target/s390x/tcg/mem_helper: Remove bad assert() statement

[PATCH] target/s390x/tcg/mem_helper: Remove bad assert() statement

Posted by Thomas Huth 1 year, 1 month ago

The "assert(!nonfault)" statement can be triggered by running the
"mvpg" s390x kvm-unit-test with TCG. According to Richard: "... the
assert looks backward. We should only arrive there if nonfault was
true for the probe (otherwise the probe would have raised the
exception directly).  I would think we could just remove the assert."

Fixes: 4049431478 ("target/s390x: Fix s390_probe_access for user-only")
Suggested-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Thomas Huth <thuth@redhat.com>
---
 target/s390x/tcg/mem_helper.c | 1 -
 1 file changed, 1 deletion(-)

diff --git a/target/s390x/tcg/mem_helper.c b/target/s390x/tcg/mem_helper.c
index 6835c26dda..adbc79b446 100644
--- a/target/s390x/tcg/mem_helper.c
+++ b/target/s390x/tcg/mem_helper.c
@@ -149,7 +149,6 @@ static inline int s390_probe_access(CPUArchState *env, target_ulong addr,
                                    nonfault, phost, ra);
 
     if (unlikely(flags & TLB_INVALID_MASK)) {
-        assert(!nonfault);
 #ifdef CONFIG_USER_ONLY
         /* Address is in TEC in system mode; see s390_cpu_record_sigsegv. */
         env->__excp_addr = addr & TARGET_PAGE_MASK;
-- 
2.31.1

Re: [PATCH] target/s390x/tcg/mem_helper: Remove bad assert() statement

Posted by David Hildenbrand 1 year, 1 month ago

On 17.03.23 14:57, Thomas Huth wrote:
> The "assert(!nonfault)" statement can be triggered by running the
> "mvpg" s390x kvm-unit-test with TCG. According to Richard: "... the
> assert looks backward. We should only arrive there if nonfault was
> true for the probe (otherwise the probe would have raised the
> exception directly).  I would think we could just remove the assert."
> 
> Fixes: 4049431478 ("target/s390x: Fix s390_probe_access for user-only")
> Suggested-by: Richard Henderson <richard.henderson@linaro.org>
> Signed-off-by: Thomas Huth <thuth@redhat.com>
> ---

Reviewed-by: David Hildenbrand <david@redhat.com>


-- 
Thanks,

David / dhildenb

Re: [PATCH] target/s390x/tcg/mem_helper: Remove bad assert() statement

Posted by Richard Henderson 1 year, 1 month ago

On 3/17/23 06:57, Thomas Huth wrote:
> The "assert(!nonfault)" statement can be triggered by running the
> "mvpg" s390x kvm-unit-test with TCG. According to Richard: "... the
> assert looks backward. We should only arrive there if nonfault was
> true for the probe (otherwise the probe would have raised the
> exception directly).  I would think we could just remove the assert."
> 
> Fixes: 4049431478 ("target/s390x: Fix s390_probe_access for user-only")
> Suggested-by: Richard Henderson<richard.henderson@linaro.org>
> Signed-off-by: Thomas Huth<thuth@redhat.com>
> ---
>   target/s390x/tcg/mem_helper.c | 1 -
>   1 file changed, 1 deletion(-)

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>

r~