| Message ID | 20230510230213.330134-2-iii@linux.ibm.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | linux-user/s390x: Fix single-stepping SVC | expand |
11.05.2023 02:02, Ilya Leoshkevich wrote: > Currently single-stepping SVC executes two instructions. The reason is > that EXCP_DEBUG for the SVC instruction itself is masked by EXCP_SVC. > Fix by re-raising EXCP_DEBUG. Is it a -stable material? /mjt
On Thu, 2023-05-11 at 13:55 +0300, Michael Tokarev wrote: > 11.05.2023 02:02, Ilya Leoshkevich wrote: > > Currently single-stepping SVC executes two instructions. The reason > > is > > that EXCP_DEBUG for the SVC instruction itself is masked by > > EXCP_SVC. > > Fix by re-raising EXCP_DEBUG. > > Is it a -stable material? > > /mjt While I would personally love to see this in -stable, I don't think it fits the official criteria - it's not a security fix and it's not a regression.
11.05.2023 14:20, Ilya Leoshkevich wrote: > On Thu, 2023-05-11 at 13:55 +0300, Michael Tokarev wrote: >> Is it a -stable material? > While I would personally love to see this in -stable, I don't think it > fits the official criteria - it's not a security fix and it's not a > regression. I'm not sure I follow. It's definitely okay to include a bug fix into -stable, this has been done countless times in the past.. /mjt
On Thu, 2023-05-11 at 15:32 +0300, Michael Tokarev wrote: > 11.05.2023 14:20, Ilya Leoshkevich wrote: > > On Thu, 2023-05-11 at 13:55 +0300, Michael Tokarev wrote: > > > > Is it a -stable material? > > > While I would personally love to see this in -stable, I don't think > > it > > fits the official criteria - it's not a security fix and it's not a > > regression. > > I'm not sure I follow. It's definitely okay to include a bug fix into > -stable, this has been done countless times in the past.. > > /mjt Okay, then let's include it into -stable. It's just that I'm not too familiar with the QEMU -stable process, so I read [1], and it sounded quite strict. [1] https://www.qemu.org/docs/master/devel/stable-process.html
11.05.2023 16:45, Ilya Leoshkevich wrote: >> 11.05.2023 14:20, Ilya Leoshkevich wrote: >>> While I would personally love to see this in -stable, I don't think it >>> fits the official criteria - it's not a security fix and it's not a >>> regression. > Okay, then let's include it into -stable. > > It's just that I'm not too familiar with the QEMU -stable process, so > I read [1], and it sounded quite strict. > > [1] https://www.qemu.org/docs/master/devel/stable-process.html The text there reads: If you think the patch would be important for users of the current release (or for a distribution picking fixes), it is usually a good candidate for stable. :) Please Cc: qemu-stable@nongnu.org the next time you think something is good to have there. /mjt
diff --git a/linux-user/s390x/cpu_loop.c b/linux-user/s390x/cpu_loop.c index 285bc60071a..8b7ac2879ef 100644 --- a/linux-user/s390x/cpu_loop.c +++ b/linux-user/s390x/cpu_loop.c @@ -86,6 +86,15 @@ void cpu_loop(CPUS390XState *env) } else if (ret != -QEMU_ESIGRETURN) { env->regs[2] = ret; } + + if (unlikely(cs->singlestep_enabled)) { + /* + * cpu_tb_exec() did not raise EXCP_DEBUG, because it has seen + * that EXCP_SVC was already pending. + */ + cs->exception_index = EXCP_DEBUG; + } + break; case EXCP_DEBUG:
Currently single-stepping SVC executes two instructions. The reason is that EXCP_DEBUG for the SVC instruction itself is masked by EXCP_SVC. Fix by re-raising EXCP_DEBUG. Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com> --- linux-user/s390x/cpu_loop.c | 9 +++++++++ 1 file changed, 9 insertions(+)