forked from Minki/linux
74ddda71f4
The register_syscore_ops() function takes a mutex and might
sleep. In the IOMMU initialization code it is invoked during
irq-remapping setup already, where irqs are disabled.
This causes a schedule-while-atomic bug:
BUG: sleeping function called from invalid context at kernel/locking/mutex.c:747
in_atomic(): 0, irqs_disabled(): 1, pid: 1, name: swapper/0
no locks held by swapper/0/1.
irq event stamp: 304
hardirqs last enabled at (303): [<ffffffff818a87b6>] _raw_spin_unlock_irqrestore+0x36/0x60
hardirqs last disabled at (304): [<ffffffff8235d440>] enable_IR_x2apic+0x79/0x196
softirqs last enabled at (36): [<ffffffff818ae75f>] __do_softirq+0x35f/0x4ec
softirqs last disabled at (31): [<ffffffff810c1955>] irq_exit+0x105/0x120
CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.13.0-rc2.1.el7a.test.x86_64.debug #1
Hardware name: PowerEdge C6145 /040N24, BIOS 3.5.0 10/28/2014
Call Trace:
dump_stack+0x85/0xca
___might_sleep+0x22a/0x260
__might_sleep+0x4a/0x80
__mutex_lock+0x58/0x960
? iommu_completion_wait.part.17+0xb5/0x160
? register_syscore_ops+0x1d/0x70
? iommu_flush_all_caches+0x120/0x150
mutex_lock_nested+0x1b/0x20
register_syscore_ops+0x1d/0x70
state_next+0x119/0x910
iommu_go_to_state+0x29/0x30
amd_iommu_enable+0x13/0x23
Fix it by moving the register_syscore_ops() call to the next
initialization step, which runs with irqs enabled.
Reported-by: Artem Savkov <asavkov@redhat.com>
Tested-by: Artem Savkov <asavkov@redhat.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Fixes:
|
||
|---|---|---|
| .. | ||
| amd_iommu_init.c | ||
| amd_iommu_proto.h | ||
| amd_iommu_types.h | ||
| amd_iommu_v2.c | ||
| amd_iommu.c | ||
| arm-smmu-v3.c | ||
| arm-smmu.c | ||
| dma-iommu.c | ||
| dmar.c | ||
| exynos-iommu.c | ||
| fsl_pamu_domain.c | ||
| fsl_pamu_domain.h | ||
| fsl_pamu.c | ||
| fsl_pamu.h | ||
| intel_irq_remapping.c | ||
| intel-iommu.c | ||
| intel-svm.c | ||
| io-pgtable-arm-v7s.c | ||
| io-pgtable-arm.c | ||
| io-pgtable.c | ||
| io-pgtable.h | ||
| iommu-sysfs.c | ||
| iommu-traces.c | ||
| iommu.c | ||
| iova.c | ||
| ipmmu-vmsa.c | ||
| irq_remapping.c | ||
| irq_remapping.h | ||
| Kconfig | ||
| Makefile | ||
| msm_iommu_hw-8xxx.h | ||
| msm_iommu.c | ||
| msm_iommu.h | ||
| mtk_iommu_v1.c | ||
| mtk_iommu.c | ||
| mtk_iommu.h | ||
| of_iommu.c | ||
| omap-iommu-debug.c | ||
| omap-iommu.c | ||
| omap-iommu.h | ||
| omap-iopgtable.h | ||
| rockchip-iommu.c | ||
| s390-iommu.c | ||
| tegra-gart.c | ||
| tegra-smmu.c | ||