From: Oleg Nesterov oleg@redhat.com
commit 5abbe51a526253b9f003e9a0a195638dc882d660 upstream.
Preparation for fixing get_nr_restart_syscall() on X86 for COMPAT.
Add a new helper which sets restart_block->fn and calls a dummy arch_set_restart_data() helper.
Fixes: 609c19a385c8 ("x86/ptrace: Stop setting TS_COMPAT in ptrace code") Signed-off-by: Oleg Nesterov oleg@redhat.com Signed-off-by: Thomas Gleixner tglx@linutronix.de Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20210201174641.GA17871@redhat.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- fs/select.c | 10 ++++------ include/linux/thread_info.h | 13 +++++++++++++ kernel/futex.c | 3 +-- kernel/time/alarmtimer.c | 2 +- kernel/time/hrtimer.c | 2 +- kernel/time/posix-cpu-timers.c | 2 +- 6 files changed, 21 insertions(+), 11 deletions(-)
--- a/fs/select.c +++ b/fs/select.c @@ -1055,10 +1055,9 @@ static long do_restart_poll(struct resta
ret = do_sys_poll(ufds, nfds, to);
- if (ret == -ERESTARTNOHAND) { - restart_block->fn = do_restart_poll; - ret = -ERESTART_RESTARTBLOCK; - } + if (ret == -ERESTARTNOHAND) + ret = set_restart_fn(restart_block, do_restart_poll); + return ret; }
@@ -1080,7 +1079,6 @@ SYSCALL_DEFINE3(poll, struct pollfd __us struct restart_block *restart_block;
restart_block = ¤t->restart_block; - restart_block->fn = do_restart_poll; restart_block->poll.ufds = ufds; restart_block->poll.nfds = nfds;
@@ -1091,7 +1089,7 @@ SYSCALL_DEFINE3(poll, struct pollfd __us } else restart_block->poll.has_timeout = 0;
- ret = -ERESTART_RESTARTBLOCK; + ret = set_restart_fn(restart_block, do_restart_poll); } return ret; } --- a/include/linux/thread_info.h +++ b/include/linux/thread_info.h @@ -11,6 +11,7 @@ #include <linux/types.h> #include <linux/bug.h> #include <linux/restart_block.h> +#include <linux/errno.h>
#ifdef CONFIG_THREAD_INFO_IN_TASK /* @@ -59,6 +60,18 @@ enum syscall_work_bit {
#ifdef __KERNEL__
+#ifndef arch_set_restart_data +#define arch_set_restart_data(restart) do { } while (0) +#endif + +static inline long set_restart_fn(struct restart_block *restart, + long (*fn)(struct restart_block *)) +{ + restart->fn = fn; + arch_set_restart_data(restart); + return -ERESTART_RESTARTBLOCK; +} + #ifndef THREAD_ALIGN #define THREAD_ALIGN THREAD_SIZE #endif --- a/kernel/futex.c +++ b/kernel/futex.c @@ -2728,14 +2728,13 @@ retry: goto out;
restart = ¤t->restart_block; - restart->fn = futex_wait_restart; restart->futex.uaddr = uaddr; restart->futex.val = val; restart->futex.time = *abs_time; restart->futex.bitset = bitset; restart->futex.flags = flags | FLAGS_HAS_TIMEOUT;
- ret = -ERESTART_RESTARTBLOCK; + ret = set_restart_fn(restart, futex_wait_restart);
out: if (to) { --- a/kernel/time/alarmtimer.c +++ b/kernel/time/alarmtimer.c @@ -848,9 +848,9 @@ static int alarm_timer_nsleep(const cloc if (flags == TIMER_ABSTIME) return -ERESTARTNOHAND;
- restart->fn = alarm_timer_nsleep_restart; restart->nanosleep.clockid = type; restart->nanosleep.expires = exp; + set_restart_fn(restart, alarm_timer_nsleep_restart); return ret; }
--- a/kernel/time/hrtimer.c +++ b/kernel/time/hrtimer.c @@ -1957,9 +1957,9 @@ long hrtimer_nanosleep(ktime_t rqtp, con }
restart = ¤t->restart_block; - restart->fn = hrtimer_nanosleep_restart; restart->nanosleep.clockid = t.timer.base->clockid; restart->nanosleep.expires = hrtimer_get_expires_tv64(&t.timer); + set_restart_fn(restart, hrtimer_nanosleep_restart); out: destroy_hrtimer_on_stack(&t.timer); return ret; --- a/kernel/time/posix-cpu-timers.c +++ b/kernel/time/posix-cpu-timers.c @@ -1480,8 +1480,8 @@ static int posix_cpu_nsleep(const clocki if (flags & TIMER_ABSTIME) return -ERESTARTNOHAND;
- restart_block->fn = posix_cpu_nsleep_restart; restart_block->nanosleep.clockid = which_clock; + set_restart_fn(restart_block, posix_cpu_nsleep_restart); } return error; }