The patch below does not apply to the 4.14-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 <stable(a)vger.kernel.org>.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
>From 9d4a0d4cdc8b5904ec7c9b9e04bab3e9e60d7a74 Mon Sep 17 00:00:00 2001
From: Andrey Grodzovsky <andrey.grodzovsky(a)amd.com>
Date: Thu, 5 Jul 2018 14:49:34 -0400
Subject: [PATCH] drm/amdgpu: Verify root PD is mapped into kernel address
space (v4)
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
Problem: When PD/PT update made by CPU root PD was not yet mapped causing
page fault.
Fix: Verify root PD is mapped into CPU address space.
v2:
Make sure that we add the root PD to the relocated list
since then it's get mapped into CPU address space bt default
in amdgpu_vm_update_directories.
v3:
Drop change to not move kernel type BOs to evicted list.
v4:
Remove redundant bo move to relocated list.
Link: https://bugs.freedesktop.org/show_bug.cgi?id=107065
Signed-off-by: Andrey Grodzovsky <andrey.grodzovsky(a)amd.com>
Reviewed-by: Christian König <christian.koenig(a)amd.com>
Reviewed-by: Junwei Zhang <Jerry.Zhang(a)amd.com>
Signed-off-by: Alex Deucher <alexander.deucher(a)amd.com>
Cc: stable(a)vger.kernel.org
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
index edf16b2b957a..fdcb498f6d19 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
@@ -107,6 +107,9 @@ static void amdgpu_vm_bo_base_init(struct amdgpu_vm_bo_base *base,
return;
list_add_tail(&base->bo_list, &bo->va);
+ if (bo->tbo.type == ttm_bo_type_kernel)
+ list_move(&base->vm_status, &vm->relocated);
+
if (bo->tbo.resv != vm->root.base.bo->tbo.resv)
return;
@@ -468,7 +471,6 @@ static int amdgpu_vm_alloc_levels(struct amdgpu_device *adev,
pt->parent = amdgpu_bo_ref(parent->base.bo);
amdgpu_vm_bo_base_init(&entry->base, vm, pt);
- list_move(&entry->base.vm_status, &vm->relocated);
}
if (level < AMDGPU_VM_PTB) {
The patch below does not apply to the 4.17-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 <stable(a)vger.kernel.org>.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
>From 9d4a0d4cdc8b5904ec7c9b9e04bab3e9e60d7a74 Mon Sep 17 00:00:00 2001
From: Andrey Grodzovsky <andrey.grodzovsky(a)amd.com>
Date: Thu, 5 Jul 2018 14:49:34 -0400
Subject: [PATCH] drm/amdgpu: Verify root PD is mapped into kernel address
space (v4)
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
Problem: When PD/PT update made by CPU root PD was not yet mapped causing
page fault.
Fix: Verify root PD is mapped into CPU address space.
v2:
Make sure that we add the root PD to the relocated list
since then it's get mapped into CPU address space bt default
in amdgpu_vm_update_directories.
v3:
Drop change to not move kernel type BOs to evicted list.
v4:
Remove redundant bo move to relocated list.
Link: https://bugs.freedesktop.org/show_bug.cgi?id=107065
Signed-off-by: Andrey Grodzovsky <andrey.grodzovsky(a)amd.com>
Reviewed-by: Christian König <christian.koenig(a)amd.com>
Reviewed-by: Junwei Zhang <Jerry.Zhang(a)amd.com>
Signed-off-by: Alex Deucher <alexander.deucher(a)amd.com>
Cc: stable(a)vger.kernel.org
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
index edf16b2b957a..fdcb498f6d19 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
@@ -107,6 +107,9 @@ static void amdgpu_vm_bo_base_init(struct amdgpu_vm_bo_base *base,
return;
list_add_tail(&base->bo_list, &bo->va);
+ if (bo->tbo.type == ttm_bo_type_kernel)
+ list_move(&base->vm_status, &vm->relocated);
+
if (bo->tbo.resv != vm->root.base.bo->tbo.resv)
return;
@@ -468,7 +471,6 @@ static int amdgpu_vm_alloc_levels(struct amdgpu_device *adev,
pt->parent = amdgpu_bo_ref(parent->base.bo);
amdgpu_vm_bo_base_init(&entry->base, vm, pt);
- list_move(&entry->base.vm_status, &vm->relocated);
}
if (level < AMDGPU_VM_PTB) {
The patch below does not apply to the 4.14-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 <stable(a)vger.kernel.org>.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
>From 76fa4975f3ed12d15762bc979ca44078598ed8ee Mon Sep 17 00:00:00 2001
From: Alexey Kardashevskiy <aik(a)ozlabs.ru>
Date: Tue, 17 Jul 2018 17:19:13 +1000
Subject: [PATCH] KVM: PPC: Check if IOMMU page is contained in the pinned
physical page
A VM which has:
- a DMA capable device passed through to it (eg. network card);
- running a malicious kernel that ignores H_PUT_TCE failure;
- capability of using IOMMU pages bigger that physical pages
can create an IOMMU mapping that exposes (for example) 16MB of
the host physical memory to the device when only 64K was allocated to the VM.
The remaining 16MB - 64K will be some other content of host memory, possibly
including pages of the VM, but also pages of host kernel memory, host
programs or other VMs.
The attacking VM does not control the location of the page it can map,
and is only allowed to map as many pages as it has pages of RAM.
We already have a check in drivers/vfio/vfio_iommu_spapr_tce.c that
an IOMMU page is contained in the physical page so the PCI hardware won't
get access to unassigned host memory; however this check is missing in
the KVM fastpath (H_PUT_TCE accelerated code). We were lucky so far and
did not hit this yet as the very first time when the mapping happens
we do not have tbl::it_userspace allocated yet and fall back to
the userspace which in turn calls VFIO IOMMU driver, this fails and
the guest does not retry,
This stores the smallest preregistered page size in the preregistered
region descriptor and changes the mm_iommu_xxx API to check this against
the IOMMU page size.
This calculates maximum page size as a minimum of the natural region
alignment and compound page size. For the page shift this uses the shift
returned by find_linux_pte() which indicates how the page is mapped to
the current userspace - if the page is huge and this is not a zero, then
it is a leaf pte and the page is mapped within the range.
