diff options
| author | Andrey Ryabinin <arbn@yandex-team.com> | 2021-02-17 17:30:04 +0300 |
|---|---|---|
| committer | Joerg Roedel <jroedel@suse.de> | 2021-03-04 13:15:56 +0100 |
| commit | 140456f994195b568ecd7fc2287a34eadffef3ca (patch) | |
| tree | 1e4ac114d3b9f5d6aa11e434f54bbe62828b0ecd | |
| parent | 45e606f2726926b04094e1c9bf809bca4884c57f (diff) | |
| download | linux-140456f994195b568ecd7fc2287a34eadffef3ca.tar.gz | |
iommu/amd: Fix sleeping in atomic in increase_address_space()
increase_address_space() calls get_zeroed_page(gfp) under spin_lock with
disabled interrupts. gfp flags passed to increase_address_space() may allow
sleeping, so it comes to this:
BUG: sleeping function called from invalid context at mm/page_alloc.c:4342
in_atomic(): 1, irqs_disabled(): 1, pid: 21555, name: epdcbbf1qnhbsd8
Call Trace:
dump_stack+0x66/0x8b
___might_sleep+0xec/0x110
__alloc_pages_nodemask+0x104/0x300
get_zeroed_page+0x15/0x40
iommu_map_page+0xdd/0x3e0
amd_iommu_map+0x50/0x70
iommu_map+0x106/0x220
vfio_iommu_type1_ioctl+0x76e/0x950 [vfio_iommu_type1]
do_vfs_ioctl+0xa3/0x6f0
ksys_ioctl+0x66/0x70
__x64_sys_ioctl+0x16/0x20
do_syscall_64+0x4e/0x100
entry_SYSCALL_64_after_hwframe+0x44/0xa9
Fix this by moving get_zeroed_page() out of spin_lock/unlock section.
Fixes: 754265bcab ("iommu/amd: Fix race in increase_address_space()")
Signed-off-by: Andrey Ryabinin <arbn@yandex-team.com>
Acked-by: Will Deacon <will@kernel.org>
Cc: <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20210217143004.19165-1-arbn@yandex-team.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
| -rw-r--r-- | drivers/iommu/amd/io_pgtable.c | 10 |
1 files changed, 6 insertions, 4 deletions
diff --git a/drivers/iommu/amd/io_pgtable.c b/drivers/iommu/amd/io_pgtable.c index 1c4961e05c121..bb0ee5c9fde7c 100644 --- a/drivers/iommu/amd/io_pgtable.c +++ b/drivers/iommu/amd/io_pgtable.c @@ -182,6 +182,10 @@ static bool increase_address_space(struct protection_domain *domain, bool ret = true; u64 *pte; + pte = (void *)get_zeroed_page(gfp); + if (!pte) + return false; + spin_lock_irqsave(&domain->lock, flags); if (address <= PM_LEVEL_SIZE(domain->iop.mode)) @@ -191,10 +195,6 @@ static bool increase_address_space(struct protection_domain *domain, if (WARN_ON_ONCE(domain->iop.mode == PAGE_MODE_6_LEVEL)) goto out; - pte = (void *)get_zeroed_page(gfp); - if (!pte) - goto out; - *pte = PM_LEVEL_PDE(domain->iop.mode, iommu_virt_to_phys(domain->iop.root)); domain->iop.root = pte; @@ -208,10 +208,12 @@ static bool increase_address_space(struct protection_domain *domain, */ amd_iommu_domain_set_pgtable(domain, pte, domain->iop.mode); + pte = NULL; ret = true; out: spin_unlock_irqrestore(&domain->lock, flags); + free_page((unsigned long)pte); return ret; } |