From 31019075f41c785eff7f38c62e4c700af019fdb7 Mon Sep 17 00:00:00 2001 From: Joe Perches Date: Tue, 14 Sep 2010 04:23:47 -0400 Subject: [PATCH 01/10] alpha: Use static const char * const where possible Acked-by: Richard Henderson Signed-off-by: Joe Perches Signed-off-by: Matt Turner --- arch/alpha/kernel/err_ev6.c | 12 +++++++----- arch/alpha/kernel/err_marvel.c | 33 ++++++++++++++++---------------- arch/alpha/kernel/err_titan.c | 35 +++++++++++++++++++--------------- arch/alpha/kernel/osf_sys.c | 4 ++-- 4 files changed, 46 insertions(+), 38 deletions(-) diff --git a/arch/alpha/kernel/err_ev6.c b/arch/alpha/kernel/err_ev6.c index 8ca6345bf131..253cf1a87481 100644 --- a/arch/alpha/kernel/err_ev6.c +++ b/arch/alpha/kernel/err_ev6.c @@ -90,11 +90,13 @@ static int ev6_parse_cbox(u64 c_addr, u64 c1_syn, u64 c2_syn, u64 c_stat, u64 c_sts, int print) { - char *sourcename[] = { "UNKNOWN", "UNKNOWN", "UNKNOWN", - "MEMORY", "BCACHE", "DCACHE", - "BCACHE PROBE", "BCACHE PROBE" }; - char *streamname[] = { "D", "I" }; - char *bitsname[] = { "SINGLE", "DOUBLE" }; + static const char * const sourcename[] = { + "UNKNOWN", "UNKNOWN", "UNKNOWN", + "MEMORY", "BCACHE", "DCACHE", + "BCACHE PROBE", "BCACHE PROBE" + }; + static const char * const streamname[] = { "D", "I" }; + static const char * const bitsname[] = { "SINGLE", "DOUBLE" }; int status = MCHK_DISPOSITION_REPORT; int source = -1, stream = -1, bits = -1; diff --git a/arch/alpha/kernel/err_marvel.c b/arch/alpha/kernel/err_marvel.c index 5c905aaaeccd..648ae88aeb8a 100644 --- a/arch/alpha/kernel/err_marvel.c +++ b/arch/alpha/kernel/err_marvel.c @@ -589,22 +589,23 @@ marvel_print_pox_spl_cmplt(u64 spl_cmplt) static void marvel_print_pox_trans_sum(u64 trans_sum) { - char *pcix_cmd[] = { "Interrupt Acknowledge", - "Special Cycle", - "I/O Read", - "I/O Write", - "Reserved", - "Reserved / Device ID Message", - "Memory Read", - "Memory Write", - "Reserved / Alias to Memory Read Block", - "Reserved / Alias to Memory Write Block", - "Configuration Read", - "Configuration Write", - "Memory Read Multiple / Split Completion", - "Dual Address Cycle", - "Memory Read Line / Memory Read Block", - "Memory Write and Invalidate / Memory Write Block" + static const char * const pcix_cmd[] = { + "Interrupt Acknowledge", + "Special Cycle", + "I/O Read", + "I/O Write", + "Reserved", + "Reserved / Device ID Message", + "Memory Read", + "Memory Write", + "Reserved / Alias to Memory Read Block", + "Reserved / Alias to Memory Write Block", + "Configuration Read", + "Configuration Write", + "Memory Read Multiple / Split Completion", + "Dual Address Cycle", + "Memory Read Line / Memory Read Block", + "Memory Write and Invalidate / Memory Write Block" }; #define IO7__POX_TRANSUM__PCI_ADDR__S (0) diff --git a/arch/alpha/kernel/err_titan.c b/arch/alpha/kernel/err_titan.c index f7ed97ce0dfd..c3b3781a03de 100644 --- a/arch/alpha/kernel/err_titan.c +++ b/arch/alpha/kernel/err_titan.c @@ -75,8 +75,12 @@ titan_parse_p_serror(int which, u64 serror, int print) int status = MCHK_DISPOSITION_REPORT; #ifdef CONFIG_VERBOSE_MCHECK - char *serror_src[] = {"GPCI", "APCI", "AGP HP", "AGP LP"}; - char *serror_cmd[] = {"DMA Read", "DMA RMW", "SGTE Read", "Reserved"}; + static const char * const serror_src[] = { + "GPCI", "APCI", "AGP HP", "AGP LP" + }; + static const char * const serror_cmd[] = { + "DMA Read", "DMA RMW", "SGTE Read", "Reserved" + }; #endif /* CONFIG_VERBOSE_MCHECK */ #define TITAN__PCHIP_SERROR__LOST_UECC (1UL << 0) @@ -140,14 +144,15 @@ titan_parse_p_perror(int which, int