Fixes: 121f80ba68f1 ("KVM: PPC: VFIO: Add in-kernel acceleration for VFIO")
Cc: stable(a)vger.kernel.org # v4.12+
Signed-off-by: Alexey Kardashevskiy <aik(a)ozlabs.ru>
Reviewed-by: David Gibson <david(a)gibson.dropbear.id.au>
Signed-off-by: Michael Ellerman <mpe(a)ellerman.id.au>
diff --git a/arch/powerpc/include/asm/mmu_context.h b/arch/powerpc/include/asm/mmu_context.h
index 896efa559996..79d570cbf332 100644
--- a/arch/powerpc/include/asm/mmu_context.h
+++ b/arch/powerpc/include/asm/mmu_context.h
@@ -35,9 +35,9 @@ extern struct mm_iommu_table_group_mem_t *mm_iommu_lookup_rm(
extern struct mm_iommu_table_group_mem_t *mm_iommu_find(struct mm_struct *mm,
unsigned long ua, unsigned long entries);
extern long mm_iommu_ua_to_hpa(struct mm_iommu_table_group_mem_t *mem,
- unsigned long ua, unsigned long *hpa);
+ unsigned long ua, unsigned int pageshift, unsigned long *hpa);
extern long mm_iommu_ua_to_hpa_rm(struct mm_iommu_table_group_mem_t *mem,
- unsigned long ua, unsigned long *hpa);
+ unsigned long ua, unsigned int pageshift, unsigned long *hpa);
extern long mm_iommu_mapped_inc(struct mm_iommu_table_group_mem_t *mem);
extern void mm_iommu_mapped_dec(struct mm_iommu_table_group_mem_t *mem);
#endif
diff --git a/arch/powerpc/kvm/book3s_64_vio.c b/arch/powerpc/kvm/book3s_64_vio.c
index d066e37551ec..8c456fa691a5 100644
--- a/arch/powerpc/kvm/book3s_64_vio.c
+++ b/arch/powerpc/kvm/book3s_64_vio.c
@@ -449,7 +449,7 @@ long kvmppc_tce_iommu_do_map(struct kvm *kvm, struct iommu_table *tbl,
/* This only handles v2 IOMMU type, v1 is handled via ioctl() */
return H_TOO_HARD;
- if (WARN_ON_ONCE(mm_iommu_ua_to_hpa(mem, ua, &hpa)))
+ if (WARN_ON_ONCE(mm_iommu_ua_to_hpa(mem, ua, tbl->it_page_shift, &hpa)))
return H_HARDWARE;
if (mm_iommu_mapped_inc(mem))
diff --git a/arch/powerpc/kvm/book3s_64_vio_hv.c b/arch/powerpc/kvm/book3s_64_vio_hv.c
index 925fc316a104..5b298f5a1a14 100644
--- a/arch/powerpc/kvm/book3s_64_vio_hv.c
+++ b/arch/powerpc/kvm/book3s_64_vio_hv.c
@@ -279,7 +279,8 @@ static long kvmppc_rm_tce_iommu_do_map(struct kvm *kvm, struct iommu_table *tbl,
if (!mem)
return H_TOO_HARD;
- if (WARN_ON_ONCE_RM(mm_iommu_ua_to_hpa_rm(mem, ua, &hpa)))
+ if (WARN_ON_ONCE_RM(mm_iommu_ua_to_hpa_rm(mem, ua, tbl->it_page_shift,
+ &hpa)))
return H_HARDWARE;
pua = (void *) vmalloc_to_phys(pua);
@@ -469,7 +470,8 @@ long kvmppc_rm_h_put_tce_indirect(struct kvm_vcpu *vcpu,
mem = mm_iommu_lookup_rm(vcpu->kvm->mm, ua, IOMMU_PAGE_SIZE_4K);
if (mem)
- prereg = mm_iommu_ua_to_hpa_rm(mem, ua, &tces) == 0;
+ prereg = mm_iommu_ua_to_hpa_rm(mem, ua,
+ IOMMU_PAGE_SHIFT_4K, &tces) == 0;
}
if (!prereg) {
diff --git a/arch/powerpc/mm/mmu_context_iommu.c b/arch/powerpc/mm/mmu_context_iommu.c
index abb43646927a..a4ca57612558 100644
--- a/arch/powerpc/mm/mmu_context_iommu.c
+++ b/arch/powerpc/mm/mmu_context_iommu.c
@@ -19,6 +19,7 @@
#include <linux/hugetlb.h>
#include <linux/swap.h>
#include <asm/mmu_context.h>
+#include <asm/pte-walk.h>
static DEFINE_MUTEX(mem_list_mutex);
@@ -27,6 +28,7 @@ struct mm_iommu_table_group_mem_t {
struct rcu_head rcu;
unsigned long used;
atomic64_t mapped;
+ unsigned int pageshift;
u64 ua; /* userspace address */
u64 entries; /* number of entries in hpas[] */
u64 *hpas; /* vmalloc'ed */
@@ -125,6 +127,8 @@ long mm_iommu_get(struct mm_struct *mm, unsigned long ua, unsigned long entries,
{
struct mm_iommu_table_group_mem_t *mem;
long i, j, ret = 0, locked_entries = 0;
+ unsigned int pageshift;
+ unsigned long flags;
struct page *page = NULL;
mutex_lock(&mem_list_mutex);
@@ -159,6 +163,12 @@ long mm_iommu_get(struct mm_struct *mm, unsigned long ua, unsigned long entries,
goto unlock_exit;
}
+ /*
+ * For a starting point for a maximum page size calculation
+ * we use @ua and @entries natural alignment to allow IOMMU pages
+ * smaller than huge pages but still bigger than PAGE_SIZE.
+ */
+ mem->pageshift = __ffs(ua | (entries << PAGE_SHIFT));
mem->hpas = vzalloc(array_size(entries, sizeof(mem->hpas[0])));
if (!mem->hpas) {
kfree(mem);
@@ -199,6 +209,23 @@ long mm_iommu_get(struct mm_struct *mm, unsigned long ua, unsigned long entries,
}
}
populate:
+ pageshift = PAGE_SHIFT;
+ if (PageCompound(page)) {
+ pte_t *pte;
+ struct page *head = compound_head(page);
+ unsigned int compshift = compound_order(head);
+
+ local_irq_save(flags); /* disables as well */
+ pte = find_linux_pte(mm->pgd, ua, NULL, &pageshift);
+ local_irq_restore(flags);
+
+ /* Double check it is still the same pinned page */
+ if (pte && pte_page(*pte) == head &&
+ pageshift == compshift)
+ pageshift = max_t(unsigned int, pageshift,
+ PAGE_SHIFT);
+ }
+ mem->pageshift = min(mem->pageshift, pageshift);
mem->hpas[i] = page_to_pfn(page) << PAGE_SHIFT;
}
@@ -349,7 +376,7 @@ struct mm_iommu_table_group_mem_t *mm_iommu_find(struct mm_struct *mm,
EXPORT_SYMBOL_GPL(mm_iommu_find);
long mm_iommu_ua_to_hpa(struct mm_iommu_table_group_mem_t *mem,
- unsigned long ua, unsigned long *hpa)
+ unsigned long ua, unsigned int pageshift, unsigned long *hpa)
{
const long entry = (ua - mem->ua) >> PAGE_SHIFT;
u64 *va = &mem->hpas[entry];
@@ -357,6 +384,9 @@ long mm_iommu_ua_to_hpa(struct mm_iommu_table_group_mem_t *mem,
if (entry >= mem->entries)
return -EFAULT;
+ if (pageshift > mem->pageshift)
+ return -EFAULT;
+
*hpa = *va | (ua & ~PAGE_MASK);
return 0;
@@ -364,7 +394,7 @@ long mm_iommu_ua_to_hpa(struct mm_iommu_table_group_mem_t *mem,
EXPORT_SYMBOL_GPL(mm_iommu_ua_to_hpa);
long mm_iommu_ua_to_hpa_rm(struct mm_iommu_table_group_mem_t *mem,
- unsigned long ua, unsigned long *hpa)
+ unsigned long ua, unsigned int pageshift, unsigned long *hpa)
{
const long entry = (ua - mem->ua) >> PAGE_SHIFT;
void *va = &mem->hpas[entry];
@@ -373,6 +403,9 @@ long mm_iommu_ua_to_hpa_rm(struct mm_iommu_table_group_mem_t *mem,
if (entry >= mem->entries)
return -EFAULT;
+ if (pageshift > mem->pageshift)
+ return -EFAULT;
+
pa = (void *) vmalloc_to_phys(va);
if (!pa)
return -EFAULT;
diff --git a/drivers/vfio/vfio_iommu_spapr_tce.c b/drivers/vfio/vfio_iommu_spapr_tce.c
index 2da5f054257a..7cd63b0c1a46 100644
--- a/drivers/vfio/vfio_iommu_spapr_tce.c
+++ b/drivers/vfio/vfio_iommu_spapr_tce.c
@@ -467,7 +467,7 @@ static int tce_iommu_prereg_ua_to_hpa(struct tce_container *container,
if (!mem)
return -EINVAL;
- ret = mm_iommu_ua_to_hpa(mem, tce, phpa);
+ ret = mm_iommu_ua_to_hpa(mem, tce, shift, phpa);
if (ret)
return -EINVAL;
The patch below does not apply to the 4.17-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 <stable(a)vger.kernel.org>.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
>From 76fa4975f3ed12d15762bc979ca44078598ed8ee Mon Sep 17 00:00:00 2001
From: Alexey Kardashevskiy <aik(a)ozlabs.ru>
Date: Tue, 17 Jul 2018 17:19:13 +1000
Subject: [PATCH] KVM: PPC: Check if IOMMU page is contained in the pinned
physical page
A VM which has:
- a DMA capable device passed through to it (eg. network card);
- running a malicious kernel that ignores H_PUT_TCE failure;
- capability of using IOMMU pages bigger that physical pages
can create an IOMMU mapping that exposes (for example) 16MB of
the host physical memory to the device when only 64K was allocated to the VM.
