29298c85a8
[ Upstream commit 59df44bfb0ca4c3ee1f1c3c5d0ee8e314844799e ] 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: 33e07157105e ("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> Signed-off-by: Sasha Levin <sashal@kernel.org>
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.