LinuxKPI: Allow wake_up to be executed within a critical section

by replaceing of spin_lock() call with spin_lock_irqsave()

This fixes following panic in drm-kmod:

panic: mi_switch: switch in a critical section
cpuid = 2
time = 1636939794
KDB: stack backtrace:
db_trace_self_wrapper() at db_trace_self_wrapper+0x2b
vpanic() at vpanic+0x187
panic() at panic+0x43
mi_switch() at mi_switch+0x198
__mtx_lock_sleep() at __mtx_lock_sleep+0x1c9
__mtx_lock_flags() at __mtx_lock_flags+0xa2
linux_wake_up() at linux_wake_up+0x38
__active_retire() at __active_retire+0xb7
dma_fence_signal() at dma_fence_signal+0x100
dma_resv_add_shared_fence() at dma_resv_add_shared_fence+0x96
i915_gem_do_execbuffer() at i915_gem_do_execbuffer+0x11d0
i915_gem_execbuffer2_ioctl() at i915_gem_execbuffer2_ioctl+0x19a
drm_ioctl_kernel() at drm_ioctl_kernel+0x72
drm_ioctl() at drm_ioctl+0x2c4
linux_file_ioctl() at linux_file_ioctl+0x297
kern_ioctl() at kern_ioctl+0x1dc
sys_ioctl() at sys_ioctl+0x124
amd64_syscall() at amd64_syscall+0x124
fast_syscall_common() at fast_syscall_common+0xf8
--- syscall (54, FreeBSD ELF64, sys_ioctl)

MFC after:	1 week
Reviewed by:	manu
Reported by:	Graham Perrin <grahamperrin_AT_gmail_DOT_com>
PR:		261166
Differential Revision:	https://reviews.freebsd.org/D33888
This commit is contained in:
Vladimir Kondratyev 2022-01-18 23:14:13 +03:00
parent 02ea603302
commit 89889ab470

View File

@ -202,9 +202,11 @@ void
linux_wake_up(wait_queue_head_t *wqh, unsigned int state, int nr, bool locked)
{
wait_queue_t *pos, *next;
unsigned long flags;
if (!locked)
spin_lock(&wqh->lock);
spin_lock_irqsave(&wqh->lock, flags);
list_for_each_entry_safe(pos, next, &wqh->task_list, task_list) {
if (pos->func == NULL) {
if (wake_up_task(pos->private, state) != 0 && --nr == 0)
@ -215,7 +217,7 @@ linux_wake_up(wait_queue_head_t *wqh, unsigned int state, int nr, bool locked)
}
}
if (!locked)
spin_unlock(&wqh->lock);
spin_unlock_irqrestore(&wqh->lock, flags);
}
void