 drivers/usb/core/driver.c:396
[<ffffffff8274ab37>] call_driver_probe drivers/base/dd.c:542 [inline]
[<ffffffff8274ab37>] really_probe.part.0+0xe7/0x310 drivers/base/dd.c:621
[<ffffffff8274ae6c>] really_probe drivers/base/dd.c:583 [inline]
[<ffffffff8274ae6c>] __driver_probe_device+0x10c/0x1e0 drivers/base/dd.c:752
[<ffffffff8274af6a>] driver_probe_device+0x2a/0x120 drivers/base/dd.c:782
[<ffffffff8274b786>] __device_attach_driver+0xf6/0x140 drivers/base/dd.c:899
[<ffffffff82747c87>] bus_for_each_drv+0xb7/0x100 drivers/base/bus.c:427
[<ffffffff8274b352>] __device_attach+0x122/0x260 drivers/base/dd.c:970
[<ffffffff827498f6>] bus_probe_device+0xc6/0xe0 drivers/base/bus.c:487
[<ffffffff82745cdb>] device_add+0x5fb/0xdf0 drivers/base/core.c:3405
[<ffffffff82d3d202>] usb_set_configuration+0x8f2/0xb80 drivers/usb/core/message.c:2170
[<ffffffff82d4dbfc>] usb_generic_driver_probe+0x8c/0xc0 drivers/usb/core/generic.c:238
[<ffffffff82d3f49c>] usb_probe_device+0x5c/0x140 drivers/usb/core/driver.c:293
[<ffffffff8274ab37>] call_driver_probe drivers/base/dd.c:542 [inline]
[<ffffffff8274ab37>] really_probe.part.0+0xe7/0x310 drivers/base/dd.c:621
[<ffffffff8274ae6c>] really_probe drivers/base/dd.c:583 [inline]
[<ffffffff8274ae6c>] __driver_probe_device+0x10c/0x1e0 drivers/base/dd.c:752 |
| In the Linux kernel, the following vulnerability has been resolved:
dm: verity-loadpin: Only trust verity targets with enforcement
Verity targets can be configured to ignore corrupted data blocks.
LoadPin must only trust verity targets that are configured to
perform some kind of enforcement when data corruption is detected,
like returning an error, restarting the system or triggering a
panic. |
| In the Linux kernel, the following vulnerability has been resolved:
regulator: core: Use different devices for resource allocation and DT lookup
Following by the below discussion, there's the potential UAF issue
between regulator and mfd.
https://lore.kernel.org/all/20221128143601.1698148-1-yangyingliang@huawei.com/
From the analysis of Yingliang
CPU A |CPU B
mt6370_probe() |
devm_mfd_add_devices() |
|mt6370_regulator_probe()
| regulator_register()
| //allocate init_data and add it to devres
| regulator_of_get_init_data()
i2c_unregister_device() |
device_del() |
devres_release_all() |
// init_data is freed |
release_nodes() |
| // using init_data causes UAF
| regulator_register()
It's common to use mfd core to create child device for the regulator.
In order to do the DT lookup for init data, the child that registered
the regulator would pass its parent as the parameter. And this causes
init data resource allocated to its parent, not itself. The issue happen
when parent device is going to release and regulator core is still doing
some operation of init data constraint for the regulator of child device.
To fix it, this patch expand 'regulator_register' API to use the
different devices for init data allocation and DT lookup. |
| In the Linux kernel, the following vulnerability has been resolved:
perf/x86/intel/uncore: Fix reference count leak in snr_uncore_mmio_map()
pci_get_device() will increase the reference count for the returned
pci_dev, so snr_uncore_get_mc_dev() will return a pci_dev with its
reference count increased. We need to call pci_dev_put() to decrease the
reference count. Let's add the missing pci_dev_put(). |
| In the Linux kernel, the following vulnerability has been resolved:
misc: pci_endpoint_test: Fix pci_endpoint_test_{copy,write,read}() panic
The dma_map_single() doesn't permit zero length mapping. It causes a follow
panic.
A panic was reported on arm64:
[ 60.137988] ------------[ cut here ]------------
[ 60.142630] kernel BUG at kernel/dma/swiotlb.c:624!
