| Message ID | 4b7058eb0f5558fb7e2cee1b8f7cf99ebd03084e.1584620202.git.msuchanek@suse.de (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Disable compat cruft on ppc64le v11 | expand |
Michal Suchanek's on March 19, 2020 10:19 pm: > diff --git a/arch/powerpc/kernel/signal.c b/arch/powerpc/kernel/signal.c > index 4b0152108f61..a264989626fd 100644 > --- a/arch/powerpc/kernel/signal.c > +++ b/arch/powerpc/kernel/signal.c > @@ -247,7 +247,6 @@ static void do_signal(struct task_struct *tsk) > sigset_t *oldset = sigmask_to_save(); > struct ksignal ksig = { .sig = 0 }; > int ret; > - int is32 = is_32bit_task(); > > BUG_ON(tsk != current); > > @@ -277,7 +276,7 @@ static void do_signal(struct task_struct *tsk) > > rseq_signal_deliver(&ksig, tsk->thread.regs); > > - if (is32) { > + if (is_32bit_task()) { > if (ksig.ka.sa.sa_flags & SA_SIGINFO) > ret = handle_rt_signal32(&ksig, oldset, tsk); > else Unnecessary? > diff --git a/arch/powerpc/kernel/syscall_64.c b/arch/powerpc/kernel/syscall_64.c > index 87d95b455b83..2dcbfe38f5ac 100644 > --- a/arch/powerpc/kernel/syscall_64.c > +++ b/arch/powerpc/kernel/syscall_64.c > @@ -24,7 +24,6 @@ notrace long system_call_exception(long r3, long r4, long r5, > long r6, long r7, long r8, > unsigned long r0, struct pt_regs *regs) > { > - unsigned long ti_flags; > syscall_fn f; > > if (IS_ENABLED(CONFIG_PPC_IRQ_SOFT_MASK_DEBUG)) > @@ -68,8 +67,7 @@ notrace long system_call_exception(long r3, long r4, long r5, > > local_irq_enable(); > > - ti_flags = current_thread_info()->flags; > - if (unlikely(ti_flags & _TIF_SYSCALL_DOTRACE)) { > + if (unlikely(current_thread_info()->flags & _TIF_SYSCALL_DOTRACE)) { > /* > * We use the return value of do_syscall_trace_enter() as the > * syscall number. If the syscall was rejected for any reason > @@ -94,7 +92,7 @@ notrace long system_call_exception(long r3, long r4, long r5, > /* May be faster to do array_index_nospec? */ > barrier_nospec(); > > - if (unlikely(ti_flags & _TIF_32BIT)) { > + if (unlikely(is_32bit_task())) { Problem is, does this allow the load of ti_flags to be used for both tests, or does test_bit make it re-load? This could maybe be fixed by testing if(IS_ENABLED(CONFIG_COMPAT) && Other than these, the patches all look pretty good to me. Thanks, Nick
On Tue, Mar 24, 2020 at 06:54:20PM +1000, Nicholas Piggin wrote: > Michal Suchanek's on March 19, 2020 10:19 pm: > > diff --git a/arch/powerpc/kernel/signal.c b/arch/powerpc/kernel/signal.c > > index 4b0152108f61..a264989626fd 100644 > > --- a/arch/powerpc/kernel/signal.c > > +++ b/arch/powerpc/kernel/signal.c > > @@ -247,7 +247,6 @@ static void do_signal(struct task_struct *tsk) > > sigset_t *oldset = sigmask_to_save(); > > struct ksignal ksig = { .sig = 0 }; > > int ret; > > - int is32 = is_32bit_task(); > > > > BUG_ON(tsk != current); > > > > @@ -277,7 +276,7 @@ static void do_signal(struct task_struct *tsk) > > > > rseq_signal_deliver(&ksig, tsk->thread.regs); > > > > - if (is32) { > > + if (is_32bit_task()) { > > if (ksig.ka.sa.sa_flags & SA_SIGINFO) > > ret = handle_rt_signal32(&ksig, oldset, tsk); > > else > > Unnecessary? > > > diff --git a/arch/powerpc/kernel/syscall_64.c b/arch/powerpc/kernel/syscall_64.c > > index 87d95b455b83..2dcbfe38f5ac 100644 > > --- a/arch/powerpc/kernel/syscall_64.c > > +++ b/arch/powerpc/kernel/syscall_64.c > > @@ -24,7 +24,6 @@ notrace long system_call_exception(long r3, long r4, long r5, > > long r6, long r7, long r8, > > unsigned long r0, struct