FAILED: patch "[PATCH] iommu/amd: Fix sleeping in atomic in increase_address_space()" failed to apply to 4.9-stable tree

The patch below does not apply to the 4.9-stable tree.
If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <[email protected]>.

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 140456f994195b568ecd7fc2287a34eadffef3ca Mon Sep 17 00:00:00 2001
From: Andrey Ryabinin <[email protected]>
Date: Wed, 17 Feb 2021 17:30:04 +0300
Subject: [PATCH] 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.

index 1c4961e05c12..bb0ee5c9fde7 100644
@@ -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;
 }

commit 140456f994195b568ecd7fc2287a34eadffef3ca upstream.

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.

---
 drivers/iommu/amd_iommu.c | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

index 494caaa265af0..8195ff219b48c 100644
@@ -1347,24 +1347,26 @@ static void increase_address_space(struct protection_domain *domain,
 	unsigned long flags;
 	u64 *pte;
 
+	pte = (void *)get_zeroed_page(gfp);
+	if (!pte)
+		return;
+
 	spin_lock_irqsave(&domain->lock, flags);
 
 	if (WARN_ON_ONCE(domain->mode == PAGE_MODE_6_LEVEL))
 		/* address space already 64 bit large */
 		goto out;
 
-	pte = (void *)get_zeroed_page(gfp);
-	if (!pte)
-		goto out;
-
 	*pte             = PM_LEVEL_PDE(domain->mode,
 					iommu_virt_to_phys(domain->pt_root));
 	domain->pt_root  = pte;
 	domain->mode    += 1;
 	domain->updated  = true;
+	pte              = NULL;
 
 out:
 	spin_unlock_irqrestore(&domain->lock, flags);
+	free_page((unsigned long)pte);
 
 	return;
 }

2.26.2

commit 140456f994195b568ecd7fc2287a34eadffef3ca upstream.

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.

---
 drivers/iommu/amd_iommu.c | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

index f4a15d9f2bbb2..8377bd388d673 100644
@@ -1331,24 +1331,26 @@ static void increase_address_space(struct protection_domain *domain,
 	unsigned long flags;
 	u64 *pte;
 
+	pte = (void *)get_zeroed_page(gfp);
+	if (!pte)
+		goto out;
+
 	spin_lock_irqsave(&domain->lock, flags);
 
 	if (WARN_ON_ONCE(domain->mode == PAGE_MODE_6_LEVEL))
 		/* address space already 64 bit large */
 		goto out;
 
-	pte = (void *)get_zeroed_page(gfp);
-	if (!pte)
-		goto out;
-
 	*pte             = PM_LEVEL_PDE(domain->mode,
 					virt_to_phys(domain->pt_root));
 	domain->pt_root  = pte;
 	domain->mode    += 1;
 	domain->updated  = true;
+	pte              = NULL;
 
 out:
 	spin_unlock_irqrestore(&domain->lock, flags);
+	free_page((unsigned long)pte);
 
 	return;
 }

2.26.2

commit 140456f994195b568ecd7fc2287a34eadffef3ca upstream.

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.

---
 drivers/iommu/amd/iommu.c | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

index f0adbc48fd179..9256f84f5ebf1 100644
@@ -1502,6 +1502,10 @@ 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);
 
 	amd_iommu_domain_get_pgtable(domain, &pgtable);

@@ -1513,10 +1517,6 @@ static bool increase_address_space(struct protection_domain *domain,
 	if (WARN_ON_ONCE(pgtable.mode == PAGE_MODE_6_LEVEL))
 		goto out;
 
-	pte = (void *)get_zeroed_page(gfp);
-	if (!pte)
-		goto out;
-
 	*pte = PM_LEVEL_PDE(pgtable.mode, iommu_virt_to_phys(pgtable.root));
 
 	pgtable.root  = pte;

@@ -1530,10 +1530,12 @@ static bool increase_address_space(struct protection_domain *domain,
 	 */
 	amd_iommu_domain_set_pgtable(domain, pte, pgtable.mode);
 
+	pte = NULL;
 	ret = true;
 
 out:
 	spin_unlock_irqrestore(&domain->lock, flags);
+	free_page((unsigned long)pte);
 
 	return ret;
 }

2.26.2

commit 140456f994195b568ecd7fc2287a34eadffef3ca upstream.

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.

---
 drivers/iommu/amd_iommu.c | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

index 7b724f7b27a99..c392930253a30 100644
@@ -1469,25 +1469,27 @@ static bool increase_address_space(struct protection_domain *domain,
 	bool ret = false;
 	u64 *pte;
 
+	pte = (void *)get_zeroed_page(gfp);
+	if (!pte)
+		return false;
+
 	spin_lock_irqsave(&domain->lock, flags);
 
 	if (address <= PM_LEVEL_SIZE(domain->mode) ||
 	    WARN_ON_ONCE(domain->mode == PAGE_MODE_6_LEVEL))
 		goto out;
 
-	pte = (void *)get_zeroed_page(gfp);
-	if (!pte)
-		goto out;
-
 	*pte             = PM_LEVEL_PDE(domain->mode,
 					iommu_virt_to_phys(domain->pt_root));
 	domain->pt_root  = pte;
 	domain->mode    += 1;
 
+	pte = NULL;
 	ret = true;
 
 out:
 	spin_unlock_irqrestore(&domain->lock, flags);
+	free_page((unsigned long)pte);
 
 	return ret;
 }

2.26.2

All now queued up, thanks.

greg k-h