port, u64 perror, int print) int status = MCHK_DISPOSITION_REPORT; #ifdef CONFIG_VERBOSE_MCHECK - char *perror_cmd[] = { "Interrupt Acknowledge", "Special Cycle", - "I/O Read", "I/O Write", - "Reserved", "Reserved", - "Memory Read", "Memory Write", - "Reserved", "Reserved", - "Configuration Read", "Configuration Write", - "Memory Read Multiple", "Dual Address Cycle", - "Memory Read Line","Memory Write and Invalidate" + static const char * const perror_cmd[] = { + "Interrupt Acknowledge", "Special Cycle", + "I/O Read", "I/O Write", + "Reserved", "Reserved", + "Memory Read", "Memory Write", + "Reserved", "Reserved", + "Configuration Read", "Configuration Write", + "Memory Read Multiple", "Dual Address Cycle", + "Memory Read Line", "Memory Write and Invalidate" }; #endif /* CONFIG_VERBOSE_MCHECK */ @@ -273,11 +278,11 @@ titan_parse_p_agperror(int which, u64 agperror, int print) int cmd, len; unsigned long addr; - char *agperror_cmd[] = { "Read (low-priority)", "Read (high-priority)", - "Write (low-priority)", - "Write (high-priority)", - "Reserved", "Reserved", - "Flush", "Fence" + static const char * const agperror_cmd[] = { + "Read (low-priority)", "Read (high-priority)", + "Write (low-priority)", "Write (high-priority)", + "Reserved", "Reserved", + "Flush", "Fence" }; #endif /* CONFIG_VERBOSE_MCHECK */ diff --git a/arch/alpha/kernel/osf_sys.c b/arch/alpha/kernel/osf_sys.c index 5d1e6d6ce684..16bc1f5df3e2 100644 --- a/arch/alpha/kernel/osf_sys.c +++ b/arch/alpha/kernel/osf_sys.c @@ -594,7 +594,7 @@ SYSCALL_DEFINE2(osf_sigstack, struct sigstack __user *, uss, SYSCALL_DEFINE3(osf_sysinfo, int, command, char __user *, buf, long, count) { - char *sysinfo_table[] = { + const char *sysinfo_table[] = { utsname()->sysname, utsname()->nodename, utsname()->release, @@ -606,7 +606,7 @@ SYSCALL_DEFINE3(osf_sysinfo, int, command, char __user *, buf, long, count) "dummy", /* secure RPC domain */ }; unsigned long offset; - char *res; + const char *res; long len, err = -EINVAL; offset = command-1; From af96f8a340525f24abecc25848a07fff7636a53e Mon Sep 17 00:00:00 2001 From: matt mooney Date: Tue, 14 Sep 2010 05:27:39 -0400 Subject: [PATCH 02/10] alpha: remove unnecessary cast from void* in assignment. Acked-by: Jan-Benedict Glaw Signed-off-by: matt mooney Signed-off-by: Matt Turner --- arch/alpha/kernel/pci-sysfs.c | 2 +- arch/alpha/kernel/srm_env.c | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) diff --git a/arch/alpha/kernel/pci-sysfs.c b/arch/alpha/kernel/pci-sysfs.c index 738fc824e2ea..b899e95f79fd 100644 --- a/arch/alpha/kernel/pci-sysfs.c +++ b/arch/alpha/kernel/pci-sysfs.c @@ -66,7 +66,7 @@ static int pci_mmap_resource(struct kobject *kobj, { struct pci_dev *pdev = to_pci_dev(container_of(kobj, struct device, kobj)); - struct resource *res = (struct resource *)attr->private; + struct resource *res = attr->private; enum pci_mmap_state mmap_type; struct pci_bus_region bar; int i; diff --git a/arch/alpha/kernel/srm_env.c b/arch/alpha/kernel/srm_env.c index 4afc1a1e2e5a..f0df3fbd8402 100644 --- a/arch/alpha/kernel/srm_env.c +++ b/arch/alpha/kernel/srm_env.c @@ -87,7 +87,7 @@ static int srm_env_proc_show(struct seq_file *m, void *v) srm_env_t *entry; char *page; - entry = (srm_env_t *)m->private; + entry = m->private; page = (char *)__get_free_page(GFP_USER); if (!page) return -ENOMEM; From b97f897d60c34adb9a5a37a14033e6a867e86f48 Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Tue, 14 Sep 2010 09:00:22 -0400 Subject: [PATCH 03/10] alpha: fix build breakage in asm/cacheflush.h