pt_regs *regs) > > { > > - unsigned long ti_flags; > > syscall_fn f; > > > > if (IS_ENABLED(CONFIG_PPC_IRQ_SOFT_MASK_DEBUG)) > > @@ -68,8 +67,7 @@ notrace long system_call_exception(long r3, long r4, long r5, > > > > local_irq_enable(); > > > > - ti_flags = current_thread_info()->flags; > > - if (unlikely(ti_flags & _TIF_SYSCALL_DOTRACE)) { > > + if (unlikely(current_thread_info()->flags & _TIF_SYSCALL_DOTRACE)) { > > /* > > * We use the return value of do_syscall_trace_enter() as the > > * syscall number. If the syscall was rejected for any reason > > @@ -94,7 +92,7 @@ notrace long system_call_exception(long r3, long r4, long r5, > > /* May be faster to do array_index_nospec? */ > > barrier_nospec(); > > > > - if (unlikely(ti_flags & _TIF_32BIT)) { > > + if (unlikely(is_32bit_task())) { > > Problem is, does this allow the load of ti_flags to be used for both > tests, or does test_bit make it re-load? > > This could maybe be fixed by testing if(IS_ENABLED(CONFIG_COMPAT) && Both points already discussed here: https://lore.kernel.org/linuxppc-dev/13fa324dc879a7f325290bf2e131b87eb491cd7b.1573576649.git.msuchanek@suse.de/ Thanks Michal
Michal Suchánek's on March 25, 2020 5:30 am: > On Tue, Mar 24, 2020 at 06:54:20PM +1000, Nicholas Piggin wrote: >> Michal Suchanek's on March 19, 2020 10:19 pm: >> > diff --git a/arch/powerpc/kernel/signal.c b/arch/powerpc/kernel/signal.c >> > index 4b0152108f61..a264989626fd 100644 >> > --- a/arch/powerpc/kernel/signal.c >> > +++ b/arch/powerpc/kernel/signal.c >> > @@ -247,7 +247,6 @@ static void do_signal(struct task_struct *tsk) >> > sigset_t *oldset = sigmask_to_save(); >> > struct ksignal ksig = { .sig = 0 }; >> > int ret; >> > - int is32 = is_32bit_task(); >> > >> > BUG_ON(tsk != current); >> > >> > @@ -277,7 +276,7 @@ static void do_signal(struct task_struct *tsk) >> > >> > rseq_signal_deliver(&ksig, tsk->thread.regs); >> > >> > - if (is32) { >> > + if (is_32bit_task()) { >> > if (ksig.ka.sa.sa_flags & SA_SIGINFO) >> > ret = handle_rt_signal32(&ksig, oldset, tsk); >> > else >> >> Unnecessary? >> >> > diff --git a/arch/powerpc/kernel/syscall_64.c b/arch/powerpc/kernel/syscall_64.c >> > index 87d95b455b83..2dcbfe38f5ac 100644 >> > --- a/arch/powerpc/kernel/syscall_64.c >> > +++ b/arch/powerpc/kernel/syscall_64.c >> > @@ -24,7 +24,6 @@ notrace long system_call_exception(long r3, long r4, long r5, >> > long r6, long r7, long r8, >> > unsigned long r0, struct pt_regs *regs) >> > { >> > - unsigned long ti_flags; >> > syscall_fn f; >> > >> > if (IS_ENABLED(CONFIG_PPC_IRQ_SOFT_MASK_DEBUG)) >> > @@ -68,8 +67,7 @@ notrace long system_call_exception(long r3, long r4, long r5, >> > >> > local_irq_enable(); >> > >> > - ti_flags = current_thread_info()->flags; >> > - if (unlikely(ti_flags & _TIF_SYSCALL_DOTRACE)) { >> > + if (unlikely(current_thread_info()->flags & _TIF_SYSCALL_DOTRACE)) { >> > /* >> > * We use the return value of do_syscall_trace_enter() as the >> > * syscall number. If the syscall was rejected for any reason >> > @@ -94,7 +92,7 @@ notrace long system_call_exception(long r3, long r4, long r5, >> > /* May be faster to do array_index_nospec? */ >> > barrier_nospec(); >> > >> > - if (unlikely(ti_flags & _TIF_32BIT)) { >> > + if (unlikely(is_32bit_task())) { >> >> Problem is, does this allow the load of ti_flags to be used for both >> tests, or does test_bit make it re-load? >> >> This could maybe be fixed by testing if(IS_ENABLED(CONFIG_COMPAT) && > Both points already discussed here: Agh, I'm hopeless. I don't think it really resolves this issue. But probably don't have time to look at generated asm, and might never because it won't really hit LE unless we add a 32-bit ABI. It's pretty minor though either way. Sorry for being difficult, I really do like your patches :) Thanks, Nick
