4.9-stable review patch. If anyone has any objections, please let me know.
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From: Will Deacon will.deacon@arm.com
commit 9b0de864b5bc upstream.
Since an mm has both a kernel and a user ASID, we need to ensure that broadcast TLB maintenance targets both address spaces so that things like CoW continue to work with the uaccess primitives in the kernel.
Reviewed-by: Mark Rutland mark.rutland@arm.com Tested-by: Laura Abbott labbott@redhat.com Tested-by: Shanker Donthineni shankerd@codeaurora.org Signed-off-by: Will Deacon will.deacon@arm.com Signed-off-by: Alex Shi alex.shi@linaro.org [v4.9 backport] Signed-off-by: Mark Rutland mark.rutland@arm.com [v4.9 backport] Tested-by: Will Deacon will.deacon@arm.com Tested-by: Greg Hackmann ghackmann@google.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- arch/arm64/include/asm/tlbflush.h | 16 ++++++++++++++-- 1 file changed, 14 insertions(+), 2 deletions(-)
--- a/arch/arm64/include/asm/tlbflush.h +++ b/arch/arm64/include/asm/tlbflush.h @@ -23,6 +23,7 @@
#include <linux/sched.h> #include <asm/cputype.h> +#include <asm/mmu.h>
/* * Raw TLBI operations. @@ -42,6 +43,11 @@
#define __tlbi(op, ...) __TLBI_N(op, ##__VA_ARGS__, 1, 0)
+#define __tlbi_user(op, arg) do { \ + if (arm64_kernel_unmapped_at_el0()) \ + __tlbi(op, (arg) | USER_ASID_FLAG); \ +} while (0) + /* * TLB Management * ============== @@ -103,6 +109,7 @@ static inline void flush_tlb_mm(struct m
dsb(ishst); __tlbi(aside1is, asid); + __tlbi_user(aside1is, asid); dsb(ish); }
@@ -113,6 +120,7 @@ static inline void flush_tlb_page(struct
dsb(ishst); __tlbi(vale1is, addr); + __tlbi_user(vale1is, addr); dsb(ish); }
@@ -139,10 +147,13 @@ static inline void __flush_tlb_range(str
dsb(ishst); for (addr = start; addr < end; addr += 1 << (PAGE_SHIFT - 12)) { - if (last_level) + if (last_level) { __tlbi(vale1is, addr); - else + __tlbi_user(vale1is, addr); + } else { __tlbi(vae1is, addr); + __tlbi_user(vae1is, addr); + } } dsb(ish); } @@ -182,6 +193,7 @@ static inline void __flush_tlb_pgtable(s unsigned long addr = uaddr >> 12 | (ASID(mm) << 48);
__tlbi(vae1is, addr); + __tlbi_user(vae1is, addr); dsb(ish); }