| Message ID | 7d391d915d2bd1c0f601f55f61f8dd4c70066229.1629732940.git.christophe.leroy@csgroup.eu (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | [v2,1/5] powerpc/signal64: Access function descriptor with user access block | expand |
| Related | show |
| Context | Check | Description |
|---|---|---|
| snowpatch_ozlabs/github-powerpc_selftests | success | Successfully ran 8 jobs. |
| snowpatch_ozlabs/github-powerpc_ppctests | success | Successfully ran 8 jobs. |
| snowpatch_ozlabs/github-powerpc_clang | success | Successfully ran 8 jobs. |
| snowpatch_ozlabs/github-powerpc_sparse | success | Successfully ran 4 jobs. |
| snowpatch_ozlabs/github-powerpc_kernel_qemu | success | Successfully ran 25 jobs. |
Christophe Leroy <christophe.leroy@csgroup.eu> writes: > Use unsafe_copy_siginfo_to_user() in order to do the copy > within the user access block. > > On an mpc 8321 (book3s/32) the improvment is about 5% on a process > sending a signal to itself. Nacked-by: "Eric W. Biederman" <ebiederm@xmission.com> copy_siginfo_to_user is not the same as copy_siginfo_to_user32. As in this patch breaks 32bit userspace on powerpc. > Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> > --- > arch/powerpc/kernel/signal_32.c | 13 ++++++------- > arch/powerpc/kernel/signal_64.c | 5 +---- > 2 files changed, 7 insertions(+), 11 deletions(-) > > diff --git a/arch/powerpc/kernel/signal_32.c b/arch/powerpc/kernel/signal_32.c > index ff101e2b3bab..f9e16d108bc8 100644 > --- a/arch/powerpc/kernel/signal_32.c > +++ b/arch/powerpc/kernel/signal_32.c > @@ -710,12 +710,6 @@ static long restore_tm_user_regs(struct pt_regs *regs, struct mcontext __user *s > } > #endif > > -#ifdef CONFIG_PPC64 > - > -#define copy_siginfo_to_user copy_siginfo_to_user32 > - > -#endif /* CONFIG_PPC64 */ > - > /* > * Set up a signal frame for a "real-time" signal handler > * (one which gets siginfo). > @@ -779,14 +773,19 @@ int handle_rt_signal32(struct ksignal *ksig, sigset_t *oldset, > asm("dcbst %y0; sync; icbi %y0; sync" :: "Z" (mctx->mc_pad[0])); > } > unsafe_put_sigset_t(&frame->uc.uc_sigmask, oldset, failed); > +#ifndef CONFIG_COMPAT > + unsafe_copy_siginfo_to_user(&frame->info, &ksig->info, failed); > +#endif > > /* create a stack frame for the caller of the handler */ > unsafe_put_user(regs->gpr[1], newsp, failed); > > user_access_end(); > > - if (copy_siginfo_to_user(&frame->info, &ksig->info)) > +#ifdef CONFIG_COMPAT > + if (copy_siginfo_to_user32(&frame->info, &ksig->info)) > goto badframe; > +#endif > > regs->link = tramp; > > diff --git a/arch/powerpc/kernel/signal_64.c b/arch/powerpc/kernel/signal_64.c > index 2cca6c8febe1..82b73fbd937d 100644 > --- a/arch/powerpc/kernel/signal_64.c > +++ b/arch/powerpc/kernel/signal_64.c > @@ -901,15 +901,12 @@ int handle_rt_signal64(struct ksignal *ksig, sigset_t *set, > } > > unsafe_copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set), badframe_block); > + unsafe_copy_siginfo_to_user(&frame->info, &ksig->info, badframe_block); > /* Allocate a dummy caller frame for the signal handler. */ > unsafe_put_user(regs->gpr[1], newsp, badframe_block); > > user_write_access_end(); > > - /* Save the siginfo outside of the unsafe block. */ > - if (copy_siginfo_to_user(&frame->info, &ksig->info)) > - goto badframe; > - > /* Make sure signal handler doesn't get spurious FP exceptions */ > tsk->thread.fp_state.fpscr = 0;
Le 02/09/2021 à 20:38, Eric W. Biederman a écrit : > Christophe Leroy <christophe.leroy@csgroup.eu> writes: > >> Use unsafe_copy_siginfo_to_user() in order to do the copy >> within the user access block. >> >> On an mpc 8321 (book3s/32) the improvment is about 5% on a process >> sending a signal to itself. > > Nacked-by: "Eric W. Biederman" <ebiederm@xmission.com> > > copy_siginfo_to_user is not the same as copy_siginfo_to_user32. > > As in this patch breaks 32bit userspace on powerpc. I don't understand your comment. As you can see below, copy_siginfo_to_user32() is used in the compat case (ie 32 bit userspace on PPC64) and unsafe_copy_siginfo_to_user() is used on the non-compat case (ie 32 bit userspace on PPC32). So what's the issue really ? > > >> Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> >> --- >> arch/powerpc/kernel/signal_32.c | 13 ++++++------- >> arch/powerpc/kernel/signal_64.c | 5 +---- >> 2 files changed, 7 insertions(+), 11 deletions(-) >> >> diff --git