Messages in this thread | | | From | Andy Lutomirski <> | Date | Sat, 1 Sep 2018 13:43:52 -0700 | Subject | Re: [PATCH] x86/vdso: fix lsl operand order |
| |
On Sat, Sep 1, 2018 at 1:14 PM, Samuel Neves <sneves@dei.uc.pt> wrote: > In the __getcpu function, lsl was using the wrong target > and destination registers. Luckily, the compiler tends to > choose %eax for both variables, so it has been working > so far. > > Cc: x86@kernel.org > Cc: stable@vger.kernel.org > Signed-off-by: Samuel Neves <sneves@dei.uc.pt>
Acked-by: Andy Lutomirski <luto@kernel.org> Fixes: a582c540ac1b ("x86/vdso: Use RDPID in preference to LSL when available")
Whoops! I even wrote a selftest just for the offending commit, but, of course, the selftest passes :( I tested this by giving gcc some gentle encouragement to allocate different registers, and the existing code is indeed wrong and the fix indeed fixes it.
--Andy
| |