6.1-stable review patch. If anyone has any objections, please let me know.
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From: Zhang Rui rui.zhang@intel.com
commit 59df44bfb0ca4c3ee1f1c3c5d0ee8e314844799e upstream.
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: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/iommu/intel/iommu.c | 16 ---------------- drivers/iommu/intel/iommu.h | 2 +- 2 files changed, 1 insertion(+), 17 deletions(-)
--- a/drivers/iommu/intel/iommu.c +++ b/drivers/iommu/intel/iommu.c @@ -3163,13 +3163,6 @@ static int iommu_suspend(void) struct intel_iommu *iommu = NULL; unsigned long flag;
- for_each_active_iommu(iommu, drhd) { - iommu->iommu_state = kcalloc(MAX_SR_DMAR_REGS, sizeof(u32), - GFP_KERNEL); - if (!iommu->iommu_state) - goto nomem; - } - iommu_flush_all();
for_each_active_iommu(iommu, drhd) { @@ -3189,12 +3182,6 @@ static int iommu_suspend(void) raw_spin_unlock_irqrestore(&iommu->register_lock, flag); } return 0; - -nomem: - for_each_active_iommu(iommu, drhd) - kfree(iommu->iommu_state); - - return -ENOMEM; }
static void iommu_resume(void) @@ -3226,9 +3213,6 @@ static void iommu_resume(void)
raw_spin_unlock_irqrestore(&iommu->register_lock, flag); } - - for_each_active_iommu(iommu, drhd) - kfree(iommu->iommu_state); }
static struct syscore_ops iommu_syscore_ops = { --- a/drivers/iommu/intel/iommu.h +++ b/drivers/iommu/intel/iommu.h @@ -595,7 +595,7 @@ struct intel_iommu { struct iopf_queue *iopf_queue; unsigned char iopfq_name[16]; struct q_inval *qi; /* Queued invalidation info */ - u32 *iommu_state; /* Store iommu states between suspend and resume.*/ + u32 iommu_state[MAX_SR_DMAR_REGS]; /* Store iommu states between suspend and resume.*/
#ifdef CONFIG_IRQ_REMAP struct ir_table *ir_table; /* Interrupt remapping info */