| Message ID | 20210523155338.3254465-1-npiggin@gmail.com (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | KVM: PPC: Book3S HV: Fix reverse map real-mode address lookup with huge vmalloc | expand |
| Related | show |
| Context | Check | Description |
|---|---|---|
| snowpatch_ozlabs/apply_patch | success | Successfully applied on branch powerpc/merge (8dbbcb8a8856c6b4e56ae705218d8dad1f9cf1e9) |
| snowpatch_ozlabs/build-ppc64le | success | Build succeeded |
| snowpatch_ozlabs/build-ppc64be | success | Build succeeded |
| snowpatch_ozlabs/build-ppc64e | success | Build succeeded |
| snowpatch_ozlabs/build-pmac32 | success | Build succeeded |
| snowpatch_ozlabs/checkpatch | success | total: 0 errors, 0 warnings, 0 checks, 28 lines checked |
| snowpatch_ozlabs/needsstable | success | Patch fixes a commit that hasn't been released yet |
Nicholas Piggin <npiggin@gmail.com> a écrit : > real_vmalloc_addr() does not currently work for huge vmalloc, which is > what the reverse map can be allocated with for radix host, hash guest. > > Add huge page awareness to the function. > > Fixes: 8abddd968a30 ("powerpc/64s/radix: Enable huge vmalloc mappings") > Signed-off-by: Nicholas Piggin <npiggin@gmail.com> > --- > arch/powerpc/kvm/book3s_hv_rm_mmu.c | 17 ++++++++++++----- > 1 file changed, 12 insertions(+), 5 deletions(-) > > diff --git a/arch/powerpc/kvm/book3s_hv_rm_mmu.c > b/arch/powerpc/kvm/book3s_hv_rm_mmu.c > index 7af7c70f1468..5f68cb5cc009 100644 > --- a/arch/powerpc/kvm/book3s_hv_rm_mmu.c > +++ b/arch/powerpc/kvm/book3s_hv_rm_mmu.c > @@ -26,16 +26,23 @@ > static void *real_vmalloc_addr(void *x) > { > unsigned long addr = (unsigned long) x; > + unsigned long mask; > + int shift; > pte_t *p; > + > /* > - * assume we don't have huge pages in vmalloc space... > - * So don't worry about THP collapse/split. Called > - * Only in realmode with MSR_EE = 0, hence won't need irq_save/restore. > + * This is called only in realmode with MSR_EE = 0, hence won't need > + * irq_save/restore around find_init_mm_pte. > */ > - p = find_init_mm_pte(addr, NULL); > + p = find_init_mm_pte(addr, &shift); > if (!p || !pte_present(*p)) > return NULL; > - addr = (pte_pfn(*p) << PAGE_SHIFT) | (addr & ~PAGE_MASK); > + if (!shift) > + shift = PAGE_SHIFT; > + > + mask = (1UL << shift) - 1; > + addr = (pte_pfn(*p) << PAGE_SHIFT) | (addr & mask); Looks strange, before we have ~MASK now we have mask without the ~ Also use PFN_PHYS() instead of open coding ? > + > return __va(addr); > } > > -- > 2.23.0
Christophe Leroy <christophe.leroy@csgroup.eu> writes: > Nicholas Piggin <npiggin@gmail.com> a écrit : > >> real_vmalloc_addr() does not currently work for huge vmalloc, which is >> what the reverse map can be allocated with for radix host, hash guest. >> >> Add huge page awareness to the function. >> >> Fixes: 8abddd968a30 ("powerpc/64s/radix: Enable huge vmalloc mappings") >> Signed-off-by: Nicholas Piggin <npiggin@gmail.com> >> --- >> arch/powerpc/kvm/book3s_hv_rm_mmu.c | 17 ++++++++++++----- >> 1 file changed, 12 insertions(+), 5 deletions(-) >> >> diff --git a/arch/powerpc/kvm/book3s_hv_rm_mmu.c >> b/arch/powerpc/kvm/book3s_hv_rm_mmu.c >> index 7af7c70f1468..5f68cb5cc009 100644 >> --- a/arch/powerpc/kvm/book3s_hv_rm_mmu.c >> +++ b/arch/powerpc/kvm/book3s_hv_rm_mmu.c >> @@ -26,16 +26,23 @@ >> static void *real_vmalloc_addr(void *x) >> { >> unsigned long addr = (unsigned long) x; >> + unsigned long mask; >> + int shift; >> pte_t *p; >> + >> /* >> - * assume we don't have huge pages in vmalloc space... >> - * So don't worry about THP collapse/split. Called >> - * Only in realmode with MSR_EE = 0, hence won't need irq_save/restore. >> + * This is called only in realmode with MSR_EE = 0, hence won't need >> + * irq_save/restore around find_init_mm_pte. >> */ >> - p = find_init_mm_pte(addr, NULL); >> + p = find_init_mm_pte(addr, &shift); >> if (!p || !pte_present(*p)) >> return NULL; >> - addr = (pte_pfn(*p) << PAGE_SHIFT) | (addr & ~PAGE_MASK); >> + if (!shift) >> + shift = PAGE_SHIFT; >> + >> + mask = (1UL << shift) - 1; >> + addr = (pte_pfn(*p) << PAGE_SHIFT) | (addr & mask); > > Looks strange, before we have ~MASK now we have mask without the ~ #define PAGE_MASK (~((1 << PAGE_SHIFT) - 1)) -aneesh
diff --git a/arch/powerpc/kvm/book3s_hv_rm_mmu.c b/arch/powerpc/kvm/book3s_hv_rm_mmu.c index 7af7c70f1468..5f68cb5cc009 100644 --- a/arch/powerpc/kvm/book3s_hv_rm_mmu.c +++ b/arch/powerpc/kvm/book3s_hv_rm_mmu.c @@ -26,16 +26,23 @@ static void *real_vmalloc_addr(void *x) { unsigned long addr = (unsigned long) x; + unsigned long mask; + int shift; pte_t *p; + /* - * assume we don't have huge pages in vmalloc space... - * So don't worry about THP collapse/split. Called - * Only in realmode with MSR_EE = 0, hence won't need irq_save/restore. + * This is called only in realmode with MSR_EE = 0, hence won't need + * irq_save/restore around find_init_mm_pte. */ - p = find_init_mm_pte(addr, NULL); + p = find_init_mm_pte(addr, &shift); if (!p || !pte_present(*p)) return NULL; - addr = (pte_pfn(*p) << PAGE_SHIFT) | (addr & ~PAGE_MASK); + if (!shift) + shift = PAGE_SHIFT; + + mask = (1UL << shift) - 1; + addr = (pte_pfn(*p) << PAGE_SHIFT) | (addr & mask); + return __va(addr); }
real_vmalloc_addr() does not currently work for huge vmalloc, which is what the reverse map can be allocated with for radix host, hash guest. Add huge page awareness to the function. Fixes: 8abddd968a30 ("powerpc/64s/radix: Enable huge vmalloc mappings") Signed-off-by: Nicholas Piggin <npiggin@gmail.com> --- arch/powerpc/kvm/book3s_hv_rm_mmu.c | 17 ++++++++++++----- 1 file changed, 12 insertions(+), 5 deletions(-)