3.14-stable review patch. If anyone has any objections, please let me know.
------------------ From: Marc Zyngier <[email protected]> commit 04b8dc85bf4a64517e3cf20e409eeaa503b15cc1 upstream. [Since we don't backport commit c647355 (KVM: arm: Add initial dirty page locking support) for linux-3.14.y, there is no stage2_wp_range in arch/arm/kvm/mmu.c. So ignore the change in stage2_wp_range introduced by this patch.] The kernel's pgd_index macro is designed to index a normal, page sized array. KVM is a bit diffferent, as we can use concatenated pages to have a bigger address space (for example 40bit IPA with 4kB pages gives us an 8kB PGD. In the above case, the use of pgd_index will always return an index inside the first 4kB, which makes a guest that has memory above 0x8000000000 rather unhappy, as it spins forever in a page fault, whist the host happilly corrupts the lower pgd. The obvious fix is to get our own kvm_pgd_index that does the right thing(tm). Tested on X-Gene with a hacked kvmtool that put memory at a stupidly high address. Reviewed-by: Christoffer Dall <[email protected]> Signed-off-by: Marc Zyngier <[email protected]> Signed-off-by: Christoffer Dall <[email protected]> Signed-off-by: Shannon Zhao <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> --- arch/arm/include/asm/kvm_mmu.h | 3 ++- arch/arm/kvm/mmu.c | 6 +++--- arch/arm64/include/asm/kvm_mmu.h | 2 ++ 3 files changed, 7 insertions(+), 4 deletions(-) --- a/arch/arm/include/asm/kvm_mmu.h +++ b/arch/arm/include/asm/kvm_mmu.h @@ -117,13 +117,14 @@ static inline void kvm_set_s2pmd_writabl (__boundary - 1 < (end) - 1)? __boundary: (end); \ }) +#define kvm_pgd_index(addr) pgd_index(addr) + static inline bool kvm_page_empty(void *ptr) { struct page *ptr_page = virt_to_page(ptr); return page_count(ptr_page) == 1; } - #define kvm_pte_table_empty(ptep) kvm_page_empty(ptep) #define kvm_pmd_table_empty(pmdp) kvm_page_empty(pmdp) #define kvm_pud_table_empty(pudp) (0) --- a/arch/arm/kvm/mmu.c +++ b/arch/arm/kvm/mmu.c @@ -194,7 +194,7 @@ static void unmap_range(struct kvm *kvm, phys_addr_t addr = start, end = start + size; phys_addr_t next; - pgd = pgdp + pgd_index(addr); + pgd = pgdp + kvm_pgd_index(addr); do { next = kvm_pgd_addr_end(addr, end); if (!pgd_none(*pgd)) @@ -264,7 +264,7 @@ static void stage2_flush_memslot(struct phys_addr_t next; pgd_t *pgd; - pgd = kvm->arch.pgd + pgd_index(addr); + pgd = kvm->arch.pgd + kvm_pgd_index(addr); do { next = kvm_pgd_addr_end(addr, end); stage2_flush_puds(kvm, pgd, addr, next); @@ -649,7 +649,7 @@ static pmd_t *stage2_get_pmd(struct kvm pud_t *pud; pmd_t *pmd; - pgd = kvm->arch.pgd + pgd_index(addr); + pgd = kvm->arch.pgd + kvm_pgd_index(addr); pud = pud_offset(pgd, addr); if (pud_none(*pud)) { if (!cache) --- a/arch/arm64/include/asm/kvm_mmu.h +++ b/arch/arm64/include/asm/kvm_mmu.h @@ -69,6 +69,8 @@ #define PTRS_PER_S2_PGD (1 << (KVM_PHYS_SHIFT - PGDIR_SHIFT)) #define S2_PGD_ORDER get_order(PTRS_PER_S2_PGD * sizeof(pgd_t)) +#define kvm_pgd_index(addr) (((addr) >> PGDIR_SHIFT) & (PTRS_PER_S2_PGD - 1)) + int create_hyp_mappings(void *from, void *to); int create_hyp_io_mappings(void *from, void *to, phys_addr_t); void free_boot_hyp_pgd(void); -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
