iommu/vt-d: Avoid memory allocation in iommu_suspend()

JIRA: https://issues.redhat.com/browse/RHEL-10094
Upstream Status: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git

commit 59df44bfb0ca4c3ee1f1c3c5d0ee8e314844799e
Author: Zhang Rui <rui.zhang@intel.com>
Date:   Mon Sep 25 20:04:17 2023 +0800

    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>

(cherry picked from commit 59df44bfb0ca4c3ee1f1c3c5d0ee8e314844799e)
Signed-off-by: Jerry Snitselaar <jsnitsel@redhat.com>
This commit is contained in:
Jerry Snitselaar 2023-09-25 20:04:17 +08:00
parent 399fb58f08
commit 44e68a9a11
2 changed files with 1 additions and 17 deletions

View File

@ -2998,13 +2998,6 @@ 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) {
@ -3024,12 +3017,6 @@ 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)
@ -3061,9 +3048,6 @@ 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 = {

View File

@ -681,7 +681,7 @@ 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 */