[ 60.147508] Internal error: Oops - BUG: 0 [#1] PREEMPT SMP
[ 60.152992] Modules linked in: dw_hdmi_cec crct10dif_ce simple_bridge rcar_fdp1 vsp1 rcar_vin videobuf2_vmalloc rcar_csi2 v4l
2_mem2mem videobuf2_dma_contig videobuf2_memops pci_endpoint_test videobuf2_v4l2 videobuf2_common rcar_fcp v4l2_fwnode v4l2_asyn
c videodev mc gpio_bd9571mwv max9611 pwm_rcar ccree at24 authenc libdes phy_rcar_gen3_usb3 usb_dmac display_connector pwm_bl
[ 60.186252] CPU: 0 PID: 508 Comm: pcitest Not tainted 6.0.0-rc1rpci-dev+ #237
[ 60.193387] Hardware name: Renesas Salvator-X 2nd version board based on r8a77951 (DT)
[ 60.201302] pstate: 00000005 (nzcv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
[ 60.208263] pc : swiotlb_tbl_map_single+0x2c0/0x590
[ 60.213149] lr : swiotlb_map+0x88/0x1f0
[ 60.216982] sp : ffff80000a883bc0
[ 60.220292] x29: ffff80000a883bc0 x28: 0000000000000000 x27: 0000000000000000
[ 60.227430] x26: 0000000000000000 x25: ffff0004c0da20d0 x24: ffff80000a1f77c0
[ 60.234567] x23: 0000000000000002 x22: 0001000040000010 x21: 000000007a000000
[ 60.241703] x20: 0000000000200000 x19: 0000000000000000 x18: 0000000000000000
[ 60.248840] x17: 0000000000000000 x16: 0000000000000000 x15: ffff0006ff7b9180
[ 60.255977] x14: ffff0006ff7b9180 x13: 0000000000000000 x12: 0000000000000000
[ 60.263113] x11: 0000000000000000 x10: 0000000000000000 x9 : 0000000000000000
[ 60.270249] x8 : 0001000000000010 x7 : ffff0004c6754b20 x6 : 0000000000000000
[ 60.277385] x5 : ffff0004c0da2090 x4 : 0000000000000000 x3 : 0000000000000001
[ 60.284521] x2 : 0000000040000000 x1 : 0000000000000000 x0 : 0000000040000010
[ 60.291658] Call trace:
[ 60.294100] swiotlb_tbl_map_single+0x2c0/0x590
[ 60.298629] swiotlb_map+0x88/0x1f0
[ 60.302115] dma_map_page_attrs+0x188/0x230
[ 60.306299] pci_endpoint_test_ioctl+0x5e4/0xd90 [pci_endpoint_test]
[ 60.312660] __arm64_sys_ioctl+0xa8/0xf0
[ 60.316583] invoke_syscall+0x44/0x108
[ 60.320334] el0_svc_common.constprop.0+0xcc/0xf0
[ 60.325038] do_el0_svc+0x2c/0xb8
[ 60.328351] el0_svc+0x2c/0x88
[ 60.331406] el0t_64_sync_handler+0xb8/0xc0
[ 60.335587] el0t_64_sync+0x18c/0x190
[ 60.339251] Code: 52800013 d2e00414 35fff45c d503201f (d4210000)
[ 60.345344] ---[ end trace 0000000000000000 ]---
To fix it, this patch adds a checking the payload length if it is zero. |
| In the Linux kernel, the following vulnerability has been resolved:
md/raid0, raid10: Don't set discard sectors for request queue
It should use disk_stack_limits to get a proper max_discard_sectors
rather than setting a value by stack drivers.
