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[PATCH v5 58/67] accel/tcg: Report unaligned atomics for user-only

Richard Henderson posted 67 patches 4 years, 3 months ago
Maintainers: Paolo Bonzini <pbonzini@redhat.com>, Taylor Simpson <tsimpson@quicinc.com>, "Edgar E. Iglesias" <edgar.iglesias@gmail.com>, David Hildenbrand <david@redhat.com>, Marcel Apfelbaum <marcel.apfelbaum@gmail.com>, Greg Kurz <groug@kaod.org>, Cornelia Huck <cohuck@redhat.com>, Aleksandar Rikalo <aleksandar.rikalo@syrmia.com>, Richard Henderson <richard.henderson@linaro.org>, "Philippe Mathieu-Daudé" <f4bug@amsat.org>, Thomas Huth <thuth@redhat.com>, David Gibson <david@gibson.dropbear.id.au>, Artyom Tarasenko <atar4qemu@gmail.com>, Laurent Vivier <laurent@vivier.eu>, Aurelien Jarno <aurelien@aurel32.net>, Eduardo Habkost <ehabkost@redhat.com>, Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>, Riku Voipio <riku.voipio@iki.fi>, Peter Maydell <peter.maydell@linaro.org>, Yoshinori Sato <ysato@users.sourceforge.jp>, Jiaxun Yang <jiaxun.yang@flygoat.com>, "Philippe Mathieu-Daudé" <philmd@redhat.com>
There is a newer version of this series
[PATCH v5 58/67] accel/tcg: Report unaligned atomics for user-only
Posted by Richard Henderson 4 years, 3 months ago 
Use the new cpu_loop_exit_sigbus for atomic_mmu_lookup, which
has access to complete alignment info from the TCGMemOpIdx arg.

Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
---
 accel/tcg/user-exec.c | 13 ++++++++++++-
 1 file changed, 12 insertions(+), 1 deletion(-)

diff --git a/accel/tcg/user-exec.c b/accel/tcg/user-exec.c
index 5646f8e527..92cbffd7c6 100644
--- a/accel/tcg/user-exec.c
+++ b/accel/tcg/user-exec.c
@@ -476,11 +476,22 @@ static void *atomic_mmu_lookup(CPUArchState *env, target_ulong addr,
                                MemOpIdx oi, int size, int prot,
                                uintptr_t retaddr)
 {
+    MemOp mop = get_memop(oi);
+    int a_bits = get_alignment_bits(mop);
+    void *ret;
+
+    /* Enforce guest required alignment.  */
+    if (unlikely(addr & ((1 << a_bits) - 1))) {
+        MMUAccessType t = prot == PAGE_READ ? MMU_DATA_LOAD : MMU_DATA_STORE;
+        cpu_loop_exit_sigbus(env_cpu(env), addr, t, retaddr);
+    }
+
     /* Enforce qemu required alignment.  */
     if (unlikely(addr & (size - 1))) {
         cpu_loop_exit_atomic(env_cpu(env), retaddr);
     }
-    void *ret = g2h(env_cpu(env), addr);
+
+    ret = g2h(env_cpu(env), addr);
     set_helper_retaddr(retaddr);
     return ret;
 }
-- 
2.25.1
Re: [PATCH v5 58/67] accel/tcg: Report unaligned atomics for user-only
Posted by Warner Losh 4 years, 3 months ago 
On Thu, Oct 14, 2021 at 10:14 PM Richard Henderson <
richard.henderson@linaro.org> wrote:

> Use the new cpu_loop_exit_sigbus for atomic_mmu_lookup, which
> has access to complete alignment info from the TCGMemOpIdx arg.
>
> Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
> ---
>  accel/tcg/user-exec.c | 13 ++++++++++++-
>  1 file changed, 12 insertions(+), 1 deletion(-)
>

Reviewed-by: Warner Losh <imp@bsdimp.com>



> diff --git a/accel/tcg/user-exec.c b/accel/tcg/user-exec.c
> index 5646f8e527..92cbffd7c6 100644
> --- a/accel/tcg/user-exec.c
> +++ b/accel/tcg/user-exec.c
> @@ -476,11 +476,22 @@ static void *atomic_mmu_lookup(CPUArchState *env,
> target_ulong addr,
>                                 MemOpIdx oi, int size, int prot,
>                                 uintptr_t retaddr)
>  {
> +    MemOp mop = get_memop(oi);
> +    int a_bits = get_alignment_bits(mop);
> +    void *ret;
> +
> +    /* Enforce guest required alignment.  */
> +    if (unlikely(addr & ((1 << a_bits) - 1))) {
> +        MMUAccessType t = prot == PAGE_READ ? MMU_DATA_LOAD :
> MMU_DATA_STORE;
> +        cpu_loop_exit_sigbus(env_cpu(env), addr, t, retaddr);
> +    }
> +
>      /* Enforce qemu required alignment.  */
>      if (unlikely(addr & (size - 1))) {
>          cpu_loop_exit_atomic(env_cpu(env), retaddr);
>      }
> -    void *ret = g2h(env_cpu(env), addr);
> +
> +    ret = g2h(env_cpu(env), addr);
>      set_helper_retaddr(retaddr);
>      return ret;
>  }
> --
> 2.25.1
>
>
Re: [PATCH v5 58/67] accel/tcg: Report unaligned atomics for user-only
Posted by Philippe Mathieu-Daudé 4 years, 3 months ago 
On 10/15/21 06:10, Richard Henderson wrote:
> Use the new cpu_loop_exit_sigbus for atomic_mmu_lookup, which
> has access to complete alignment info from the TCGMemOpIdx arg.
> 
> Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
> ---
>  accel/tcg/user-exec.c | 13 ++++++++++++-
>  1 file changed, 12 insertions(+), 1 deletion(-)
> 
> diff --git a/accel/tcg/user-exec.c b/accel/tcg/user-exec.c
> index 5646f8e527..92cbffd7c6 100644
> --- a/accel/tcg/user-exec.c
> +++ b/accel/tcg/user-exec.c
> @@ -476,11 +476,22 @@ static void *atomic_mmu_lookup(CPUArchState *env, target_ulong addr,
>                                 MemOpIdx oi, int size, int prot,
>                                 uintptr_t retaddr)
>  {
> +    MemOp mop = get_memop(oi);
> +    int a_bits = get_alignment_bits(mop);
> +    void *ret;
> +
> +    /* Enforce guest required alignment.  */
> +    if (unlikely(addr & ((1 << a_bits) - 1))) {

           QEMU_IS_ALIGNED(addr, 1 << a_bits) ?

> +        MMUAccessType t = prot == PAGE_READ ? MMU_DATA_LOAD : MMU_DATA_STORE;
> +        cpu_loop_exit_sigbus(env_cpu(env), addr, t, retaddr);
> +    }

Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>

Patchew 2.1-devel-b67e4c2

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