| Message ID | 1368825912-23562-3-git-send-email-sanjayl@kymasys.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Fri, May 17, 2013 at 02:25:11PM -0700, Sanjay Lal wrote: > - As suggested by Gleb, wrap calls to gfn_to_pfn() with srcu_read_lock/unlock(). > Memory slots should be acccessed from a SRCU read section. > - kvm_mips_map_page() now returns an error code to it's callers, instead of calling panic() > if it cannot find a mapping for a particular gfn. > > Signed-off-by: Sanjay Lal <sanjayl@kymasys.com> > --- > arch/mips/kvm/kvm_tlb.c | 36 +++++++++++++++++++++++++++--------- > 1 file changed, 27 insertions(+), 9 deletions(-) > > diff --git a/arch/mips/kvm/kvm_tlb.c b/arch/mips/kvm/kvm_tlb.c > index 89511a9..ab2e9b0 100644 > --- a/arch/mips/kvm/kvm_tlb.c > +++ b/arch/mips/kvm/kvm_tlb.c > @@ -16,7 +16,10 @@ > #include <linux/mm.h> > #include <linux/delay.h> > #include <linux/module.h> > +#include <linux/bootmem.h> Is this include still needed now when you export min_low_pfn in mips_ksyms.c? > #include <linux/kvm_host.h> > +#include <linux/srcu.h> > + > > #include <asm/cpu.h> > #include <asm/bootinfo.h> > @@ -169,21 +172,27 @@ void kvm_mips_dump_shadow_tlbs(struct kvm_vcpu *vcpu) > } > } > > -static void kvm_mips_map_page(struct kvm *kvm, gfn_t gfn) > +static int kvm_mips_map_page(struct kvm *kvm, gfn_t gfn) > { > + int srcu_idx, err = 0; > pfn_t pfn; > > if (kvm->arch.guest_pmap[gfn] != KVM_INVALID_PAGE) > - return; > + return 0; > > + srcu_idx = srcu_read_lock(&kvm->srcu); > pfn = kvm_mips_gfn_to_pfn(kvm, gfn); > > if (kvm_mips_is_error_pfn(pfn)) { > - panic("Couldn't get pfn for gfn %#" PRIx64 "!\n", gfn); > + kvm_err("Couldn't get pfn for gfn %#" PRIx64 "!\n", gfn); > + err = -EFAULT; > + goto out; > } > > kvm->arch.guest_pmap[gfn] = pfn; > - return; > +out: > + srcu_read_unlock(&kvm->srcu, srcu_idx); > + return err; > } > > /* Translate guest KSEG0 addresses to Host PA */ > @@ -207,7 +216,10 @@ unsigned long kvm_mips_translate_guest_kseg0_to_hpa(struct kvm_vcpu *vcpu, > gva); > return KVM_INVALID_PAGE; > } > - kvm_mips_map_page(vcpu->kvm, gfn); > + > + if (kvm_mips_map_page(vcpu->kvm, gfn) < 0) > + return KVM_INVALID_ADDR; > + > return (kvm->arch.guest_pmap[gfn] << PAGE_SHIFT) + offset; > } > > @@ -310,8 +322,11 @@ int kvm_mips_handle_kseg0_tlb_fault(unsigned long badvaddr, > even = !(gfn & 0x1); > vaddr = badvaddr & (PAGE_MASK << 1); > > - kvm_mips_map_page(vcpu->kvm, gfn); > - kvm_mips_map_page(vcpu->kvm, gfn ^ 0x1); > + if (kvm_mips_map_page(vcpu->kvm, gfn) < 0) > + return -1; > + > + if (kvm_mips_map_page(vcpu->kvm, gfn ^ 0x1) < 0) > + return -1; > > if (even) { > pfn0 = kvm->arch.guest_pmap[gfn]; > @@ -389,8 +404,11 @@ kvm_mips_handle_mapped_seg_tlb_fault(struct kvm_vcpu *vcpu, > pfn0 = 0; > pfn1 = 0; > } else { > - kvm_mips_map_page(kvm, mips3_tlbpfn_to_paddr(tlb->tlb_lo0) >> PAGE_SHIFT); > - kvm_mips_map_page(kvm, mips3_tlbpfn_to_paddr(tlb->tlb_lo1) >> PAGE_SHIFT); > + if (kvm_mips_map_page(kvm, mips3_tlbpfn_to_paddr(tlb->tlb_lo0) >> PAGE_SHIFT) < 0) > + return -1; > + > + if (kvm_mips_map_page(kvm, mips3_tlbpfn_to_paddr(tlb->tlb_lo1) >> PAGE_SHIFT) < 