On Fri, 22 May 2026 14:44:55 +0200 "Christophe Leroy (CS GROUP)" <[email protected]> wrote:
> Le 22/05/2026 à 14:06, Christophe Leroy (CS GROUP) a écrit : > > > > > > Le 22/05/2026 à 13:12, David Laight a écrit : > >> On Fri, 22 May 2026 11:56:02 +0200 > >> "Christophe Leroy (CS GROUP)" <[email protected]> wrote: > >> > >>> Call setup_tm_sigcontexts() before opening user access to avoid > >>> having to close and open again. > >>> > >>> Signed-off-by: Christophe Leroy (CS GROUP) <[email protected]> > >>> --- > >>> 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() > > After thinking once more, I think we can do the following, is it better > for you ? Certainly more like the expected style. setup_tm_sigcontexts() will get inlined, so it doesn't matter what values are passed as the arguments. -- David > > diff --git a/arch/powerpc/kernel/signal_64.c > b/arch/powerpc/kernel/signal_64.c > index 86bb5bb4c143..c70732e8002d 100644 > --- a/arch/powerpc/kernel/signal_64.c > +++ b/arch/powerpc/kernel/signal_64.c > @@ -203,8 +203,7 @@ static long notrace __unsafe_setup_sigcontext(struct > sigcontext __user *sc, > * examine the transactional registers in the 2nd sigcontext to > determine the > * real origin of the signal. > */ > -static long setup_tm_sigcontexts(struct sigcontext __user *sc, > - struct sigcontext __user *tm_sc, > +static long setup_tm_sigcontexts(struct rt_sigframe __user *frame, > struct task_struct *tsk, > int signr, sigset_t *set, unsigned long > handler, > unsigned long msr) > @@ -217,6 +216,8 @@ static long setup_tm_sigcontexts(struct sigcontext > __user *sc, > * Userland shall check AT_HWCAP to know wether it can rely on the > * v_regs pointer or not. > */ > + struct sigcontext __user *sc = &frame->uc.uc_mcontext; > + struct sigcontext __user *tm_sc = &frame->uc_transact.uc_mcontext; > #ifdef CONFIG_ALTIVEC > elf_vrreg_t __user *v_regs = sigcontext_vmx_regs(sc); > elf_vrreg_t __user *tm_v_regs = sigcontext_vmx_regs(tm_sc); > @@ -325,6 +326,14 @@ static long setup_tm_sigcontexts(struct sigcontext > __user *sc, > > return err; > } > +#else > +static long setup_tm_sigcontexts(struct rt_sigframe __user *frame, > + struct task_struct *tsk, > + int signr, sigset_t *set, unsigned long > handler, > + unsigned long msr) > +{ > + return -EINVAL; > +} > #endif > > /* > @@ -872,6 +881,9 @@ int handle_rt_signal64(struct ksignal *ksig, > sigset_t *set, > */ > if (!MSR_TM_ACTIVE(msr)) > prepare_setup_sigcontext(tsk); > + else > + err |= setup_tm_sigcontexts(frame, tsk, ksig->sig, NULL, > + (unsigned > long)ksig->ka.sa.sa_handler, msr); > > if (!user_write_access_begin(frame, sizeof(*frame))) > goto badframe; > @@ -889,19 +901,6 @@ 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); > > > Christophe
