Le 22/05/2026 à 13:12, David Laight a écrit :

On Fri, 22 May 2026 11:56:02 +0200
"Christophe Leroy (CS GROUP)" [off-list ref] wrote:

quoted

Call setup_tm_sigcontexts() before opening user access to avoid
having to close and open again.

Signed-off-by: Christophe Leroy (CS GROUP) <chleroy@kernel.org>
---
  arch/powerpc/kernel/signal_64.c | 22 +++++++++-------------
  1 file changed, 9 insertions(+), 13 deletions(-)

diff --git a/arch/powerpc/kernel/signal_64.c b/arch/powerpc/kernel/signal_64.c
index 86bb5bb4c143..3849af21e1d8 100644
--- a/arch/powerpc/kernel/signal_64.c
+++ b/arch/powerpc/kernel/signal_64.c

@@ -873,6 +873,15 @@ int handle_rt_signal64(struct ksignal *ksig, sigset_t *set,
  	if (!MSR_TM_ACTIVE(msr))
  		prepare_setup_sigcontext(tsk);
  
+#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
+	if (MSR_TM_ACTIVE(msr))

Can't that be done without the ugly #ifdef?
I assume MSR_TM_ACTIVE() will be zero - so it will all get optimised away.

Yes but struct rt_sigframe field uc_transact only exists when 
CONFIG_PPC_TRANSACTIONAL_MEM is defined.

And that would also require a stub setup_tm_sigcontexts()

Chistophe

-- David

quoted

+		err |= setup_tm_sigcontexts(&frame->uc.uc_mcontext,
+					    &frame->uc_transact.uc_mcontext,
+					    tsk, ksig->sig, NULL,
+					    (unsigned long)ksig->ka.sa.sa_handler,
+					    msr);
+
+#endif
  	if (!user_write_access_begin(frame, sizeof(*frame)))
  		goto badframe;
  

@@ -889,19 +898,6 @@ int handle_rt_signal64(struct ksignal *ksig, sigset_t *set,
  		 * ucontext_t (for transactional state) with its uc_link ptr.
  		 */
  		unsafe_put_user(&frame->uc_transact, &frame->uc.uc_link, badframe_block);
-
-		user_write_access_end();
-
-		err |= setup_tm_sigcontexts(&frame->uc.uc_mcontext,
-					    &frame->uc_transact.uc_mcontext,
-					    tsk, ksig->sig, NULL,
-					    (unsigned long)ksig->ka.sa.sa_handler,
-					    msr);
-
-		if (!user_write_access_begin(&frame->uc.uc_sigmask,
-					     sizeof(frame->uc.uc_sigmask)))
-			goto badframe;
-
  #endif
  	} else {
  		unsafe_put_user(0, &frame->uc.uc_link, badframe_block);