Alpha SMP flush_icache_user_range() is implemented as an inline function inside include/asm/cacheflush.h. It dereferences @current but doesn't include linux/sched.h and thus causes build failure if linux/sched.h wasn't included previously. Fix it by including the needed header file explicitly. Signed-off-by: Tejun Heo Reported-by: Stephen Rothwell Signed-off-by: Matt Turner --- arch/alpha/include/asm/cacheflush.h | 2 ++ 1 file changed, 2 insertions(+) diff --git a/arch/alpha/include/asm/cacheflush.h b/arch/alpha/include/asm/cacheflush.h index 01d71e1c8a9e..012f1243b1c1 100644 --- a/arch/alpha/include/asm/cacheflush.h +++ b/arch/alpha/include/asm/cacheflush.h @@ -43,6 +43,8 @@ extern void smp_imb(void); /* ??? Ought to use this in arch/alpha/kernel/signal.c too. */ #ifndef CONFIG_SMP +#include + extern void __load_new_mm_context(struct mm_struct *); static inline void flush_icache_user_range(struct vm_area_struct *vma, struct page *page, From 12e750d956eec8b1778679aff705f617095c46c8 Mon Sep 17 00:00:00 2001 From: Arnd Bergmann Date: Tue, 14 Sep 2010 19:34:56 -0400 Subject: [PATCH 04/10] alpha: kill big kernel lock All uses of the BKL on alpha are totally bogus, nothing is really protected by this. Remove the remaining users so we don't have to mark alpha as 'depends on BKL'. Signed-off-by: Arnd Bergmann Cc: Richard Henderson Cc: Ivan Kokshaysky Cc: linux-alpha@vger.kernel.org Signed-off-by: Matt Turner --- arch/alpha/kernel/osf_sys.c | 5 ----- arch/alpha/kernel/traps.c | 3 --- 2 files changed, 8 deletions(-) diff --git a/arch/alpha/kernel/osf_sys.c b/arch/alpha/kernel/osf_sys.c index 16bc1f5df3e2..547e8b84b2f7 100644 --- a/arch/alpha/kernel/osf_sys.c +++ b/arch/alpha/kernel/osf_sys.c @@ -15,7 +15,6 @@ #include #include #include -#include #include #include #include @@ -69,7 +68,6 @@ SYSCALL_DEFINE4(osf_set_program_attributes, unsigned long, text_start, { struct mm_struct *mm; - lock_kernel(); mm = current->mm; mm->end_code = bss_start + bss_len; mm->start_brk = bss_start + bss_len; @@ -78,7 +76,6 @@ SYSCALL_DEFINE4(osf_set_program_attributes, unsigned long, text_start, printk("set_program_attributes(%lx %lx %lx %lx)\n", text_start, text_len, bss_start, bss_len); #endif - unlock_kernel(); return 0; } @@ -517,7 +514,6 @@ SYSCALL_DEFINE2(osf_proplist_syscall, enum pl_code, code, long error; int __user *min_buf_size_ptr; - lock_kernel(); switch (code) { case PL_SET: if (get_user(error, &args->set.nbytes)) @@ -547,7 +543,6 @@ SYSCALL_DEFINE2(osf_proplist_syscall, enum pl_code, code, error = -EOPNOTSUPP; break; }; - unlock_kernel(); return error; } diff --git a/arch/alpha/kernel/traps.c b/arch/alpha/kernel/traps.c index b14f015008ad..0414e021a91c 100644 --- a/arch/alpha/kernel/traps.c +++ b/arch/alpha/kernel/traps.c @@ -13,7 +13,6 @@ #include #include #include -#include #include #include #include @@ -623,7 +622,6 @@ do_entUna(void * va, unsigned long opcode, unsigned long reg, return; } - lock_kernel(); printk("Bad unaligned kernel access at %016lx: %p %lx %lu\n", pc, va, opcode, reg); do_exit(SIGSEGV); @@ -646,7 +644,6 @@ got_exception: * Yikes! No one to forward the exception to. * Since the registers are in a weird format, dump them ourselves. */ - lock_kernel(); printk("%s(%d): unhandled unaligned exception\n", current->comm, task_pid_nr(current)); From 531f0474bf889d489b28ea4b15e87b7cbb77f580 Mon Sep 17 00:00:00 2001 From: Mikael Pettersson Date: Thu, 16 Sep 2010 14:12:55 -0400 Subject: [PATCH 05/10] alpha: wire up fanotify and prlimit64 syscalls The 2.6.36-rc kernel added