The patch titled
KVM: MMU: Detect oom conditions and propagate error to userspace
has been added to the -mm tree. Its filename is
kvm-mmu-detect-oom-conditions-and-propagate-error-to-userspace.patch
See http://www.zip.com.au/~akpm/linux/patches/stuff/added-to-mm.txt to find
out what to do about this
------------------------------------------------------
Subject: KVM: MMU: Detect oom conditions and propagate error to userspace
From: Avi Kivity <avi@xxxxxxxxxxxx>
Signed-off-by: Avi Kivity <avi@xxxxxxxxxxxx>
Acked-by: Ingo Molnar <mingo@xxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxx>
---
drivers/kvm/mmu.c | 32 +++++++++++++++++++++-----------
drivers/kvm/paging_tmpl.h | 8 ++++++--
drivers/kvm/svm.c | 14 +++++++++++---
drivers/kvm/vmx.c | 15 ++++++++++++---
4 files changed, 50 insertions(+), 19 deletions(-)
diff -puN drivers/kvm/mmu.c~kvm-mmu-detect-oom-conditions-and-propagate-error-to-userspace drivers/kvm/mmu.c
--- a/drivers/kvm/mmu.c~kvm-mmu-detect-oom-conditions-and-propagate-error-to-userspace
+++ a/drivers/kvm/mmu.c
@@ -166,19 +166,20 @@ static int is_rmap_pte(u64 pte)
== (PT_WRITABLE_MASK | PT_PRESENT_MASK);
}
-static void mmu_topup_memory_cache(struct kvm_mmu_memory_cache *cache,
- size_t objsize, int min)
+static int mmu_topup_memory_cache(struct kvm_mmu_memory_cache *cache,
+ size_t objsize, int min)
{
void *obj;
if (cache->nobjs >= min)
- return;
+ return 0;
while (cache->nobjs < ARRAY_SIZE(cache->objects)) {
obj = kzalloc(objsize, GFP_NOWAIT);
if (!obj)
- BUG();
+ return -ENOMEM;
cache->objects[cache->nobjs++] = obj;
}
+ return 0;
}
static void mmu_free_memory_cache(struct kvm_mmu_memory_cache *mc)
@@ -187,12 +188,18 @@ static void mmu_free_memory_cache(struct
kfree(mc->objects[--mc->nobjs]);
}
-static void mmu_topup_memory_caches(struct kvm_vcpu *vcpu)
+static int mmu_topup_memory_caches(struct kvm_vcpu *vcpu)
{
- mmu_topup_memory_cache(&vcpu->mmu_pte_chain_cache,
- sizeof(struct kvm_pte_chain), 4);
- mmu_topup_memory_cache(&vcpu->mmu_rmap_desc_cache,
- sizeof(struct kvm_rmap_desc), 1);
+ int r;
+
+ r = mmu_topup_memory_cache(&vcpu->mmu_pte_chain_cache,
+ sizeof(struct kvm_pte_chain), 4);
+ if (r)
+ goto out;
+ r = mmu_topup_memory_cache(&vcpu->mmu_rmap_desc_cache,
+ sizeof(struct kvm_rmap_desc), 1);
+out:
+ return r;
}
static void mmu_free_memory_caches(struct kvm_vcpu *vcpu)
@@ -824,8 +831,11 @@ static int nonpaging_page_fault(struct k
{
gpa_t addr = gva;
hpa_t paddr;
+ int r;
- mmu_topup_memory_caches(vcpu);
+ r = mmu_topup_memory_caches(vcpu);
+ if (r)
+ return r;
ASSERT(vcpu);
ASSERT(VALID_PAGE(vcpu->mmu.root_hpa));
@@ -1052,7 +1062,7 @@ int kvm_mmu_reset_context(struct kvm_vcp
r = init_kvm_mmu(vcpu);
if (r < 0)
goto out;
- mmu_topup_memory_caches(vcpu);
+ r = mmu_topup_memory_caches(vcpu);
out:
return r;
}
diff -puN drivers/kvm/paging_tmpl.h~kvm-mmu-detect-oom-conditions-and-propagate-error-to-userspace drivers/kvm/paging_tmpl.h
--- a/drivers/kvm/paging_tmpl.h~kvm-mmu-detect-oom-conditions-and-propagate-error-to-userspace
+++ a/drivers/kvm/paging_tmpl.h
@@ -339,7 +339,8 @@ static int FNAME(fix_write_pf)(struct kv
* - normal guest page fault due to the guest pte marked not present, not
* writable, or not executable
*
- * Returns: 1 if we need to emulate the instruction, 0 otherwise
+ * Returns: 1 if we need to emulate the instruction, 0 otherwise, or
+ * a negative value on error.
