* [PATCH] kvm: avoid page allocation failure in kvm_set_memory_region() @ 2015-03-20 9:51 Igor Mammedov 2015-03-20 11:59 ` Marcelo Tosatti 0 siblings, 1 reply; 3+ messages in thread From: Igor Mammedov @ 2015-03-20 9:51 UTC (permalink / raw) To: kvm; +Cc: himbeere, mimi.vx, bsd, mtosatti KVM guest can fail to startup with following trace on host: qemu-system-x86: page allocation failure: order:4, mode:0x40d0 Call Trace: dump_stack+0x47/0x67 warn_alloc_failed+0xee/0x150 __alloc_pages_direct_compact+0x14a/0x150 __alloc_pages_nodemask+0x776/0xb80 alloc_kmem_pages+0x3a/0x110 kmalloc_order+0x13/0x50 kmemdup+0x1b/0x40 __kvm_set_memory_region+0x24a/0x9f0 [kvm] kvm_set_ioapic+0x130/0x130 [kvm] kvm_set_memory_region+0x21/0x40 [kvm] kvm_vm_ioctl+0x43f/0x750 [kvm] Failure happens when attempting to allocate pages for 'struct kvm_memslots', however it doesn't have to be present in physically contiguous (kmalloc-ed) address space, change allocation to kvm_kvzalloc() so that it will be vmalloc-ed when its size is more then a page. Signed-off-by: Igor Mammedov <imammedo@redhat.com> --- TODO: - work on follow up patches to allocate space for actual amount of memory_slots instead of possible maximum. --- virt/kvm/kvm_main.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index a2214d9..7ed1f5c 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -871,10 +871,10 @@ int __kvm_set_memory_region(struct kvm *kvm, goto out_free; } - slots = kmemdup(kvm->memslots, sizeof(struct kvm_memslots), - GFP_KERNEL); + slots = kvm_kvzalloc(sizeof(struct kvm_memslots)); if (!slots) goto out_free; + memcpy(slots, kvm->memslots, sizeof(struct kvm_memslots)); if ((change == KVM_MR_DELETE) || (change == KVM_MR_MOVE)) { slot = id_to_memslot(slots, mem->slot); @@ -936,7 +936,7 @@ int __kvm_set_memory_region(struct kvm *kvm, return 0; out_slots: - kfree(slots); + kvfree(slots); out_free: kvm_free_physmem_slot(kvm, &new, &old); out: -- 1.8.3.1 ^ permalink raw reply related [flat|nested] 3+ messages in thread
* Re: [PATCH] kvm: avoid page allocation failure in kvm_set_memory_region() 2015-03-20 9:51 [PATCH] kvm: avoid page allocation failure in kvm_set_memory_region() Igor Mammedov @ 2015-03-20 11:59 ` Marcelo Tosatti 2015-03-20 12:03 ` Igor Mammedov 0 siblings, 1 reply; 3+ messages in thread From: Marcelo Tosatti @ 2015-03-20 11:59 UTC (permalink / raw) To: Igor Mammedov; +Cc: kvm, himbeere, mimi.vx, bsd On Fri, Mar 20, 2015 at 09:51:26AM +0000, Igor Mammedov wrote: > KVM guest can fail to startup with following trace on host: > > qemu-system-x86: page allocation failure: order:4, mode:0x40d0 > Call Trace: > dump_stack+0x47/0x67 > warn_alloc_failed+0xee/0x150 > __alloc_pages_direct_compact+0x14a/0x150 > __alloc_pages_nodemask+0x776/0xb80 > alloc_kmem_pages+0x3a/0x110 > kmalloc_order+0x13/0x50 > kmemdup+0x1b/0x40 > __kvm_set_memory_region+0x24a/0x9f0 [kvm] > kvm_set_ioapic+0x130/0x130 [kvm] > kvm_set_memory_region+0x21/0x40 [kvm] > kvm_vm_ioctl+0x43f/0x750 [kvm] > > Failure happens when attempting to allocate pages for > 'struct kvm_memslots', however it doesn't have to be > present in physically contiguous (kmalloc-ed) address > space, change allocation to kvm_kvzalloc() so that > it will be vmalloc-ed