The remaining 16MB - 64K will be some other content of host memory, possibly
including pages of the VM, but also pages of host kernel memory, host
programs or other VMs.
The attacking VM does not control the location of the page it can map,
and is only allowed to map as many pages as it has pages of RAM.
We already have a check in drivers/vfio/vfio_iommu_spapr_tce.c that
an IOMMU page is contained in the physical page so the PCI hardware won't
get access to unassigned host memory; however this check is missing in
the KVM fastpath (H_PUT_TCE accelerated code). We were lucky so far and
did not hit this yet as the very first time when the mapping happens
we do not have tbl::it_userspace allocated yet and fall back to
the userspace which in turn calls VFIO IOMMU driver, this fails and
the guest does not retry,
This stores the smallest preregistered page size in the preregistered
region descriptor and changes the mm_iommu_xxx API to check this against
the IOMMU page size.
This calculates maximum page size as a minimum of the natural region
alignment and compound page size. For the page shift this uses the shift
returned by find_linux_pte() which indicates how the page is mapped to
the current userspace - if the page is huge and this is not a zero, then
it is a leaf pte and the page is mapped within the range.
Fixes: 121f80ba68f1 ("KVM: PPC: VFIO: Add in-kernel acceleration for VFIO")
Cc: stable(a)vger.kernel.org # v4.12+
Signed-off-by: Alexey Kardashevskiy <aik(a)ozlabs.ru>
Reviewed-by: David Gibson <david(a)gibson.dropbear.id.au>
Signed-off-by: Michael Ellerman <mpe(a)ellerman.id.au>
diff --git a/arch/powerpc/include/asm/mmu_context.h b/arch/powerpc/include/asm/mmu_context.h
index 896efa559996..79d570cbf332 100644
--- a/arch/powerpc/include/asm/mmu_context.h
+++ b/arch/powerpc/include/asm/mmu_context.h
@@ -35,9 +35,9 @@ extern struct mm_iommu_table_group_mem_t *mm_iommu_lookup_rm(
extern struct mm_iommu_table_group_mem_t *mm_iommu_find(struct mm_struct *mm,
unsigned long ua, unsigned long entries);
extern long mm_iommu_ua_to_hpa(struct mm_iommu_table_group_mem_t *mem,
- unsigned long ua, unsigned long *hpa);
+ unsigned long ua, unsigned int pageshift, unsigned long *hpa);
extern long mm_iommu_ua_to_hpa_rm(struct mm_iommu_table_group_mem_t *mem,
- unsigned long ua, unsigned long *hpa);
+ unsigned long ua, unsigned int pageshift, unsigned long *hpa);
extern long mm_iommu_mapped_inc(struct mm_iommu_table_group_mem_t *mem);
extern void mm_iommu_mapped_dec(struct mm_iommu_table_group_mem_t *mem);
#endif
diff --git a/arch/powerpc/kvm/book3s_64_vio.c b/arch/powerpc/kvm/book3s_64_vio.c
index d066e37551ec..8c456fa691a5 100644
--- a/arch/powerpc/kvm/book3s_64_vio.c
+++ b/arch/powerpc/kvm/book3s_64_vio.c
@@ -449,7 +449,7 @@ long kvmppc_tce_iommu_do_map(struct kvm *kvm, struct iommu_table *tbl,
/* This only handles v2 IOMMU type, v1 is handled via ioctl() */
return H_TOO_HARD;
- if (WARN_ON_ONCE(mm_iommu_ua_to_hpa(mem, ua, &hpa)))
+ if (WARN_ON_ONCE(mm_iommu_ua_to_hpa(mem, ua, tbl->it_page_shift, &hpa)))
return H_HARDWARE;
if (mm_iommu_mapped_inc(mem))
diff --git a/arch/powerpc/kvm/book3s_64_vio_hv.c b/arch/powerpc/kvm/book3s_64_vio_hv.c
index 925fc316a104..5b298f5a1a14 100644
--- a/arch/powerpc/kvm/book3s_64_vio_hv.c
+++ b/arch/powerpc/kvm/book3s_64_vio_hv.c
@@ -279,7 +279,8 @@ static long kvmppc_rm_tce_iommu_do_map(struct kvm *kvm, struct iommu_table *tbl,
if (!mem)
return H_TOO_HARD;
- if (WARN_ON_ONCE_RM(mm_iommu_ua_to_hpa_rm(mem, ua, &hpa)))
+ if (WARN_ON_ONCE_RM(mm_iommu_ua_to_hpa_rm(mem, ua, tbl->it_page_shift,
+ &hpa)))
return H_HARDWARE;
pua = (void *) vmalloc_to_phys(pua);
@@ -469,7 +470,8 @@ long kvmppc_rm_h_put_tce_indirect(struct kvm_vcpu *vcpu,
mem = mm_iommu_lookup_rm(vcpu->kvm->mm, ua, IOMMU_PAGE_SIZE_4K);
if (mem)
- prereg = mm_iommu_ua_to_hpa_rm(mem, ua, &tces) == 0;
+ prereg = mm_iommu_ua_to_hpa_rm(mem, ua,
+ IOMMU_PAGE_SHIFT_4K, &tces) == 0;
}
if (!prereg) {
diff --git a/arch/powerpc/mm/mmu_context_iommu.c b/arch/powerpc/mm/mmu_context_iommu.c
index abb43646927a..a4ca57612558 100644
--- a/arch/powerpc/mm/mmu_context_iommu.c
+++ b/arch/powerpc/mm/mmu_context_iommu.c
@@ -19,6 +19,7 @@
#include <linux/hugetlb.h>
#include <linux/swap.h>
#include <asm/mmu_context.h>
+#include <asm/pte-walk.h>
static DEFINE_MUTEX(mem_list_mutex);
@@ -27,6 +28,7 @@ struct mm_iommu_table_group_mem_t {
struct rcu_head rcu;
unsigned long used;
atomic64_t mapped;
+ unsigned int pageshift;
u64 ua; /* userspace address */
u64 entries; /* number of entries in hpas[] */
u64 *hpas; /* vmalloc'ed */
@@ -125,6 +127,8 @@ long mm_iommu_get(struct mm_struct *mm, unsigned long ua, unsigned long entries,
{
struct mm_iommu_table_group_mem_t *mem;
long i, j, ret = 0, locked_entries = 0;
+ unsigned int pageshift;
+ unsigned long flags;
struct page *page = NULL;
mutex_lock(&mem_list_mutex);
@@ -159,6 +163,12 @@ long mm_iommu_get(struct mm_struct *mm, unsigned long ua, unsigned long entries,
goto unlock_exit;
}
+ /*
+ * For a starting point for a maximum page size calculation
+ * we use @ua and @entries natural alignment to allow IOMMU pages
+ * smaller than huge pages but still bigger than PAGE_SIZE.