diff --git a/arch/powerpc/include/asm/thread_info.h b/arch/powerpc/include/asm/thread_info.h index a2270749b282..ca6c97025704 100644 --- a/arch/powerpc/include/asm/thread_info.h +++ b/arch/powerpc/include/asm/thread_info.h @@ -162,10 +162,10 @@ static inline bool test_thread_local_flags(unsigned int flags) return (ti->local_flags & flags) != 0; } -#ifdef CONFIG_PPC64 +#ifdef CONFIG_COMPAT #define is_32bit_task() (test_thread_flag(TIF_32BIT)) #else -#define is_32bit_task() (1) +#define is_32bit_task() (IS_ENABLED(CONFIG_PPC32)) #endif #if defined(CONFIG_PPC64) diff --git a/arch/powerpc/kernel/Makefile b/arch/powerpc/kernel/Makefile index 5700231a8988..98a1c143b613 100644 --- a/arch/powerpc/kernel/Makefile +++ b/arch/powerpc/kernel/Makefile @@ -42,16 +42,16 @@ CFLAGS_btext.o += -DDISABLE_BRANCH_PROFILING endif obj-y := cputable.o ptrace.o syscalls.o \ - irq.o align.o signal_32.o pmc.o vdso.o \ + irq.o align.o signal_$(BITS).o pmc.o vdso.o \ process.o systbl.o idle.o \ signal.o sysfs.o cacheinfo.o time.o \ prom.o traps.o setup-common.o \ udbg.o misc.o io.o misc_$(BITS).o \ of_platform.o prom_parse.o -obj-$(CONFIG_PPC64) += setup_64.o sys_ppc32.o \ - signal_64.o ptrace32.o \ +obj-$(CONFIG_PPC64) += setup_64.o \ paca.o nvram_64.o firmware.o note.o \ syscall_64.o +obj-$(CONFIG_COMPAT) += sys_ppc32.o ptrace32.o signal_32.o obj-$(CONFIG_VDSO32) += vdso32/ obj-$(CONFIG_PPC_WATCHDOG) += watchdog.o obj-$(CONFIG_HAVE_HW_BREAKPOINT) += hw_breakpoint.o diff --git a/arch/powerpc/kernel/entry_64.S b/arch/powerpc/kernel/entry_64.S index 4c0d0400e93d..fe1421e08f09 100644 --- a/arch/powerpc/kernel/entry_64.S +++ b/arch/powerpc/kernel/entry_64.S @@ -52,8 +52,10 @@ SYS_CALL_TABLE: .tc sys_call_table[TC],sys_call_table +#ifdef CONFIG_COMPAT COMPAT_SYS_CALL_TABLE: .tc compat_sys_call_table[TC],compat_sys_call_table +#endif /* This value is used to mark exception frames on the stack. */ exception_marker: diff --git a/arch/powerpc/kernel/signal.c b/arch/powerpc/kernel/signal.c index 4b0152108f61..a264989626fd 100644 --- a/arch/powerpc/kernel/signal.c +++ b/arch/powerpc/kernel/signal.c @@ -247,7 +247,6 @@ static void do_signal(struct task_struct *tsk) sigset_t *oldset = sigmask_to_save(); struct ksignal ksig = { .sig = 0 }; int ret; - int is32 = is_32bit_task(); BUG_ON(tsk != current); @@ -277,7 +276,7 @@ static void do_signal(struct task_struct *tsk) rseq_signal_deliver(&ksig, tsk->thread.regs); - if (is32) { + if (is_32bit_task()) { if (ksig.ka.sa.sa_flags & SA_SIGINFO) ret = handle_rt_signal32(&ksig, oldset, tsk); else diff --git a/arch/powerpc/kernel/syscall_64.c b/arch/powerpc/kernel/syscall_64.c index 87d95b455b83..2dcbfe38f5ac 100644 --- a/arch/powerpc/kernel/syscall_64.c +++ b/arch/powerpc/kernel/syscall_64.c @@ -24,7 +24,6 @@ notrace long system_call_exception(long r3, long r4, long r5, long r6, long r7, long r8, unsigned long r0, struct pt_regs *regs) { - unsigned long ti_flags; syscall_fn f; if (IS_ENABLED(CONFIG_PPC_IRQ_SOFT_MASK_DEBUG)) @@ -68,8 +67,7 @@ notrace long system_call_exception(long r3, long r4, long r5, local_irq_enable(); - ti_flags = current_thread_info()->flags; - if (unlikely(ti_flags & _TIF_SYSCALL_DOTRACE)) { + if (unlikely(current_thread_info()->flags & _TIF_SYSCALL_DOTRACE)) { /* * We use the return value of do_syscall_trace_enter() as the * syscall number. If the syscall was rejected for any reason @@ -94,7 +92,7 @@ notrace long system_call_exception(long r3, long r4, long r5, /* May be faster to do array_index_nospec? */ barrier_nospec(); - if (unlikely(ti_flags & _TIF_32BIT)) { + if (unlikely(is_32bit_task())) { f = (void *)compat_sys_call_table[r0]; r3 &= 0x00000000ffffffffULL; diff --git a/arch/powerpc/kernel/vdso.c b/arch/powerpc/kernel/vdso.c index b9a108411c0d..77da3b7d304d 100644 --- a/arch/powerpc/kernel/vdso.c +++ b/arch/powerpc/kernel/vdso.c @@ -656,7 +656,8 @@ static void __init vdso_setup_syscall_map(void) if (sys_call_table[i] != sys_ni_syscall) vdso_data->syscall_map_64[i >> 5] |= 0x80000000UL >> (i & 0x1f); - if (compat_sys_call_table[i] != sys_ni_syscall) + if (IS_ENABLED(CONFIG_COMPAT) && + compat_sys_call_table[i] != sys_ni_syscall) vdso_data->syscall_map_32[i >> 5] |= 0x80000000UL >> (i & 0x1f); #else /* CONFIG_PPC64 */ diff --git a/arch/powerpc/perf/callchain.c b/arch/powerpc/perf/callchain.c index 194c7fd933e6..8a274bd523b1 100644 --- a/arch/powerpc/perf/callchain.c +++ b/arch/powerpc/perf/callchain.c @@ -15,7 +15,7 @@ #include <asm/sigcontext.h> #include <asm/ucontext.h> #include <asm/vdso.h> -#ifdef CONFIG_PPC64 +#ifdef CONFIG_COMPAT #include "../kernel/ppc32.h" #endif #include <asm/pte-walk.h> @@ -285,6 +285,7 @@ static inline void perf_callchain_user_64(struct perf_callchain_entry_ctx *entry #endif /* CONFIG_PPC64 */ +#if defined(CONFIG_PPC32) || defined(CONFIG_COMPAT) /* * On 32-bit we just access the address and let hash_page create a * HPTE if necessary, so there is no need to fall back to reading @@ -448,6 +449,11 @@ static void perf_callchain_user_32(struct perf_callchain_entry_ctx *entry, sp = next_sp; } } +#else /* 32bit */ +static void perf_callchain_user_32(struct perf_callchain_entry_ctx *entry, + struct pt_regs *regs) +{} +#endif /* 32bit */ void perf_callchain_user(struct perf_callchain_entry_ctx *entry, struct pt_regs *regs)
There are numerous references to 32bit functions in generic and 64bit code so ifdef them out. Signed-off-by: Michal Suchanek <msuchanek@suse.de> --- v2: - fix 32bit ifdef condition in signal.c - simplify the compat ifdef condition in vdso.c - 64bit is redundant - simplify the compat ifdef condition in callchain.c - 64bit is redundant v3: - use IS_ENABLED and maybe_unused where possible - do not ifdef declarations - clean up Makefile v4: - further makefile cleanup - simplify is_32bit_task conditions - avoid ifdef in condition by using return v5: - avoid unreachable code on 32bit - make is_current_64bit constant on !COMPAT - add stub perf_callchain_user_32 to avoid some ifdefs v6: - consolidate current_is_64bit v7: - remove leftover perf_callchain_user_32 stub from previous series version v8: - fix build again - too trigger-happy with stub removal - remove a vdso.c hunk that causes warning according to kbuild test robot v9: - removed current_is_64bit in previous patch v10: - rebase on top of 70ed86f4de5bd --- arch/powerpc/include/asm/thread_info.h | 4 ++-- arch/powerpc/kernel/Makefile | 6 +++--- arch/powerpc/kernel/entry_64.S | 2 ++ arch/powerpc/kernel/signal.c | 3 +-- arch/powerpc/kernel/syscall_64.c | 6 ++---- arch/powerpc/kernel/vdso.c | 3 ++- arch/powerpc/perf/callchain.c | 8 +++++++- 7 files changed, 19 insertions(+), 13 deletions(-)