Linux kernel source tree
Go to file
Zhang Rui 59df44bfb0 iommu/vt-d: Avoid memory allocation in iommu_suspend()
The iommu_suspend() syscore suspend callback is invoked with IRQ disabled.
Allocating memory with the GFP_KERNEL flag may re-enable IRQs during
the suspend callback, which can cause intermittent suspend/hibernation
problems with the following kernel traces:

Calling iommu_suspend+0x0/0x1d0
------------[ cut here ]------------
WARNING: CPU: 0 PID: 15 at kernel/time/timekeeping.c:868 ktime_get+0x9b/0xb0
...
CPU: 0 PID: 15 Comm: rcu_preempt Tainted: G     U      E      6.3-intel #r1
RIP: 0010:ktime_get+0x9b/0xb0
...
Call Trace:
 <IRQ>
 tick_sched_timer+0x22/0x90
 ? __pfx_tick_sched_timer+0x10/0x10
 __hrtimer_run_queues+0x111/0x2b0
 hrtimer_interrupt+0xfa/0x230
 __sysvec_apic_timer_interrupt+0x63/0x140
 sysvec_apic_timer_interrupt+0x7b/0xa0
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1f/0x30
...
------------[ cut here ]------------
Interrupts enabled after iommu_suspend+0x0/0x1d0
WARNING: CPU: 0 PID: 27420 at drivers/base/syscore.c:68 syscore_suspend+0x147/0x270
CPU: 0 PID: 27420 Comm: rtcwake Tainted: G     U  W   E      6.3-intel #r1
RIP: 0010:syscore_suspend+0x147/0x270
...
Call Trace:
 <TASK>
 hibernation_snapshot+0x25b/0x670
 hibernate+0xcd/0x390
 state_store+0xcf/0xe0
 kobj_attr_store+0x13/0x30
 sysfs_kf_write+0x3f/0x50
 kernfs_fop_write_iter+0x128/0x200
 vfs_write+0x1fd/0x3c0
 ksys_write+0x6f/0xf0
 __x64_sys_write+0x1d/0x30
 do_syscall_64+0x3b/0x90
 entry_SYSCALL_64_after_hwframe+0x72/0xdc

Given that only 4 words memory is needed, avoid the memory allocation in
iommu_suspend().

CC: stable@kernel.org
Fixes: 33e0715710 ("iommu/vt-d: Avoid GFP_ATOMIC where it is not needed")
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
Tested-by: Ooi, Chin Hao <chin.hao.ooi@intel.com>
Link: https://lore.kernel.org/r/20230921093956.234692-1-rui.zhang@intel.com
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Link: https://lore.kernel.org/r/20230925120417.55977-2-baolu.lu@linux.intel.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2023-09-25 16:10:36 +02:00
arch ARM: 2023-09-24 14:14:35 -07:00
block blk-mq: fix tags UAF when shrinking q->nr_hw_queues 2023-09-11 16:17:34 -06:00
certs certs: Reference revocation list for all keyrings 2023-08-17 20:12:41 +00:00
crypto crypto: sm2 - Fix crash caused by uninitialized context 2023-09-20 13:10:10 +08:00
Documentation Arm SMMU fixes for 6.6 -rc 2023-09-25 11:34:53 +02:00
drivers iommu/vt-d: Avoid memory allocation in iommu_suspend() 2023-09-25 16:10:36 +02:00
fs Tracing fixes for 6.6-rc2: 2023-09-24 13:55:34 -07:00
include ARM: 2023-09-24 14:14:35 -07:00
init workqueue: Changes for v6.6 2023-09-01 16:06:32 -07:00
io_uring io_uring/net: fix iter retargeting for selected buf 2023-09-14 10:12:55 -06:00
ipc Add x86 shadow stack support 2023-08-31 12:20:12 -07:00
kernel Tracing fixes for 6.6-rc2: 2023-09-24 13:55:34 -07:00
lib argv_split: fix kernel-doc warnings 2023-09-19 13:21:33 -07:00
LICENSES LICENSES: Add the copyleft-next-0.3.1 license 2022-11-08 15:44:01 +01:00
mm 13 hotfixes, 10 of which pertain to post-6.5 issues. The other 3 are 2023-09-23 11:51:16 -07:00
net Networking fixes for 6.6-rc2, including fixes from netfilter and bpf 2023-09-21 11:28:16 -07:00
rust Documentation work keeps chugging along; stuff for 6.6 includes: 2023-08-30 20:05:42 -07:00
samples VFIO updates for v6.6-rc1 2023-08-30 20:36:01 -07:00
scripts 13 hotfixes, 10 of which pertain to post-6.5 issues. The other 3 are 2023-09-23 11:51:16 -07:00
security selinux: fix handling of empty opts in selinux_fs_context_submount() 2023-09-12 17:31:08 -04:00
sound ASoC: Fixes for v6.6 2023-09-20 15:02:16 +02:00
tools ARM: 2023-09-24 14:14:35 -07:00
usr initramfs: Encode dependency on KBUILD_BUILD_TIMESTAMP 2023-06-06 17:54:49 +09:00
virt ARM: 2023-09-07 13:52:20 -07:00
.clang-format iommu: Add for_each_group_device() 2023-05-23 08:15:51 +02:00
.cocciconfig
.get_maintainer.ignore get_maintainer: add Alan to .get_maintainer.ignore 2022-08-20 15:17:44 -07:00
.gitattributes .gitattributes: set diff driver for Rust source code files 2023-05-31 17:48:25 +02:00
.gitignore kbuild: rpm-pkg: rename binkernel.spec to kernel.spec 2023-07-25 00:59:33 +09:00
.mailmap for-linus-2023083101 2023-09-01 12:31:44 -07:00
.rustfmt.toml rust: add .rustfmt.toml 2022-09-28 09:02:20 +02:00
COPYING COPYING: state that all contributions really are covered by this file 2020-02-10 13:32:20 -08:00
CREDITS USB: Remove Wireless USB and UWB documentation 2023-08-09 14:17:32 +02:00
Kbuild Kbuild updates for v6.1 2022-10-10 12:00:45 -07:00
Kconfig kbuild: ensure full rebuild when the compiler is updated 2020-05-12 13:28:33 +09:00
MAINTAINERS gpio fixes for v6.6-rc3 2023-09-23 11:56:57 -07:00
Makefile Linux 6.6-rc3 2023-09-24 14:31:13 -07:00
README Drop all 00-INDEX files from Documentation/ 2018-09-09 15:08:58 -06:00

Linux kernel
============

There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.  The formatted documentation can also be read online at:

    https://www.kernel.org/doc/html/latest/

There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.

Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.