+ */
+ mem->pageshift = __ffs(ua | (entries << PAGE_SHIFT));
mem->hpas = vzalloc(array_size(entries, sizeof(mem->hpas[0])));
if (!mem->hpas) {
kfree(mem);
@@ -199,6 +209,23 @@ long mm_iommu_get(struct mm_struct *mm, unsigned long ua, unsigned long entries,
}
}
populate:
+ pageshift = PAGE_SHIFT;
+ if (PageCompound(page)) {
+ pte_t *pte;
+ struct page *head = compound_head(page);
+ unsigned int compshift = compound_order(head);
+
+ local_irq_save(flags); /* disables as well */
+ pte = find_linux_pte(mm->pgd, ua, NULL, &pageshift);
+ local_irq_restore(flags);
+
+ /* Double check it is still the same pinned page */
+ if (pte && pte_page(*pte) == head &&
+ pageshift == compshift)
+ pageshift = max_t(unsigned int, pageshift,
+ PAGE_SHIFT);
+ }
+ mem->pageshift = min(mem->pageshift, pageshift);
mem->hpas[i] = page_to_pfn(page) << PAGE_SHIFT;
}
@@ -349,7 +376,7 @@ struct mm_iommu_table_group_mem_t *mm_iommu_find(struct mm_struct *mm,
EXPORT_SYMBOL_GPL(mm_iommu_find);
long mm_iommu_ua_to_hpa(struct mm_iommu_table_group_mem_t *mem,
- unsigned long ua, unsigned long *hpa)
+ unsigned long ua, unsigned int pageshift, unsigned long *hpa)
{
const long entry = (ua - mem->ua) >> PAGE_SHIFT;
u64 *va = &mem->hpas[entry];
@@ -357,6 +384,9 @@ long mm_iommu_ua_to_hpa(struct mm_iommu_table_group_mem_t *mem,
if (entry >= mem->entries)
return -EFAULT;
+ if (pageshift > mem->pageshift)
+ return -EFAULT;
+
*hpa = *va | (ua & ~PAGE_MASK);
return 0;
@@ -364,7 +394,7 @@ long mm_iommu_ua_to_hpa(struct mm_iommu_table_group_mem_t *mem,
EXPORT_SYMBOL_GPL(mm_iommu_ua_to_hpa);
long mm_iommu_ua_to_hpa_rm(struct mm_iommu_table_group_mem_t *mem,
- unsigned long ua, unsigned long *hpa)
+ unsigned long ua, unsigned int pageshift, unsigned long *hpa)
{
const long entry = (ua - mem->ua) >> PAGE_SHIFT;
void *va = &mem->hpas[entry];
@@ -373,6 +403,9 @@ long mm_iommu_ua_to_hpa_rm(struct mm_iommu_table_group_mem_t *mem,
if (entry >= mem->entries)
return -EFAULT;
+ if (pageshift > mem->pageshift)
+ return -EFAULT;
+
pa = (void *) vmalloc_to_phys(va);
if (!pa)
return -EFAULT;
diff --git a/drivers/vfio/vfio_iommu_spapr_tce.c b/drivers/vfio/vfio_iommu_spapr_tce.c
index 2da5f054257a..7cd63b0c1a46 100644
--- a/drivers/vfio/vfio_iommu_spapr_tce.c
+++ b/drivers/vfio/vfio_iommu_spapr_tce.c
@@ -467,7 +467,7 @@ static int tce_iommu_prereg_ua_to_hpa(struct tce_container *container,
if (!mem)
return -EINVAL;
- ret = mm_iommu_ua_to_hpa(mem, tce, phpa);
+ ret = mm_iommu_ua_to_hpa(mem, tce, shift, phpa);
if (ret)
return -EINVAL;
The patch below does not apply to the 4.4-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 <stable(a)vger.kernel.org>.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
>From bd3599a0e142cd73edd3b6801068ac3f48ac771a Mon Sep 17 00:00:00 2001
From: Filipe Manana <fdmanana(a)suse.com>
Date: Thu, 12 Jul 2018 01:36:43 +0100
Subject: [PATCH] Btrfs: fix file data corruption after cloning a range and
fsync
When we clone a range into a file we can end up dropping existing
extent maps (or trimming them) and replacing them with new ones if the
range to be cloned overlaps with a range in the destination inode.
When that happens we add the new extent maps to the list of modified
extents in the inode's extent map tree, so that a "fast" fsync (the flag
BTRFS_INODE_NEEDS_FULL_SYNC not set in the inode) will see the extent maps
and log corresponding extent items. However, at the end of range cloning
operation we do truncate all the pages in the affected range (in order to
ensure future reads will not get stale data). Sometimes this truncation
will release the corresponding extent maps besides the pages from the page
cache. If this happens, then a "fast" fsync operation will miss logging
some extent items, because it relies exclusively on the extent maps being
present in the inode's extent tree, leading to data loss/corruption if
the fsync ends up using the same transaction used by the clone operation
(that transaction was not committed in the meanwhile). An extent map is
released through the callback btrfs_invalidatepage(), which gets called by
truncate_inode_pages_range(), and it calls __btrfs_releasepage(). The
later ends up calling try_release_extent_mapping() which will release the
extent map if some conditions are met, like the file size being greater
than 16Mb, gfp flags allow blocking and the range not being locked (which
is the case during the clone operation) nor being the extent map flagged
as pinned (also the case for cloning).
The following example, turned into a test for fstests, reproduces the
issue:
$ mkfs.btrfs -f /dev/sdb
$ mount /dev/sdb /mnt
$ xfs_io -f -c "pwrite -S 0x18 9000K 6908K" /mnt/foo
$ xfs_io -f -c "pwrite -S 0x20 2572K 156K" /mnt/bar
$ xfs_io -c "fsync" /mnt/bar
# reflink destination offset corresponds to the size of file bar,
# 2728Kb minus 4Kb.
$ xfs_io -c ""reflink ${SCRATCH_MNT}/foo 0 2724K 15908K" /mnt/bar
$ xfs_io -c "fsync" /mnt/bar
$ md5sum /mnt/bar
95a95813a8c2abc9aa75a6c2914a077e /mnt/bar
<power fail>
$ mount /dev/sdb /mnt
$ md5sum /mnt/bar
207fd8d0b161be8a84b945f0df8d5f8d /mnt/bar
# digest should be 95a95813a8c2abc9aa75a6c2914a077e like before the
# power failure
In the above example, the destination offset of the clone operation
corresponds to the size of the "bar" file minus 4Kb. So during the clone
operation, the extent map covering the range from 2572Kb to 2728Kb gets
trimmed so that it ends at offset 2724Kb, and a new extent map covering
the range from 2724Kb to 11724Kb is created. So at the end of the clone
operation when we ask to truncate the pages in the range from 2724Kb to
2724Kb + 15908Kb, the page invalidation callback ends up removing the new
extent map (through try_release_extent_mapping()) when the page at offset
2724Kb is passed to that callback.
Fix this by setting the bit BTRFS_INODE_NEEDS_FULL_SYNC whenever an extent
map is removed at try_release_extent_mapping(), forcing the next fsync to
search for modified extents in the fs/subvolume tree instead of relying on
the presence of extent maps in memory. This way we can continue doing a
"fast" fsync if the destination range of a clone operation does not
overlap with an existing range or if any of the criteria necessary to
remove an extent map at try_release_extent_mapping() is not met (file
size not bigger then 16Mb or gfp flags do not allow blocking).
CC: stable(a)vger.kernel.org # 3.16+
Signed-off-by: Filipe Manana <fdmanana(a)suse.com>
Signed-off-by: David Sterba <dsterba(a)suse.com>
diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c
index 1aa91d57404a..8fd86e29085f 100644
--- a/fs/btrfs/extent_io.c
+++ b/fs/btrfs/extent_io.c
@@ -4241,8 +4241,9 @@ int try_release_extent_mapping(struct page *page, gfp_t mask)
struct extent_map *em;
u64 start = page_offset(page);
u64 end = start + PAGE_SIZE - 1;
- struct extent_io_tree *tree = &BTRFS_I(page->mapping->host)->io_tree;
- struct extent_map_tree *map = &BTRFS_I(page->mapping->host)->extent_tree;
+ struct btrfs_inode *btrfs_inode = BTRFS_I(page->mapping->host);
+ struct extent_io_tree *tree = &btrfs_inode->io_tree;
+ struct extent_map_tree *map = &btrfs_inode->extent_tree;
if (gfpflags_allow_blocking(mask) &&
page->mapping->host->i_size > SZ_16M) {
@@ -4265,6 +4266,8 @@ int try_release_extent_mapping(struct page *page, gfp_t mask)
extent_map_end(em) - 1,
EXTENT_LOCKED | EXTENT_WRITEBACK,
0, NULL)) {
+ set_bit(BTRFS_INODE_NEEDS_FULL_SYNC,
+ &btrfs_inode->runtime_flags);
remove_extent_mapping(map, em);
/* once for the rb tree */
free_extent_map(em);
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 <stable(a)vger.kernel.org>.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
>From bd3599a0e142cd73edd3b6801068ac3f48ac771a Mon Sep 17 00:00:00 2001
From: Filipe Manana <fdmanana(a)suse.com>
Date: Thu, 12 Jul 2018 01:36:43 +0100
Subject: [PATCH] Btrfs: fix file data corruption after cloning a range and
fsync
When we clone a range into a file we can end up dropping existing
extent maps (or trimming them) and replacing them with new ones if the
range to be cloned overlaps with a range in the destination inode.