a/arch/powerpc/kernel/signal_32.c b/arch/powerpc/kernel/signal_32.c >> index ff101e2b3bab..f9e16d108bc8 100644 >> --- a/arch/powerpc/kernel/signal_32.c >> +++ b/arch/powerpc/kernel/signal_32.c >> @@ -710,12 +710,6 @@ static long restore_tm_user_regs(struct pt_regs *regs, struct mcontext __user *s >> } >> #endif >> >> -#ifdef CONFIG_PPC64 >> - >> -#define copy_siginfo_to_user copy_siginfo_to_user32 >> - >> -#endif /* CONFIG_PPC64 */ >> - >> /* >> * Set up a signal frame for a "real-time" signal handler >> * (one which gets siginfo). >> @@ -779,14 +773,19 @@ int handle_rt_signal32(struct ksignal *ksig, sigset_t *oldset, >> asm("dcbst %y0; sync; icbi %y0; sync" :: "Z" (mctx->mc_pad[0])); >> } >> unsafe_put_sigset_t(&frame->uc.uc_sigmask, oldset, failed); >> +#ifndef CONFIG_COMPAT >> + unsafe_copy_siginfo_to_user(&frame->info, &ksig->info, failed); >> +#endif >> >> /* create a stack frame for the caller of the handler */ >> unsafe_put_user(regs->gpr[1], newsp, failed); >> >> user_access_end(); >> >> - if (copy_siginfo_to_user(&frame->info, &ksig->info)) >> +#ifdef CONFIG_COMPAT >> + if (copy_siginfo_to_user32(&frame->info, &ksig->info)) >> goto badframe; >> +#endif >> >> regs->link = tramp; >> >> diff --git a/arch/powerpc/kernel/signal_64.c b/arch/powerpc/kernel/signal_64.c >> index 2cca6c8febe1..82b73fbd937d 100644 >> --- a/arch/powerpc/kernel/signal_64.c >> +++ b/arch/powerpc/kernel/signal_64.c >> @@ -901,15 +901,12 @@ int handle_rt_signal64(struct ksignal *ksig, sigset_t *set, >> } >> >> unsafe_copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set), badframe_block); >> + unsafe_copy_siginfo_to_user(&frame->info, &ksig->info, badframe_block); >> /* Allocate a dummy caller frame for the signal handler. */ >> unsafe_put_user(regs->gpr[1], newsp, badframe_block); >> >> user_write_access_end(); >> >> - /* Save the siginfo outside of the unsafe block. */ >> - if (copy_siginfo_to_user(&frame->info, &ksig->info)) >> - goto badframe; >> - >> /* Make sure signal handler doesn't get spurious FP exceptions */ >> tsk->thread.fp_state.fpscr = 0;
diff --git a/arch/powerpc/kernel/signal_32.c b/arch/powerpc/kernel/signal_32.c index ff101e2b3bab..f9e16d108bc8 100644 --- a/arch/powerpc/kernel/signal_32.c +++ b/arch/powerpc/kernel/signal_32.c @@ -710,12 +710,6 @@ static long restore_tm_user_regs(struct pt_regs *regs, struct mcontext __user *s } #endif -#ifdef CONFIG_PPC64 - -#define copy_siginfo_to_user copy_siginfo_to_user32 - -#endif /* CONFIG_PPC64 */ - /* * Set up a signal frame for a "real-time" signal handler * (one which gets siginfo). @@ -779,14 +773,19 @@ int handle_rt_signal32(struct ksignal *ksig, sigset_t *oldset, asm("dcbst %y0; sync; icbi %y0; sync" :: "Z" (mctx->mc_pad[0])); } unsafe_put_sigset_t(&frame->uc.uc_sigmask, oldset, failed); +#ifndef CONFIG_COMPAT + unsafe_copy_siginfo_to_user(&frame->info, &ksig->info, failed); +#endif /* create a stack frame for the caller of the handler */ unsafe_put_user(regs->gpr[1], newsp, failed); user_access_end(); - if (copy_siginfo_to_user(&frame->info, &ksig->info)) +#ifdef CONFIG_COMPAT + if (copy_siginfo_to_user32(&frame->info, &ksig->info)) goto badframe; +#endif regs->link = tramp; diff --git a/arch/powerpc/kernel/signal_64.c b/arch/powerpc/kernel/signal_64.c index 2cca6c8febe1..82b73fbd937d 100644 --- a/arch/powerpc/kernel/signal_64.c +++ b/arch/powerpc/kernel/signal_64.c @@ -901,15 +901,12 @@ int handle_rt_signal64(struct ksignal *ksig, sigset_t *set, } unsafe_copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set), badframe_block); + unsafe_copy_siginfo_to_user(&frame->info, &ksig->info, badframe_block); /* Allocate a dummy caller frame for the signal handler. */ unsafe_put_user(regs->gpr[1], newsp, badframe_block); user_write_access_end(); - /* Save the siginfo outside of the unsafe block. */ - if (copy_siginfo_to_user(&frame->info, &ksig->info)) - goto badframe; - /* Make sure signal handler doesn't get spurious FP exceptions */ tsk->thread.fp_state.fpscr = 0;
Use unsafe_copy_siginfo_to_user() in order to do the copy within the user access block. On an mpc 8321 (book3s/32) the improvment is about 5% on a process sending a signal to itself. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> --- arch/powerpc/kernel/signal_32.c | 13 ++++++------- arch/powerpc/kernel/signal_64.c | 5 +---- 2 files changed, 7 insertions(+), 11 deletions(-)