And there is a bug. If all member disks are rotational devices,
raid0/raid10 set max_discard_sectors. So the member devices are
not ssd/nvme, but raid0/raid10 export the wrong value. It reports
warning messages in function __blkdev_issue_discard when mkfs.xfs
like this:
[ 4616.022599] ------------[ cut here ]------------
[ 4616.027779] WARNING: CPU: 4 PID: 99634 at block/blk-lib.c:50 __blkdev_issue_discard+0x16a/0x1a0
[ 4616.140663] RIP: 0010:__blkdev_issue_discard+0x16a/0x1a0
[ 4616.146601] Code: 24 4c 89 20 31 c0 e9 fe fe ff ff c1 e8 09 8d 48 ff 4c 89 f0 4c 09 e8 48 85 c1 0f 84 55 ff ff ff b8 ea ff ff ff e9 df fe ff ff <0f> 0b 48 8d 74 24 08 e8 ea d6 00 00 48 c7 c6 20 1e 89 ab 48 c7 c7
[ 4616.167567] RSP: 0018:ffffaab88cbffca8 EFLAGS: 00010246
[ 4616.173406] RAX: ffff9ba1f9e44678 RBX: 0000000000000000 RCX: ffff9ba1c9792080
[ 4616.181376] RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff9ba1c9792080
[ 4616.189345] RBP: 0000000000000cc0 R08: ffffaab88cbffd10 R09: 0000000000000000
[ 4616.197317] R10: 0000000000000012 R11: 0000000000000000 R12: 0000000000000000
[ 4616.205288] R13: 0000000000400000 R14: 0000000000000cc0 R15: ffff9ba1c9792080
[ 4616.213259] FS: 00007f9a5534e980(0000) GS:ffff9ba1b7c80000(0000) knlGS:0000000000000000
[ 4616.222298] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 4616.228719] CR2: 000055a390a4c518 CR3: 0000000123e40006 CR4: 00000000001706e0
[ 4616.236689] Call Trace:
[ 4616.239428] blkdev_issue_discard+0x52/0xb0
[ 4616.244108] blkdev_common_ioctl+0x43c/0xa00
[ 4616.248883] blkdev_ioctl+0x116/0x280
[ 4616.252977] __x64_sys_ioctl+0x8a/0xc0
[ 4616.257163] do_syscall_64+0x5c/0x90
[ 4616.261164] ? handle_mm_fault+0xc5/0x2a0
[ 4616.265652] ? do_user_addr_fault+0x1d8/0x690
[ 4616.270527] ? do_syscall_64+0x69/0x90
[ 4616.274717] ? exc_page_fault+0x62/0x150
[ 4616.279097] entry_SYSCALL_64_after_hwframe+0x63/0xcd
[ 4616.284748] RIP: 0033:0x7f9a55398c6b |
| NVIDIA Display Driver for Linux contains a vulnerability where an attacker might be able to use a race condition to escalate privileges. A successful exploit of this vulnerability might lead to code execution, escalation of privileges, data tampering, denial of service, and information disclosure. |
| In the Linux kernel, the following vulnerability has been resolved:
erofs: kill hooked chains to avoid loops on deduplicated compressed images
After heavily stressing EROFS with several images which include a
hand-crafted image of repeated patterns for more than 46 days, I found
two chains could be linked with each other almost simultaneously and
form a loop so that the entire loop won't be submitted. As a
consequence, the corresponding file pages will remain locked forever.
It can be _only_ observed on data-deduplicated compressed images.
For example, consider two chains with five pclusters in total:
Chain 1: 2->3->4->5 -- The tail pcluster is 5;
Chain 2: 5->1->2 -- The tail pcluster is 2.
Chain 2 could link to Chain 1 with pcluster 5; and Chain 1 could link
to Chain 2 at the same time with pcluster 2.
Since hooked chains are all linked locklessly now, I have no idea how
to simply avoid the race. Instead, let's avoid hooked chains completely
until I could work out a proper way to fix this and end users finally
tell us that it's needed to add it back.
Actually, this optimization can be found with multi-threaded workloads
(especially even more often on deduplicated compressed images), yet I'm
not sure about the overall system impacts of not having this compared
with implementation complexity. |
| In the Linux kernel, the following vulnerability has been resolved:
slab: Avoid race on slab->obj_exts in alloc_slab_obj_exts
If two competing threads enter alloc_slab_obj_exts() and one of them
fails to allocate the object extension vector, it might override the
valid slab->obj_exts allocated by the other thread with
OBJEXTS_ALLOC_FAIL. This will cause the thread that lost this race and
expects a valid pointer to dereference a NULL pointer later on.
Update slab->obj_exts atomically using cmpxchg() to avoid
slab->obj_exts overrides by racing threads.