*/
static int FNAME(page_fault)(struct kvm_vcpu *vcpu, gva_t addr,
u32 error_code)
@@ -351,10 +352,13 @@ static int FNAME(page_fault)(struct kvm_
u64 *shadow_pte;
int fixed;
int write_pt = 0;
+ int r;
pgprintk("%s: addr %lx err %x\n", __FUNCTION__, addr, error_code);
- mmu_topup_memory_caches(vcpu);
+ r = mmu_topup_memory_caches(vcpu);
+ if (r)
+ return r;
/*
* Look up the shadow pte for the faulting address.
diff -puN drivers/kvm/svm.c~kvm-mmu-detect-oom-conditions-and-propagate-error-to-userspace drivers/kvm/svm.c
--- a/drivers/kvm/svm.c~kvm-mmu-detect-oom-conditions-and-propagate-error-to-userspace
+++ a/drivers/kvm/svm.c
@@ -852,6 +852,7 @@ static int pf_interception(struct kvm_vc
u64 fault_address;
u32 error_code;
enum emulation_result er;
+ int r;
if (is_external_interrupt(exit_int_info))
push_irq(vcpu, exit_int_info & SVM_EVTINJ_VEC_MASK);
@@ -860,7 +861,12 @@ static int pf_interception(struct kvm_vc
fault_address = vcpu->svm->vmcb->control.exit_info_2;
error_code = vcpu->svm->vmcb->control.exit_info_1;
- if (!kvm_mmu_page_fault(vcpu, fault_address, error_code)) {
+ r = kvm_mmu_page_fault(vcpu, fault_address, error_code);
+ if (r < 0) {
+ spin_unlock(&vcpu->kvm->lock);
+ return r;
+ }
+ if (!r) {
spin_unlock(&vcpu->kvm->lock);
return 1;
}
@@ -1398,6 +1404,7 @@ static int svm_vcpu_run(struct kvm_vcpu
u16 fs_selector;
u16 gs_selector;
u16 ldt_selector;
+ int r;
again:
do_interrupt_requests(vcpu, kvm_run);
@@ -1565,7 +1572,8 @@ again:
return 0;
}
- if (handle_exit(vcpu, kvm_run)) {
+ r = handle_exit(vcpu, kvm_run);
+ if (r > 0) {
if (signal_pending(current)) {
++kvm_stat.signal_exits;
post_kvm_run_save(vcpu, kvm_run);
@@ -1581,7 +1589,7 @@ again:
goto again;
}
post_kvm_run_save(vcpu, kvm_run);
- return 0;
+ return r;
}
static void svm_flush_tlb(struct kvm_vcpu *vcpu)
diff -puN drivers/kvm/vmx.c~kvm-mmu-detect-oom-conditions-and-propagate-error-to-userspace drivers/kvm/vmx.c
--- a/drivers/kvm/vmx.c~kvm-mmu-detect-oom-conditions-and-propagate-error-to-userspace
+++ a/drivers/kvm/vmx.c
@@ -1289,6 +1289,7 @@ static int handle_exception(struct kvm_v
unsigned long cr2, rip;
u32 vect_info;
enum emulation_result er;
+ int r;
vect_info = vmcs_read32(IDT_VECTORING_INFO_FIELD);
intr_info = vmcs_read32(VM_EXIT_INTR_INFO);
@@ -1317,7 +1318,12 @@ static int handle_exception(struct kvm_v
cr2 = vmcs_readl(EXIT_QUALIFICATION);
spin_lock(&vcpu->kvm->lock);
- if (!kvm_mmu_page_fault(vcpu, cr2, error_code)) {
+ r = kvm_mmu_page_fault(vcpu, cr2, error_code);
+ if (r < 0) {
+ spin_unlock(&vcpu->kvm->lock);
+ return r;
+ }
+ if (!r) {
spin_unlock(&vcpu->kvm->lock);
return 1;
}
@@ -1680,6 +1686,7 @@ static int vmx_vcpu_run(struct kvm_vcpu
u8 fail;
u16 fs_sel, gs_sel, ldt_sel;
int fs_gs_ldt_reload_needed;
+ int r;
again:
/*
@@ -1853,6 +1860,7 @@ again:
if (fail) {
kvm_run->exit_type = KVM_EXIT_TYPE_FAIL_ENTRY;
kvm_run->exit_reason = vmcs_read32(VM_INSTRUCTION_ERROR);
+ r = 0;
