Re: [PATCH] powerpc: Clear branch trap (MSR.BE) before delivering SIGTRAP

2018-04-03 Thread Michael Ellerman
Matt Evans writes: >> On 28 Mar 2018, at 11:36, Matt Evans wrote: >>> On 28 Mar 2018, at 06:54, Michael Ellerman wrote: >>> Matt Evans writes: When using SIG_DBG_BRANCH_TRACING, MSR.BE is left enabled in the user context when single_step_exception() prepares the SIGTRAP delivery.

Re: powerpc: Clear branch trap (MSR.BE) before delivering SIGTRAP

2018-04-03 Thread Michael Ellerman
On Mon, 2018-03-26 at 16:55:21 UTC, Matt Evans wrote: > When using SIG_DBG_BRANCH_TRACING, MSR.BE is left enabled in the > user context when single_step_exception() prepares the SIGTRAP > delivery. The resulting branch-trap-within-the-SIGTRAP-handler > isn't healthy. > > Commit 2538c2d08f46141550

Re: [PATCH] powerpc: Clear branch trap (MSR.BE) before delivering SIGTRAP

2018-03-29 Thread Matt Evans
Hi Michael, > On 28 Mar 2018, at 11:36, Matt Evans wrote: > > Howdy Michael, > >> On 28 Mar 2018, at 06:54, Michael Ellerman wrote: >> >> Matt Evans writes: >> >>> When using SIG_DBG_BRANCH_TRACING, MSR.BE is left enabled in the >>> user context when single_step_exception() prepares the SIG

Re: [PATCH] powerpc: Clear branch trap (MSR.BE) before delivering SIGTRAP

2018-03-28 Thread Matt Evans
Howdy Michael, > On 28 Mar 2018, at 06:54, Michael Ellerman wrote: > > Matt Evans writes: > >> When using SIG_DBG_BRANCH_TRACING, MSR.BE is left enabled in the >> user context when single_step_exception() prepares the SIGTRAP >> delivery. The resulting branch-trap-within-the-SIGTRAP-handler >

Re: [PATCH] powerpc: Clear branch trap (MSR.BE) before delivering SIGTRAP

2018-03-27 Thread Michael Ellerman
Matt Evans writes: > When using SIG_DBG_BRANCH_TRACING, MSR.BE is left enabled in the > user context when single_step_exception() prepares the SIGTRAP > delivery. The resulting branch-trap-within-the-SIGTRAP-handler > isn't healthy. > > Commit 2538c2d08f46141550a1e68819efa8fe31c6e3dc broke this,

[PATCH] powerpc: Clear branch trap (MSR.BE) before delivering SIGTRAP

2018-03-26 Thread Matt Evans
When using SIG_DBG_BRANCH_TRACING, MSR.BE is left enabled in the user context when single_step_exception() prepares the SIGTRAP delivery. The resulting branch-trap-within-the-SIGTRAP-handler isn't healthy. Commit 2538c2d08f46141550a1e68819efa8fe31c6e3dc broke this, by replacing an MSR mask operat