From 34d49937e480edfa173d71e8c17972ad866b56c6 Mon Sep 17 00:00:00 2001 From: Peter Maydell Date: Mon, 20 Nov 2017 18:08:28 +0000 Subject: accel/tcg: Handle atomic accesses to notdirty memory correctly To do a write to memory that is marked as notdirty, we need to invalidate any TBs we have cached for that memory, and update the cpu physical memory dirty flags for VGA and migration. The slowpath code in notdirty_mem_write() does all this correctly, but the new atomic handling code in atomic_mmu_lookup() doesn't do anything at all, it just clears the dirty bit in the TLB. The effect of this bug is that if the first write to a notdirty page for which we have cached TBs is by a guest atomic access, we fail to invalidate the TBs and subsequently will execute incorrect code. This can be seen by trying to run 'javac' on AArch64. Use the new notdirty_call_before() and notdirty_call_after() functions to correctly handle the update to notdirty memory in the atomic codepath. Cc: qemu-stable@nongnu.org Signed-off-by: Peter Maydell Reviewed-by: Paolo Bonzini Reviewed-by: Richard Henderson Message-id: 1511201308-23580-3-git-send-email-peter.maydell@linaro.org --- accel/tcg/user-exec.c | 1 + 1 file changed, 1 insertion(+) (limited to 'accel/tcg/user-exec.c') diff --git a/accel/tcg/user-exec.c b/accel/tcg/user-exec.c index 0324ba8ad1..f42285ea1c 100644 --- a/accel/tcg/user-exec.c +++ b/accel/tcg/user-exec.c @@ -624,6 +624,7 @@ static void *atomic_mmu_lookup(CPUArchState *env, target_ulong addr, } /* Macro to call the above, with local variables from the use context. */ +#define ATOMIC_MMU_DECLS do {} while (0) #define ATOMIC_MMU_LOOKUP atomic_mmu_lookup(env, addr, DATA_SIZE, GETPC()) #define ATOMIC_MMU_CLEANUP do { helper_retaddr = 0; } while (0) -- cgit 1.4.1