Thanks for Vlastimil and Suren's help with debugging. |
| In the Linux kernel, the following vulnerability has been resolved:
drm/sysfb: Do not dereference NULL pointer in plane reset
The plane state in __drm_gem_reset_shadow_plane() can be NULL. Do not
deref that pointer, but forward NULL to the other plane-reset helpers.
Clears plane->state to NULL.
v2:
- fix typo in commit description (Javier) |
| In the Linux kernel, the following vulnerability has been resolved:
arm64: mte: Do not warn if the page is already tagged in copy_highpage()
The arm64 copy_highpage() assumes that the destination page is newly
allocated and not MTE-tagged (PG_mte_tagged unset) and warns
accordingly. However, following commit 060913999d7a ("mm: migrate:
support poisoned recover from migrate folio"), folio_mc_copy() is called
before __folio_migrate_mapping(). If the latter fails (-EAGAIN), the
copy will be done again to the same destination page. Since
copy_highpage() already set the PG_mte_tagged flag, this second copy
will warn.
Replace the WARN_ON_ONCE(page already tagged) in the arm64
copy_highpage() with a comment. |
| In the Linux kernel, the following vulnerability has been resolved:
perf tool x86: Fix perf_env memory leak
Found by leak sanitizer:
```
==1632594==ERROR: LeakSanitizer: detected memory leaks
Direct leak of 21 byte(s) in 1 object(s) allocated from:
#0 0x7f2953a7077b in __interceptor_strdup ../../../../src/libsanitizer/asan/asan_interceptors.cpp:439
#1 0x556701d6fbbf in perf_env__read_cpuid util/env.c:369
#2 0x556701d70589 in perf_env__cpuid util/env.c:465
#3 0x55670204bba2 in x86__is_amd_cpu arch/x86/util/env.c:14
#4 0x5567020487a2 in arch__post_evsel_config arch/x86/util/evsel.c:83
#5 0x556701d8f78b in evsel__config util/evsel.c:1366
#6 0x556701ef5872 in evlist__config util/record.c:108
#7 0x556701cd6bcd in test__PERF_RECORD tests/perf-record.c:112
#8 0x556701cacd07 in run_test tests/builtin-test.c:236
#9 0x556701cacfac in test_and_print tests/builtin-test.c:265
#10 0x556701cadddb in __cmd_test tests/builtin-test.c:402
#11 0x556701caf2aa in cmd_test tests/builtin-test.c:559
#12 0x556701d3b557 in run_builtin tools/perf/perf.c:323
#13 0x556701d3bac8 in handle_internal_command tools/perf/perf.c:377
#14 0x556701d3be90 in run_argv tools/perf/perf.c:421
#15 0x556701d3c3f8 in main tools/perf/perf.c:537
#16 0x7f2952a46189 in __libc_start_call_main ../sysdeps/nptl/libc_start_call_main.h:58
SUMMARY: AddressSanitizer: 21 byte(s) leaked in 1 allocation(s).
``` |
| In the Linux kernel, the following vulnerability has been resolved:
iommu/sprd: Release dma buffer to avoid memory leak
When attaching to a domain, the driver would alloc a DMA buffer which
is used to store address mapping table, and it need to be released
when the IOMMU domain is freed. |
| In the Linux kernel, the following vulnerability has been resolved:
9p/trans_fd: p9_fd_request: kick rx thread if EPOLLIN
p9_read_work() doesn't set Rworksched and doesn't do schedule_work(m->rq)
if list_empty(&m->req_list).
However, if the pipe is full, we need to read more data and this used to
work prior to commit aaec5a95d59615 ("pipe_read: don't wake up the writer
if the pipe is still full").
p9_read_work() does p9_fd_read() -> ... -> anon_pipe_read() which (before
the commit above) triggered the unnecessary wakeup. This wakeup calls
p9_pollwake() which kicks p9_poll_workfn() -> p9_poll_mux(), p9_poll_mux()
will notice EPOLLIN and schedule_work(&m->rq).
This no longer happens after the optimization above, change p9_fd_request()
to use p9_poll_mux() instead of only checking for EPOLLOUT. |