When that happens we add the new extent maps to the list of modified
extents in the inode's extent map tree, so that a "fast" fsync (the flag
BTRFS_INODE_NEEDS_FULL_SYNC not set in the inode) will see the extent maps
and log corresponding extent items. However, at the end of range cloning
operation we do truncate all the pages in the affected range (in order to
ensure future reads will not get stale data). Sometimes this truncation
will release the corresponding extent maps besides the pages from the page
cache. If this happens, then a "fast" fsync operation will miss logging
some extent items, because it relies exclusively on the extent maps being
present in the inode's extent tree, leading to data loss/corruption if
the fsync ends up using the same transaction used by the clone operation
(that transaction was not committed in the meanwhile). An extent map is
released through the callback btrfs_invalidatepage(), which gets called by
truncate_inode_pages_range(), and it calls __btrfs_releasepage(). The
later ends up calling try_release_extent_mapping() which will release the
extent map if some conditions are met, like the file size being greater
than 16Mb, gfp flags allow blocking and the range not being locked (which
is the case during the clone operation) nor being the extent map flagged
as pinned (also the case for cloning).
The following example, turned into a test for fstests, reproduces the
issue:
$ mkfs.btrfs -f /dev/sdb
$ mount /dev/sdb /mnt
$ xfs_io -f -c "pwrite -S 0x18 9000K 6908K" /mnt/foo
$ xfs_io -f -c "pwrite -S 0x20 2572K 156K" /mnt/bar
$ xfs_io -c "fsync" /mnt/bar
# reflink destination offset corresponds to the size of file bar,
# 2728Kb minus 4Kb.
$ xfs_io -c ""reflink ${SCRATCH_MNT}/foo 0 2724K 15908K" /mnt/bar
$ xfs_io -c "fsync" /mnt/bar
$ md5sum /mnt/bar
95a95813a8c2abc9aa75a6c2914a077e /mnt/bar
<power fail>
$ mount /dev/sdb /mnt
$ md5sum /mnt/bar
207fd8d0b161be8a84b945f0df8d5f8d /mnt/bar
# digest should be 95a95813a8c2abc9aa75a6c2914a077e like before the
# power failure
In the above example, the destination offset of the clone operation
corresponds to the size of the "bar" file minus 4Kb. So during the clone
operation, the extent map covering the range from 2572Kb to 2728Kb gets
trimmed so that it ends at offset 2724Kb, and a new extent map covering
the range from 2724Kb to 11724Kb is created. So at the end of the clone
operation when we ask to truncate the pages in the range from 2724Kb to
2724Kb + 15908Kb, the page invalidation callback ends up removing the new
extent map (through try_release_extent_mapping()) when the page at offset
2724Kb is passed to that callback.
Fix this by setting the bit BTRFS_INODE_NEEDS_FULL_SYNC whenever an extent
map is removed at try_release_extent_mapping(), forcing the next fsync to
search for modified extents in the fs/subvolume tree instead of relying on
the presence of extent maps in memory. This way we can continue doing a
"fast" fsync if the destination range of a clone operation does not
overlap with an existing range or if any of the criteria necessary to
remove an extent map at try_release_extent_mapping() is not met (file
size not bigger then 16Mb or gfp flags do not allow blocking).
CC: stable(a)vger.kernel.org # 3.16+
Signed-off-by: Filipe Manana <fdmanana(a)suse.com>
Signed-off-by: David Sterba <dsterba(a)suse.com>
diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c
index 1aa91d57404a..8fd86e29085f 100644
--- a/fs/btrfs/extent_io.c
+++ b/fs/btrfs/extent_io.c
@@ -4241,8 +4241,9 @@ int try_release_extent_mapping(struct page *page, gfp_t mask)
struct extent_map *em;
u64 start = page_offset(page);
u64 end = start + PAGE_SIZE - 1;
- struct extent_io_tree *tree = &BTRFS_I(page->mapping->host)->io_tree;
- struct extent_map_tree *map = &BTRFS_I(page->mapping->host)->extent_tree;
+ struct btrfs_inode *btrfs_inode = BTRFS_I(page->mapping->host);
+ struct extent_io_tree *tree = &btrfs_inode->io_tree;
+ struct extent_map_tree *map = &btrfs_inode->extent_tree;
if (gfpflags_allow_blocking(mask) &&
page->mapping->host->i_size > SZ_16M) {
@@ -4265,6 +4266,8 @@ int try_release_extent_mapping(struct page *page, gfp_t mask)
extent_map_end(em) - 1,
EXTENT_LOCKED | EXTENT_WRITEBACK,
0, NULL)) {
+ set_bit(BTRFS_INODE_NEEDS_FULL_SYNC,
+ &btrfs_inode->runtime_flags);
remove_extent_mapping(map, em);
/* once for the rb tree */
free_extent_map(em);
The patch below does not apply to the 4.17-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 <stable(a)vger.kernel.org>.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
>From bd3599a0e142cd73edd3b6801068ac3f48ac771a Mon Sep 17 00:00:00 2001
From: Filipe Manana <fdmanana(a)suse.com>
Date: Thu, 12 Jul 2018 01:36:43 +0100
Subject: [PATCH] Btrfs: fix file data corruption after cloning a range and
fsync
When we clone a range into a file we can end up dropping existing
extent maps (or trimming them) and replacing them with new ones if the
range to be cloned overlaps with a range in the destination inode.
When that happens we add the new extent maps to the list of modified
extents in the inode's extent map tree, so that a "fast" fsync (the flag
BTRFS_INODE_NEEDS_FULL_SYNC not set in the inode) will see the extent maps
and log corresponding extent items. However, at the end of range cloning
operation we do truncate all the pages in the affected range (in order to
ensure future reads will not get stale data). Sometimes this truncation
will release the corresponding extent maps besides the pages from the page
cache. If this happens, then a "fast" fsync operation will miss logging
some extent items, because it relies exclusively on the extent maps being
present in the inode's extent tree, leading to data loss/corruption if
the fsync ends up using the same transaction used by the clone operation
(that transaction was not committed in the meanwhile). An extent map is
released through the callback btrfs_invalidatepage(), which gets called by
truncate_inode_pages_range(), and it calls __btrfs_releasepage(). The
later ends up calling try_release_extent_mapping() which will release the
extent map if some conditions are met, like the file size being greater
than 16Mb, gfp flags allow blocking and the range not being locked (which
is the case during the clone operation) nor being the extent map flagged
as pinned (also the case for cloning).
