Re: [Qemu-devel] [PATCH] exec: Add missing rcu_read_unlock

[Paolo Bonzini]

On 09/01/2017 12:09, Roman Kapl wrote:
> rcu_read_unlock was not called if the address_space_access_valid result is
> negative.
> 
> This caused (at least) a problem when qemu on PPC/E500+TAP failed to terminate
> properly and instead got stuck in a deadlock.
> 
> Signed-off-by: Roman Kapl <address@hidden>
> ---
>  exec.c | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/exec.c b/exec.c
> index 8d4bb0e..6895db5 100644
> --- a/exec.c
> +++ b/exec.c
> @@ -2927,6 +2927,7 @@ bool address_space_access_valid(AddressSpace *as, 
> hwaddr addr, int len, bool is_
>          if (!memory_access_is_direct(mr, is_write)) {
>              l = memory_access_size(mr, l, addr);
>              if (!memory_region_access_valid(mr, xlat, l, is_write)) {
> +                rcu_read_unlock();
>                  return false;
>              }
>          }
> 

Thanks, queued!

Cc: qemu-stable <address@hidden>

Paolo