Commit d31626f70b61 ("powerpc: Don't corrupt transactional state when
using FP/VMX in kernel") introduced a bug where the uc_link and uc_regs
fields of the ucontext_t that is created to hold the transactional
values of the registers in a 32-bit signal frame didn't get set
correctly. The reason is that we now clear the MSR_TS bits in the MSR
in save_tm_user_regs(), before the code that sets uc_link and uc_regs.
To fix this, we move the setting of uc_link and uc_regs into the same
if statement that selects whether to call save_tm_user_regs() or
save_user_regs().
Signed-off-by: Paul Mackerras <pau...@samba.org>
---
arch/powerpc/kernel/signal_32.c | 19 +++++++------------
1 file changed, 7 insertions(+), 12 deletions(-)
diff --git a/arch/powerpc/kernel/signal_32.c b/arch/powerpc/kernel/signal_32.c
index 6ce69e6..a67e00a 100644
--- a/arch/powerpc/kernel/signal_32.c
+++ b/arch/powerpc/kernel/signal_32.c
@@ -1022,29 +1022,24 @@ int handle_rt_signal32(unsigned long sig, struct
k_sigaction *ka,
#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
tm_frame = &rt_sf->uc_transact.uc_mcontext;
if (MSR_TM_ACTIVE(regs->msr)) {
+ if (__put_user((unsigned long)&rt_sf->uc_transact,
+ &rt_sf->uc.uc_link) ||
+ __put_user((unsigned long)tm_frame,
+ &rt_sf->uc_transact.uc_regs))
+ goto badframe;
if (save_tm_user_regs(regs, frame, tm_frame, sigret))
goto badframe;
}
else
#endif
{
+ if (__put_user(0, &rt_sf->uc.uc_link))
+ goto badframe;
if (save_user_regs(regs, frame, tm_frame, sigret, 1))
goto badframe;
}
regs->link = tramp;
-#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
- if (MSR_TM_ACTIVE(regs->msr)) {
- if (__put_user((unsigned long)&rt_sf->uc_transact,
- &rt_sf->uc.uc_link)
- || __put_user((unsigned long)tm_frame,
&rt_sf->uc_transact.uc_regs))
- goto badframe;
- }
- else
-#endif
- if (__put_user(0, &rt_sf->uc.uc_link))
- goto badframe;
-
current->thread.fp_state.fpscr = 0; /* turn off all fp exceptions */
/* create a stack frame for the caller of the handler */
--
1.8.5.2
_______________________________________________
Linuxppc-dev mailing list
Linuxppc-dev@lists.ozlabs.org
https://lists.ozlabs.org/listinfo/linuxppc-dev