} else {
if (fs_gs_ldt_reload_needed) {
load_ldt(ldt_sel);
@@ -1872,7 +1880,8 @@ again:
}
vcpu->launched = 1;
kvm_run->exit_type = KVM_EXIT_TYPE_VM_EXIT;
- if (kvm_handle_exit(kvm_run, vcpu)) {
+ r = kvm_handle_exit(kvm_run, vcpu);
+ if (r > 0) {
/* Give scheduler a change to reschedule. */
if (signal_pending(current)) {
++kvm_stat.signal_exits;
@@ -1892,7 +1901,7 @@ again:
}
post_kvm_run_save(vcpu, kvm_run);
- return 0;
+ return r;
}
static void vmx_flush_tlb(struct kvm_vcpu *vcpu)
_
Patches currently in -mm which might be from avi@xxxxxxxxxxxx are
kvm-fix-gfp_kernel-alloc-in-atomic-section-bug.patch
kvm-use-raw_smp_processor_id-instead-of-smp_processor_id-where-applicable.patch
kvm-recover-after-an-arch-module-load-failure.patch
kvm-improve-interrupt-response.patch
kvm-prevent-stale-bits-in-cr0-and-cr4.patch
kvm-mmu-implement-simple-reverse-mapping.patch
kvm-mmu-teach-the-page-table-walker-to-track-guest-page-table-gfns.patch
kvm-mmu-load-the-pae-pdptrs-on-cr3-change-like-the-processor-does.patch
kvm-mmu-fold-fetch_guest-into-init_walker.patch
kvm-mu-special-treatment-for-shadow-pae-root-pages.patch
kvm-mmu-use-the-guest-pdptrs-instead-of-mapping-cr3-in-pae-mode.patch
kvm-mmu-make-the-shadow-page-tables-also-special-case-pae.patch
kvm-mmu-make-kvm_mmu_alloc_page-return-a-kvm_mmu_page-pointer.patch
kvm-mmu-shadow-page-table-caching.patch
kvm-mmu-write-protect-guest-pages-when-a-shadow-is-created-for-them.patch
kvm-mmu-let-the-walker-extract-the-target-page-gfn-from-the-pte.patch
kvm-mmu-support-emulated-writes-into-ram.patch
kvm-mmu-zap-shadow-page-table-entries-on-writes-to-guest-page-tables.patch
kvm-mmu-if-emulating-an-instruction-fails-try-unprotecting-the-page.patch
kvm-mmu-implement-child-shadow-unlinking.patch
kvm-mmu-kvm_mmu_put_page-only-removes-one-link-to-the-page.patch
kvm-mmu-oom-handling.patch
kvm-mmu-remove-invlpg-interception.patch
kvm-mmu-remove-release_pt_page_64.patch
kvm-mmu-handle-misaligned-accesses-to-write-protected-guest-page-tables.patch
kvm-mmu-ove-is_empty_shadow_page-above-kvm_mmu_free_page.patch
kvm-mmu-ensure-freed-shadow-pages-are-clean.patch
kvm-mmu-if-an-empty-shadow-page-is-not-empty-report-more-info.patch
kvm-mmu-page-table-write-flood-protection.patch
kvm-mmu-never-free-a-shadow-page-actively-serving-as-a-root.patch
kvm-mmu-fix-cmpxchg8b-emulation.patch
kvm-mmu-treat-user-mode-faults-as-a-hint-that-a-page-is-no-longer-a-page-table.patch
kvm-mmu-free-pages-on-kvm-destruction.patch
kvm-mmu-replace-atomic-allocations-by-preallocated-objects.patch
kvm-mmu-detect-oom-conditions-and-propagate-error-to-userspace.patch
kvm-mmu-flush-guest-tlb-when-reducing-permissions-on-a-pte.patch
kvm-mmu-destroy-mmu-while-we-still-have-a-vcpu-left.patch
kvm-mmu-add-audit-code-to-check-mappings-etc-are-correct.patch
-
To unsubscribe from this list: send the line "unsubscribe mm-commits" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