The following example, turned into a test for fstests, reproduces the
issue:
$ mkfs.btrfs -f /dev/sdb
$ mount /dev/sdb /mnt
$ xfs_io -f -c "pwrite -S 0x18 9000K 6908K" /mnt/foo
$ xfs_io -f -c "pwrite -S 0x20 2572K 156K" /mnt/bar
$ xfs_io -c "fsync" /mnt/bar
# reflink destination offset corresponds to the size of file bar,
# 2728Kb minus 4Kb.
$ xfs_io -c ""reflink ${SCRATCH_MNT}/foo 0 2724K 15908K" /mnt/bar
$ xfs_io -c "fsync" /mnt/bar
$ md5sum /mnt/bar
95a95813a8c2abc9aa75a6c2914a077e /mnt/bar
<power fail>
$ mount /dev/sdb /mnt
$ md5sum /mnt/bar
207fd8d0b161be8a84b945f0df8d5f8d /mnt/bar
# digest should be 95a95813a8c2abc9aa75a6c2914a077e like before the
# power failure
In the above example, the destination offset of the clone operation
corresponds to the size of the "bar" file minus 4Kb. So during the clone
operation, the extent map covering the range from 2572Kb to 2728Kb gets
trimmed so that it ends at offset 2724Kb, and a new extent map covering
the range from 2724Kb to 11724Kb is created. So at the end of the clone
operation when we ask to truncate the pages in the range from 2724Kb to
2724Kb + 15908Kb, the page invalidation callback ends up removing the new
extent map (through try_release_extent_mapping()) when the page at offset
2724Kb is passed to that callback.
Fix this by setting the bit BTRFS_INODE_NEEDS_FULL_SYNC whenever an extent
map is removed at try_release_extent_mapping(), forcing the next fsync to
search for modified extents in the fs/subvolume tree instead of relying on
the presence of extent maps in memory. This way we can continue doing a
"fast" fsync if the destination range of a clone operation does not
overlap with an existing range or if any of the criteria necessary to
remove an extent map at try_release_extent_mapping() is not met (file
size not bigger then 16Mb or gfp flags do not allow blocking).
CC: stable(a)vger.kernel.org # 3.16+
Signed-off-by: Filipe Manana <fdmanana(a)suse.com>
Signed-off-by: David Sterba <dsterba(a)suse.com>
diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c
index 1aa91d57404a..8fd86e29085f 100644
--- a/fs/btrfs/extent_io.c
+++ b/fs/btrfs/extent_io.c
@@ -4241,8 +4241,9 @@ int try_release_extent_mapping(struct page *page, gfp_t mask)
struct extent_map *em;
u64 start = page_offset(page);
u64 end = start + PAGE_SIZE - 1;
- struct extent_io_tree *tree = &BTRFS_I(page->mapping->host)->io_tree;
- struct extent_map_tree *map = &BTRFS_I(page->mapping->host)->extent_tree;
+ struct btrfs_inode *btrfs_inode = BTRFS_I(page->mapping->host);
+ struct extent_io_tree *tree = &btrfs_inode->io_tree;
+ struct extent_map_tree *map = &btrfs_inode->extent_tree;
if (gfpflags_allow_blocking(mask) &&
page->mapping->host->i_size > SZ_16M) {
@@ -4265,6 +4266,8 @@ int try_release_extent_mapping(struct page *page, gfp_t mask)
extent_map_end(em) - 1,
EXTENT_LOCKED | EXTENT_WRITEBACK,
0, NULL)) {
+ set_bit(BTRFS_INODE_NEEDS_FULL_SYNC,
+ &btrfs_inode->runtime_flags);
remove_extent_mapping(map, em);
/* once for the rb tree */
free_extent_map(em);
The patch below does not apply to the 4.4-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 <stable(a)vger.kernel.org>.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
>From 95d6c0857e54b788982746071130d822a795026b Mon Sep 17 00:00:00 2001
From: "Rafael J. Wysocki" <rafael.j.wysocki(a)intel.com>
Date: Wed, 18 Jul 2018 13:38:37 +0200
Subject: [PATCH] cpufreq: intel_pstate: Register when ACPI PCCH is present
Currently, intel_pstate doesn't register if _PSS is not present on
HP Proliant systems, because it expects the firmware to take over
CPU performance scaling in that case. However, if ACPI PCCH is
present, the firmware expects the kernel to use it for CPU
performance scaling and the pcc-cpufreq driver is loaded for that.
Unfortunately, the firmware interface used by that driver is not
scalable for fundamental reasons, so pcc-cpufreq is way suboptimal
on systems with more than just a few CPUs. In fact, it is better to
avoid using it at all.
For this reason, modify intel_pstate to look for ACPI PCCH if _PSS
is not present and register if it is there. Also prevent the
pcc-cpufreq driver from trying to initialize itself if intel_pstate
has been registered already.
Fixes: fbbcdc0744da (intel_pstate: skip the driver if ACPI has power mgmt option)
Reported-by: Andreas Herrmann <aherrmann(a)suse.com>
Reviewed-by: Andreas Herrmann <aherrmann(a)suse.com>
Acked-by: Srinivas Pandruvada <srinivas.pandruvada(a)linux.intel.com>
Tested-by: Andreas Herrmann <aherrmann(a)suse.com>
Cc: 4.16+ <stable(a)vger.kernel.org> # 4.16+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki(a)intel.com>
diff --git a/drivers/cpufreq/intel_pstate.c b/drivers/cpufreq/intel_pstate.c
index ece120da3353..3c3971256130 100644
--- a/drivers/cpufreq/intel_pstate.c
+++ b/drivers/cpufreq/intel_pstate.c
@@ -2394,6 +2394,18 @@ static bool __init intel_pstate_no_acpi_pss(void)
return true;
}
+static bool __init intel_pstate_no_acpi_pcch(void)
+{
+ acpi_status status;
+ acpi_handle handle;
+
+ status = acpi_get_handle(NULL, "\\_SB", &handle);
+ if (ACPI_FAILURE(status))
+ return true;
+
+ return !acpi_has_method(handle, "PCCH");
+}
+
static bool __init intel_pstate_has_acpi_ppc(void)
{
int i;
@@ -2453,7 +2465,10 @@ static bool __init intel_pstate_platform_pwr_mgmt_exists(void)
switch (plat_info[idx].data) {
case PSS:
- return intel_pstate_no_acpi_pss();
+ if (!intel_pstate_no_acpi_pss())
+ return false;
+
+ return intel_pstate_no_acpi_pcch();
case PPC:
return intel_pstate_has_acpi_ppc() && !force_load;
}
diff --git a/drivers/cpufreq/pcc-cpufreq.c b/drivers/cpufreq/pcc-cpufreq.c
index 3f0ce2ae35ee..0c56c9759672 100644
--- a/drivers/cpufreq/pcc-cpufreq.c
+++ b/drivers/cpufreq/pcc-cpufreq.c
@@ -580,6 +580,10 @@ static int __init pcc_cpufreq_init(void)
{
int ret;
+ /* Skip initialization if another cpufreq driver is there. */
+ if (cpufreq_get_current_driver())
+ return 0;
+
if (acpi_disabled)
return 0;
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 <stable(a)vger.kernel.org>.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
>From 95d6c0857e54b788982746071130d822a795026b Mon Sep 17 00:00:00 2001
From: "Rafael J. Wysocki" <rafael.j.wysocki(a)intel.com>
Date: Wed, 18 Jul 2018 13:38:37 +0200
Subject: [PATCH] cpufreq: intel_pstate: Register when ACPI PCCH is present
Currently, intel_pstate doesn't register if _PSS is not present on
HP Proliant systems, because it expects the firmware to take over
CPU performance scaling in that case. However, if ACPI PCCH is
present, the firmware expects the kernel to use it for CPU
performance scaling and the pcc-cpufreq driver is loaded for that.
Unfortunately, the firmware interface used by that driver is not
scalable for fundamental reasons, so pcc-cpufreq is way suboptimal
on systems with more than just a few CPUs. In fact, it is better to
avoid using it at all.
For this reason, modify intel_pstate to look for ACPI PCCH if _PSS
is not present and register if it is there. Also prevent the
pcc-cpufreq driver from trying to initialize itself if intel_pstate
has been registered already.