0) > + return -1; > > pfn0 = kvm->arch.guest_pmap[mips3_tlbpfn_to_paddr(tlb->tlb_lo0) >> PAGE_SHIFT]; > pfn1 = kvm->arch.guest_pmap[mips3_tlbpfn_to_paddr(tlb->tlb_lo1) >> PAGE_SHIFT]; > -- > 1.7.11.3 -- Gleb. -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/arch/mips/kvm/kvm_tlb.c b/arch/mips/kvm/kvm_tlb.c index 89511a9..ab2e9b0 100644 --- a/arch/mips/kvm/kvm_tlb.c +++ b/arch/mips/kvm/kvm_tlb.c @@ -16,7 +16,10 @@ #include <linux/mm.h> #include <linux/delay.h> #include <linux/module.h> +#include <linux/bootmem.h> #include <linux/kvm_host.h> +#include <linux/srcu.h> + #include <asm/cpu.h> #include <asm/bootinfo.h> @@ -169,21 +172,27 @@ void kvm_mips_dump_shadow_tlbs(struct kvm_vcpu *vcpu) } } -static void kvm_mips_map_page(struct kvm *kvm, gfn_t gfn) +static int kvm_mips_map_page(struct kvm *kvm, gfn_t gfn) { + int srcu_idx, err = 0; pfn_t pfn; if (kvm->arch.guest_pmap[gfn] != KVM_INVALID_PAGE) - return; + return 0; + srcu_idx = srcu_read_lock(&kvm->srcu); pfn = kvm_mips_gfn_to_pfn(kvm, gfn); if (kvm_mips_is_error_pfn(pfn)) { - panic("Couldn't get pfn for gfn %#" PRIx64 "!\n", gfn); + kvm_err("Couldn't get pfn for gfn %#" PRIx64 "!\n", gfn); + err = -EFAULT; + goto out; } kvm->arch.guest_pmap[gfn] = pfn; - return; +out: + srcu_read_unlock(&kvm->srcu, srcu_idx); + return err; } /* Translate guest KSEG0 addresses to Host PA */ @@ -207,7 +216,10 @@ unsigned long kvm_mips_translate_guest_kseg0_to_hpa(struct kvm_vcpu *vcpu, gva); return KVM_INVALID_PAGE; } - kvm_mips_map_page(vcpu->kvm, gfn); + + if (kvm_mips_map_page(vcpu->kvm, gfn) < 0) + return KVM_INVALID_ADDR; + return (kvm->arch.guest_pmap[gfn] << PAGE_SHIFT) + offset; } @@ -310,8 +322,11 @@ int kvm_mips_handle_kseg0_tlb_fault(unsigned long badvaddr, even = !(gfn & 0x1); vaddr = badvaddr & (PAGE_MASK << 1); - kvm_mips_map_page(vcpu->kvm, gfn); - kvm_mips_map_page(vcpu->kvm, gfn ^ 0x1); + if (kvm_mips_map_page(vcpu->kvm, gfn) < 0) + return -1; + + if (kvm_mips_map_page(vcpu->kvm, gfn ^ 0x1) < 0) + return -1; if (even) { pfn0 = kvm->arch.guest_pmap[gfn]; @@ -389,8 +404,11 @@ kvm_mips_handle_mapped_seg_tlb_fault(struct kvm_vcpu *vcpu, pfn0 = 0; pfn1 = 0; } else { - kvm_mips_map_page(kvm, mips3_tlbpfn_to_paddr(tlb->tlb_lo0) >> PAGE_SHIFT); - kvm_mips_map_page(kvm, mips3_tlbpfn_to_paddr(tlb->tlb_lo1) >> PAGE_SHIFT); + if (kvm_mips_map_page(kvm, mips3_tlbpfn_to_paddr(tlb->tlb_lo0) >> PAGE_SHIFT) < 0) + return -1; + + if (kvm_mips_map_page(kvm, mips3_tlbpfn_to_paddr(tlb->tlb_lo1) >> PAGE_SHIFT) < 0) + return -1; pfn0 = kvm->arch.guest_pmap[mips3_tlbpfn_to_paddr(tlb->tlb_lo0) >> PAGE_SHIFT]; pfn1 = kvm->arch.guest_pmap[mips3_tlbpfn_to_paddr(tlb->tlb_lo1) >> PAGE_SHIFT];
- As suggested by Gleb, wrap calls to gfn_to_pfn() with srcu_read_lock/unlock(). Memory slots should be acccessed from a SRCU read section. - kvm_mips_map_page() now returns an error code to it's callers, instead of calling panic() if it cannot find a mapping for a particular gfn. Signed-off-by: Sanjay Lal <sanjayl@kymasys.com> --- arch/mips/kvm/kvm_tlb.c | 36 +++++++++++++++++++++++++++--------- 1 file changed, 27 insertions(+), 9 deletions(-)