when its size is more then a page. > > Signed-off-by: Igor Mammedov <imammedo@redhat.com> Igor, two things: 1) kvm_create_vm should also use vmalloc r = -ENOMEM; kvm->memslots = kzalloc(sizeof(struct kvm_memslots), GFP_KERNEL); if (!kvm->memslots) goto out_err_no_srcu; 2) there are additional places where its necessary to use proper freeing function, i believe: diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index ce7888a..651ff2d 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -522,7 +522,7 @@ out_err_no_srcu: out_err_no_disable: for (i = 0; i < KVM_NR_BUSES; i++) kfree(kvm->buses[i]); - kfree(kvm->memslots); + kvfree(kvm->memslots); kvm_arch_free_vm(kvm); return ERR_PTR(r); } @@ -570,7 +570,7 @@ static void kvm_free_physmem(struct kvm *kvm) kvm_for_each_memslot(memslot, slots) kvm_free_physmem_slot(kvm, memslot, NULL); - kfree(kvm->memslots); + kvfree(kvm->memslots); } static void kvm_destroy_devices(struct kvm *kvm) @@ -909,7 +922,7 @@ int __kvm_set_memory_region(struct kvm *kvm, kvm_arch_commit_memory_region(kvm, mem, &old, change); kvm_free_physmem_slot(kvm, &old, &new); - kfree(old_memslots); + kvfree(old_memslots); /* * IOMMU mapping: New slots need to be mapped. Old slots need to be > --- > TODO: > - work on follow up patches to allocate space for > actual amount of memory_slots instead of possible maximum. > --- > virt/kvm/kvm_main.c | 6 +++--- > 1 file changed, 3 insertions(+), 3 deletions(-) > > diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c > index a2214d9..7ed1f5c 100644 > --- a/virt/kvm/kvm_main.c > +++ b/virt/kvm/kvm_main.c > @@ -871,10 +871,10 @@ int __kvm_set_memory_region(struct kvm *kvm, > goto out_free; > } > > - slots = kmemdup(kvm->memslots, sizeof(struct kvm_memslots), > - GFP_KERNEL); > + slots = kvm_kvzalloc(sizeof(struct kvm_memslots)); > if (!slots) > goto out_free; > + memcpy(slots, kvm->memslots, sizeof(struct kvm_memslots)); > > if ((change == KVM_MR_DELETE) || (change == KVM_MR_MOVE)) { > slot = id_to_memslot(slots, mem->slot); > @@ -936,7 +936,7 @@ int __kvm_set_memory_region(struct kvm *kvm, > return 0; > > out_slots: > - kfree(slots); > + kvfree(slots); > out_free: > kvm_free_physmem_slot(kvm, &new, &old); > out: > -- > 1.8.3.1 ^ permalink raw reply related [flat|nested] 3+ messages in thread
* Re: [PATCH] kvm: avoid page allocation failure in kvm_set_memory_region() 2015-03-20 11:59 ` Marcelo Tosatti @ 2015-03-20 12:03 ` Igor Mammedov 0 siblings, 0 replies; 3+ messages in thread From: Igor Mammedov @ 2015-03-20 12:03 UTC (permalink / raw) To: Marcelo Tosatti; +Cc: kvm, himbeere, mimi.vx, bsd On Fri, 20 Mar 2015 08:59:03 -0300 Marcelo Tosatti <mtosatti@redhat.com> wrote: > On Fri, Mar 20, 2015 at 09:51:26AM +0000, Igor Mammedov wrote: > > KVM guest can fail to startup with following trace on host: > > > > qemu-system-x86: page allocation failure: order:4, mode:0x40d0 > > Call Trace: > > dump_stack+0x47/0x67 > > warn_alloc_failed+0xee/0x150 > > __alloc_pages_direct_compact+0x14a/0x150 > > __alloc_pages_nodemask+0x776/0xb80 > > alloc_kmem_pages+0x3a/0x110 > > kmalloc_order+0x13/0x50 > > kmemdup+0x1b/0x40 > > __kvm_set_memory_region+0x24a/0x9f0 [kvm] > > kvm_set_ioapic+0x130/0x130 [kvm] > > kvm_set_memory_region+0x21/0x40 [kvm] > > kvm_vm_ioctl+0x43f/0x750 [kvm] > > > > Failure happens when attempting to allocate pages for > > 'struct kvm_memslots', however it doesn't have to be > > present in physically contiguous (kmalloc-ed) address > > space, change allocation to kvm_kvzalloc() so that > > it will be vmalloc-ed when its size is more then a page. > > > > Signed-off-by: Igor Mammedov <imammedo@redhat.com> > > Igor, two things: > > 1) kvm_create_vm should also use vmalloc > > r = -ENOMEM; > kvm->memslots = kzalloc(sizeof(struct kvm_memslots), GFP_KERNEL); > if (!kvm->memslots) > goto out_err_no_srcu; > > 2) there are additional places where its necessary to use > proper freeing function, i believe: > > diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c > index ce7888a..651ff2d 100644 > --- a/virt/kvm/kvm_main.c > +++ b/virt/kvm/kvm_main.c > @@ -522,7 +522,7 @@ out_err_no_srcu: > out_err_no_disable: > for (i = 0; i < KVM_NR_BUSES; i++) > kfree(kvm->buses[i]); > - kfree(kvm->memslots); > + kvfree(kvm->memslots); > kvm_arch_free_vm(kvm); > return ERR_PTR(r); > } > @@ -570,7 +570,7 @@ static void kvm_free_physmem(struct kvm *kvm) > kvm_for_each_memslot(memslot, slots) > kvm_free_physmem_slot(kvm, memslot, NULL); > > - kfree(kvm->memslots); > + kvfree(kvm->memslots); > } > > static void kvm_destroy_devices(struct kvm *kvm) > @@ -909,7 +922,7 @@ int __kvm_set_memory_region(struct kvm *kvm, > kvm_arch_commit_memory_region(kvm, mem, &old, change); > > kvm_free_physmem_slot(kvm, &old, &new); > - kfree(old_memslots); > + kvfree(old_memslots); > > /* > * IOMMU mapping: New slots need to be mapped. Old slots need to be Thanks for review, I'll respin patch after fixing it up. > > > --- > > TODO: > > - work on follow up patches to allocate space for > > actual amount of memory_slots instead of possible maximum. > > --- > > virt/kvm/kvm_main.c | 6 +++--- > > 1 file changed, 3 insertions(+), 3 deletions(-) > > > > diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c > > index a2214d9..7ed1f5c 100644 > > --- a/virt/kvm/kvm_main.c > > +++ b/virt/kvm/kvm_main.c > > @@ -871,10 +871,10 @@ int __kvm_set_memory_region(struct kvm *kvm, > > goto out_free; > > } > > > > - slots = kmemdup(kvm->memslots, sizeof(struct kvm_memslots), > > - GFP_KERNEL); > > + slots = kvm_kvzalloc(sizeof(struct kvm_memslots)); > > if (!slots) > > goto out_free; > > + memcpy(slots, kvm->memslots, sizeof(struct kvm_memslots)); > > > > if ((change == KVM_MR_DELETE) || (change == KVM_MR_MOVE)) { > > slot = id_to_memslot(slots, mem->slot); > > @@ -936,7 +936,7 @@ int __kvm_set_memory_region(struct kvm *kvm, > > return 0; > > > > out_slots: > > - kfree(slots); > > + kvfree(slots); > > out_free: > > kvm_free_physmem_slot(kvm, &new, &old); > > out: > > -- > > 1.8.3.1 ^ permalink raw reply [flat|nested] 3+ messages in thread
end of thread, other threads:[~2015-03-20 12:03 UTC | newest] Thread overview: 3+ messages (download: mbox.gz follow: Atom feed -- links below jump to the message on this page -- 2015-03-20 9:51 [PATCH] kvm: avoid page allocation failure in kvm_set_memory_region() Igor Mammedov 2015-03-20 11:59 ` Marcelo Tosatti 2015-03-20 12:03 ` Igor Mammedov
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