Fixes: fbbcdc0744da (intel_pstate: skip the driver if ACPI has power mgmt option)
Reported-by: Andreas Herrmann <aherrmann(a)suse.com>
Reviewed-by: Andreas Herrmann <aherrmann(a)suse.com>
Acked-by: Srinivas Pandruvada <srinivas.pandruvada(a)linux.intel.com>
Tested-by: Andreas Herrmann <aherrmann(a)suse.com>
Cc: 4.16+ <stable(a)vger.kernel.org> # 4.16+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki(a)intel.com>
diff --git a/drivers/cpufreq/intel_pstate.c b/drivers/cpufreq/intel_pstate.c
index ece120da3353..3c3971256130 100644
--- a/drivers/cpufreq/intel_pstate.c
+++ b/drivers/cpufreq/intel_pstate.c
@@ -2394,6 +2394,18 @@ static bool __init intel_pstate_no_acpi_pss(void)
return true;
}
+static bool __init intel_pstate_no_acpi_pcch(void)
+{
+ acpi_status status;
+ acpi_handle handle;
+
+ status = acpi_get_handle(NULL, "\\_SB", &handle);
+ if (ACPI_FAILURE(status))
+ return true;
+
+ return !acpi_has_method(handle, "PCCH");
+}
+
static bool __init intel_pstate_has_acpi_ppc(void)
{
int i;
@@ -2453,7 +2465,10 @@ static bool __init intel_pstate_platform_pwr_mgmt_exists(void)
switch (plat_info[idx].data) {
case PSS:
- return intel_pstate_no_acpi_pss();
+ if (!intel_pstate_no_acpi_pss())
+ return false;
+
+ return intel_pstate_no_acpi_pcch();
case PPC:
return intel_pstate_has_acpi_ppc() && !force_load;
}
diff --git a/drivers/cpufreq/pcc-cpufreq.c b/drivers/cpufreq/pcc-cpufreq.c
index 3f0ce2ae35ee..0c56c9759672 100644
--- a/drivers/cpufreq/pcc-cpufreq.c
+++ b/drivers/cpufreq/pcc-cpufreq.c
@@ -580,6 +580,10 @@ static int __init pcc_cpufreq_init(void)
{
int ret;
+ /* Skip initialization if another cpufreq driver is there. */
+ if (cpufreq_get_current_driver())
+ return 0;
+
if (acpi_disabled)
return 0;
Commit b1092c9af9ed ("bcache: allow quick writeback when backing idle")
allows the writeback rate to be faster if there is no I/O request on a
bcache device. It works well if there is only one bcache device attached
to the cache set. If there are many bcache devices attached to a cache
set, it may introduce performance regression because multiple faster
writeback threads of the idle bcache devices will compete the btree level
locks with the bcache device who have I/O requests coming.
This patch fixes the above issue by only permitting fast writebac when
all bcache devices attached on the cache set are idle. And if one of the
bcache devices has new I/O request coming, minimized all writeback
throughput immediately and let PI controller __update_writeback_rate()
to decide the upcoming writeback rate for each bcache device.
Also when all bcache devices are idle, limited wrieback rate to a small
number is wast of thoughput, especially when backing devices are slower
non-rotation devices (e.g. SATA SSD). This patch sets a max writeback
rate for each backing device if the whole cache set is idle. A faster
writeback rate in idle time means new I/Os may have more available space
for dirty data, and people may observe a better write performance then.
Please note bcache may change its cache mode in run time, and this patch
still works if the cache mode is switched from writeback mode and there
is still dirty data on cache.
Fixes: Commit b1092c9af9ed ("bcache: allow quick writeback when backing idle")
Cc: stable(a)vger.kernel.org #4.16+
Signed-off-by: Coly Li <colyli(a)suse.de>
Cc: Michael Lyle <mlyle(a)lyle.org>
---
drivers/md/bcache/bcache.h | 9 +---
drivers/md/bcache/request.c | 42 ++++++++++++++-
drivers/md/bcache/sysfs.c | 14 +++--
drivers/md/bcache/util.c | 2 +-
drivers/md/bcache/util.h | 2 +-
drivers/md/bcache/writeback.c | 98 +++++++++++++++++++++++++----------
6 files changed, 126 insertions(+), 41 deletions(-)
diff --git a/drivers/md/bcache/bcache.h b/drivers/md/bcache/bcache.h
index d6bf294f3907..f7451e8be03c 100644
--- a/drivers/md/bcache/bcache.h
+++ b/drivers/md/bcache/bcache.h
@@ -328,13 +328,6 @@ struct cached_dev {
*/
atomic_t has_dirty;
- /*
- * Set to zero by things that touch the backing volume-- except
- * writeback. Incremented by writeback. Used to determine when to
- * accelerate idle writeback.
- */
- atomic_t backing_idle;
-
struct bch_ratelimit writeback_rate;
struct delayed_work writeback_rate_update;
@@ -514,6 +507,8 @@ struct cache_set {
struct cache_accounting accounting;
unsigned long flags;
+ atomic_t idle_counter;
+ atomic_t at_max_writeback_rate;
struct cache_sb sb;
diff --git a/drivers/md/bcache/request.c b/drivers/md/bcache/request.c
index ae67f5fa8047..fe45f561a054 100644
--- a/drivers/md/bcache/request.c
+++ b/drivers/md/bcache/request.c
@@ -1104,6 +1104,34 @@ static void detached_dev_do_request(struct bcache_device *d, struct bio *bio)
/* Cached devices - read & write stuff */
+static void quit_max_writeback_rate(struct cache_set *c)
+{
+ int i;
+ struct bcache_device *d;
+ struct cached_dev *dc;
+
+ mutex_lock(&bch_register_lock);
+
+ for (i = 0; i < c->devices_max_used; i++) {
+ if (!c->devices[i])
+ continue;
+
+ if (UUID_FLASH_ONLY(&c->uuids[i]))
+ continue;
+
+ d = c->devices[i];
+ dc = container_of(d, struct cached_dev, disk);
+ /*
+ * set writeback rate to default minimum value,
+ * then let update_writeback_rate() to decide the
+ * upcoming rate.
+ */
+ atomic64_set(&dc->writeback_rate.rate, 1);
+ }
+
+ mutex_unlock(&bch_register_lock);
+}
+
static blk_qc_t cached_dev_make_request(struct request_queue *q,
struct bio *bio)
{
@@ -1119,7 +1147,19 @@ static blk_qc_t cached_dev_make_request(struct request_queue *q,
return BLK_QC_T_NONE;
}
- atomic_set(&dc->backing_idle, 0);
+ if (d->c) {
+ atomic_set(&d->c->idle_counter, 0);
+ /*
+ * If at_max_writeback_rate of cache set is true and new I/O
+ * comes, quit max writeback rate of all cached devices
+ * attached to this cache set, and set at_max_writeback_rate
+ * to false.
