From cd63f3cf1d59b7ad8419eba1cac8f9126e79cc43 Mon Sep 17 00:00:00 2001 From: Gustavo Romero Date: Wed, 19 Jul 2017 01:44:13 -0400 Subject: [PATCH] powerpc/tm: Fix saving of TM SPRs in core dump Currently flush_tmregs_to_thread() does not save the TM SPRs (TFHAR, TFIAR, TEXASR) to the thread struct, unless the process is currently inside a suspended transaction. If the process is core dumping, and the TM SPRs have changed since the last time the process was context switched, then we will save stale values of the TM SPRs to the core dump. Fix it by saving the live register state to the thread struct in that case. Fixes: 08e1c01d6aed ("powerpc/ptrace: Enable support for TM SPR state") Cc: stable@vger.kernel.org # v4.8+ Signed-off-by: Gustavo Romero Reviewed-by: Cyril Bur Signed-off-by: Michael Ellerman --- arch/powerpc/kernel/ptrace.c | 13 ++++++++++--- 1 file changed, 10 insertions(+), 3 deletions(-) diff --git a/arch/powerpc/kernel/ptrace.c b/arch/powerpc/kernel/ptrace.c index 925a4ef90559..660ed39e9c9a 100644 --- a/arch/powerpc/kernel/ptrace.c +++ b/arch/powerpc/kernel/ptrace.c @@ -127,12 +127,19 @@ static void flush_tmregs_to_thread(struct task_struct *tsk) * If task is not current, it will have been flushed already to * it's thread_struct during __switch_to(). * - * A reclaim flushes ALL the state. + * A reclaim flushes ALL the state or if not in TM save TM SPRs + * in the appropriate thread structures from live. */ - if (tsk == current && MSR_TM_SUSPENDED(mfmsr())) - tm_reclaim_current(TM_CAUSE_SIGNAL); + if (tsk != current) + return; + if (MSR_TM_SUSPENDED(mfmsr())) { + tm_reclaim_current(TM_CAUSE_SIGNAL); + } else { + tm_enable(); + tm_save_sprs(&(tsk->thread)); + } } #else static inline void flush_tmregs_to_thread(struct task_struct *tsk) { }