+ */
+ if (unlikely(atomic_read(&d->c->at_max_writeback_rate) == 1)) {
+ atomic_set(&d->c->at_max_writeback_rate, 0);
+ quit_max_writeback_rate(d->c);
+ }
+ }
generic_start_io_acct(q, rw, bio_sectors(bio), &d->disk->part0);
bio_set_dev(bio, dc->bdev);
diff --git a/drivers/md/bcache/sysfs.c b/drivers/md/bcache/sysfs.c
index 225b15aa0340..d719021bff81 100644
--- a/drivers/md/bcache/sysfs.c
+++ b/drivers/md/bcache/sysfs.c
@@ -170,7 +170,8 @@ SHOW(__bch_cached_dev)
var_printf(writeback_running, "%i");
var_print(writeback_delay);
var_print(writeback_percent);
- sysfs_hprint(writeback_rate, dc->writeback_rate.rate << 9);
+ sysfs_hprint(writeback_rate,
+ atomic64_read(&dc->writeback_rate.rate) << 9);
sysfs_hprint(io_errors, atomic_read(&dc->io_errors));
sysfs_printf(io_error_limit, "%i", dc->error_limit);
sysfs_printf(io_disable, "%i", dc->io_disable);
@@ -188,7 +189,8 @@ SHOW(__bch_cached_dev)
char change[20];
s64 next_io;
- bch_hprint(rate, dc->writeback_rate.rate << 9);
+ bch_hprint(rate,
+ atomic64_read(&dc->writeback_rate.rate) << 9);
bch_hprint(dirty, bcache_dev_sectors_dirty(&dc->disk) << 9);
bch_hprint(target, dc->writeback_rate_target << 9);
bch_hprint(proportional,dc->writeback_rate_proportional << 9);
@@ -255,8 +257,12 @@ STORE(__cached_dev)
sysfs_strtoul_clamp(writeback_percent, dc->writeback_percent, 0, 40);
- sysfs_strtoul_clamp(writeback_rate,
- dc->writeback_rate.rate, 1, INT_MAX);
+ if (attr == &sysfs_writeback_rate) {
+ int v;
+
+ sysfs_strtoul_clamp(writeback_rate, v, 1, INT_MAX);
+ atomic64_set(&dc->writeback_rate.rate, v);
+ }
sysfs_strtoul_clamp(writeback_rate_update_seconds,
dc->writeback_rate_update_seconds,
diff --git a/drivers/md/bcache/util.c b/drivers/md/bcache/util.c
index fc479b026d6d..84f90c3d996d 100644
--- a/drivers/md/bcache/util.c
+++ b/drivers/md/bcache/util.c
@@ -200,7 +200,7 @@ uint64_t bch_next_delay(struct bch_ratelimit *d, uint64_t done)
{
uint64_t now = local_clock();
- d->next += div_u64(done * NSEC_PER_SEC, d->rate);
+ d->next += div_u64(done * NSEC_PER_SEC, atomic64_read(&d->rate));
/* Bound the time. Don't let us fall further than 2 seconds behind
* (this prevents unnecessary backlog that would make it impossible
diff --git a/drivers/md/bcache/util.h b/drivers/md/bcache/util.h
index cced87f8eb27..7e17f32ab563 100644
--- a/drivers/md/bcache/util.h
+++ b/drivers/md/bcache/util.h
@@ -442,7 +442,7 @@ struct bch_ratelimit {
* Rate at which we want to do work, in units per second
* The units here correspond to the units passed to bch_next_delay()
*/
- uint32_t rate;
+ atomic64_t rate;
};
static inline void bch_ratelimit_reset(struct bch_ratelimit *d)
diff --git a/drivers/md/bcache/writeback.c b/drivers/md/bcache/writeback.c
index ad45ebe1a74b..72059f910230 100644
--- a/drivers/md/bcache/writeback.c
+++ b/drivers/md/bcache/writeback.c
@@ -49,6 +49,63 @@ static uint64_t __calc_target_rate(struct cached_dev *dc)
return (cache_dirty_target * bdev_share) >> WRITEBACK_SHARE_SHIFT;
}
+static bool set_at_max_writeback_rate(struct cache_set *c,
+ struct cached_dev *dc)
+{
+ int i, dirty_dc_nr = 0;
+ struct bcache_device *d;
+
+ mutex_lock(&bch_register_lock);
+ for (i = 0; i < c->devices_max_used; i++) {
+ if (!c->devices[i])
+ continue;
+ if (UUID_FLASH_ONLY(&c->uuids[i]))
+ continue;
+ d = c->devices[i];
+ dc = container_of(d, struct cached_dev, disk);
+ if (atomic_read(&dc->has_dirty))
+ dirty_dc_nr++;
+ }
+ mutex_unlock(&bch_register_lock);
+
+ /*
+ * Idle_counter is increased everytime when update_writeback_rate()
+ * is rescheduled in. If all backing devices attached to the same
+ * cache set has same dc->writeback_rate_update_seconds value, it
+ * is about 10 rounds of update_writeback_rate() is called on each
+ * backing device, then the code will fall through at set 1 to
+ * c->at_max_writeback_rate, and a max wrteback rate to each
+ * dc->writeback_rate.rate. This is not very accurate but works well
+ * to make sure the whole cache set has no new I/O coming before
+ * writeback rate is set to a max number.
+ */
+ if (atomic_inc_return(&c->idle_counter) < dirty_dc_nr * 10)
+ return false;
+
+ if (atomic_read(&c->at_max_writeback_rate) != 1)
+ atomic_set(&c->at_max_writeback_rate, 1);
+
+
+ atomic64_set(&dc->writeback_rate.rate, INT_MAX);
+
+ /* keep writeback_rate_target as existing value */
+ dc->writeback_rate_proportional = 0;
+ dc->writeback_rate_integral_scaled = 0;
+ dc->writeback_rate_change = 0;
+
+ /*
+ * Check c->idle_counter and c->at_max_writeback_rate agagain in case
+ * new I/O arrives during before set_at_max_writeback_rate() returns.
+ * Then the writeback rate is set to 1, and its new value should be
+ * decided via __update_writeback_rate().
+ */
+ if (atomic_read(&c->idle_counter) < dirty_dc_nr * 10 ||
+ !atomic_read(&c->at_max_writeback_rate))
+ return false;
+
+ return true;
+}
+
static void __update_writeback_rate(struct cached_dev *dc)
{
/*
@@ -104,8 +161,9 @@ static void __update_writeback_rate(struct cached_dev *dc)
dc->writeback_rate_proportional = proportional_scaled;
dc->writeback_rate_integral_scaled = integral_scaled;
- dc->writeback_rate_change = new_rate - dc->writeback_rate.rate;
- dc->writeback_rate.rate = new_rate;
+ dc->writeback_rate_change = new_rate -
+ atomic64_read(&dc->writeback_rate.rate);
+ atomic64_set(&dc->writeback_rate.rate, new_rate);
dc->writeback_rate_target = target;
}
@@ -138,9 +196,16 @@ static void update_writeback_rate(struct work_struct *work)
down_read(&dc->writeback_lock);
- if (atomic_read(&dc->has_dirty) &&
- dc->writeback_percent)
- __update_writeback_rate(dc);
+ if (atomic_read(&dc->has_dirty) && dc->writeback_percent) {
+ /*
+ * If the whole cache set is idle, set_at_max_writeback_rate()
+ * will set writeback rate to a max number. Then it is
+ * unncessary to update writeback rate for an idle cache set
+ * in maximum writeback rate number(s).
+ */
+ if (!set_at_max_writeback_rate(c, dc))
+ __update_writeback_rate(dc);
+ }
up_read(&dc->writeback_lock);
@@ -422,27 +487,6 @@ static void read_dirty(struct cached_dev *dc)
delay = writeback_delay(dc, size);
- /* If the control system would wait for at least half a
- * second, and there's been no reqs hitting the backing disk
- * for awhile: use an alternate mode where we have at most
- * one contiguous set of writebacks in flight at a time. If
- * someone wants to do IO it will be quick, as it will only
- * have to contend with one operation in flight, and we'll
- * be round-tripping data to the backing disk as quickly as
- * it can accept it.
- */
- if (delay >= HZ / 2) {
- /* 3 means at least 1.5 seconds, up to 7.5 if we
- * have slowed way down.
- */
- if (atomic_inc_return(&dc->backing_idle) >= 3) {
- /* Wait for current I/Os to finish */
- closure_sync(&cl);
- /* And immediately launch a new set. */
- delay = 0;
- }
- }
-
while (!kthread_should_stop() &&
!test_bit(CACHE_SET_IO_DISABLE, &dc->disk.c->flags) &&
delay) {
@@ -715,7 +759,7 @@ void bch_cached_dev_writeback_init(struct cached_dev *dc)
dc->writeback_running = true;
dc->writeback_percent = 10;
dc->writeback_delay = 30;
- dc->writeback_rate.rate = 1024;
+ atomic64_set(&dc->writeback_rate.rate, 1024);
dc->writeback_rate_minimum = 8;
dc->writeback_rate_update_seconds = WRITEBACK_RATE_UPDATE_SECS_DEFAULT;
--
2.17.1