three new system calls: fanotify_init, fanotify_mark, and prlimit64. This patch wires them up on Alpha. Built and booted on an XP900. Untested beyond that. Signed-off-by: Mikael Pettersson Signed-off-by: Matt Turner --- arch/alpha/include/asm/unistd.h | 5 ++++- arch/alpha/kernel/systbls.S | 3 +++ 2 files changed, 7 insertions(+), 1 deletion(-) diff --git a/arch/alpha/include/asm/unistd.h b/arch/alpha/include/asm/unistd.h index 804e5311c841..9a9672f0a346 100644 --- a/arch/alpha/include/asm/unistd.h +++ b/arch/alpha/include/asm/unistd.h @@ -449,10 +449,13 @@ #define __NR_pwritev 491 #define __NR_rt_tgsigqueueinfo 492 #define __NR_perf_event_open 493 +#define __NR_fanotify_init 494 +#define __NR_fanotify_mark 495 +#define __NR_prlimit64 496 #ifdef __KERNEL__ -#define NR_SYSCALLS 494 +#define NR_SYSCALLS 497 #define __ARCH_WANT_IPC_PARSE_VERSION #define __ARCH_WANT_OLD_READDIR diff --git a/arch/alpha/kernel/systbls.S b/arch/alpha/kernel/systbls.S index 09acb786e72b..ce594ef533cc 100644 --- a/arch/alpha/kernel/systbls.S +++ b/arch/alpha/kernel/systbls.S @@ -512,6 +512,9 @@ sys_call_table: .quad sys_pwritev .quad sys_rt_tgsigqueueinfo .quad sys_perf_event_open + .quad sys_fanotify_init + .quad sys_fanotify_mark /* 495 */ + .quad sys_prlimit64 .size sys_call_table, . - sys_call_table .type sys_call_table, @object From bdc8b8914b17cf97b53e5f7af8168d68cfb089d6 Mon Sep 17 00:00:00 2001 From: Michael Cree Date: Sun, 19 Sep 2010 02:05:40 -0400 Subject: [PATCH 06/10] alpha: Shift perf event pending work earlier in timer interrupt Pending work from the performance event subsystem is executed in the timer interrupt. This patch shifts the call to perf_event_do_pending() before the call to update_process_times() as the latter may call back into the perf event subsystem and it is prudent to have the pending work executed first. Signed-off-by: Michael Cree Signed-off-by: Matt Turner --- arch/alpha/kernel/time.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) diff --git a/arch/alpha/kernel/time.c b/arch/alpha/kernel/time.c index eacceb26d9c8..396af1799ea4 100644 --- a/arch/alpha/kernel/time.c +++ b/arch/alpha/kernel/time.c @@ -191,16 +191,16 @@ irqreturn_t timer_interrupt(int irq, void *dev) write_sequnlock(&xtime_lock); -#ifndef CONFIG_SMP - while (nticks--) - update_process_times(user_mode(get_irq_regs())); -#endif - if (test_perf_event_pending()) { clear_perf_event_pending(); perf_event_do_pending(); } +#ifndef CONFIG_SMP + while (nticks--) + update_process_times(user_mode(get_irq_regs())); +#endif + return IRQ_HANDLED; } From 2deba1bd7126aadb5750beb927c878a6490065e6 Mon Sep 17 00:00:00 2001 From: Al Viro Date: Sat, 18 Sep 2010 08:38:47 -0400 Subject: [PATCH 07/10] alpha: belated ERESTART_RESTARTBLOCK race fix same thing as had been done on other targets back in 2003 - move setting ->restart_block.fn into {rt_,}sigreturn(). Tested-by: Michael Cree Signed-off-by: Al Viro Signed-off-by: Matt Turner --- arch/alpha/kernel/signal.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/arch/alpha/kernel/signal.c b/arch/alpha/kernel/signal.c index 0932dbb1ef8e..e5b1b3c79ff3 100644 --- a/arch/alpha/kernel/signal.c +++ b/arch/alpha/kernel/signal.c @@ -239,6 +239,8 @@ restore_sigcontext(struct sigcontext __user *sc, struct pt_regs *regs, unsigned long usp; long i, err = __get_user(regs->pc, &sc->sc_pc); + current_thread_info()->restart_block.fn = do_no_restart_syscall; + sw->r26 = (unsigned long) ret_from_sys_call; err |= __get_user(regs->r0, sc->sc_regs+0); @@ -591,7 +593,6 @@ syscall_restart(unsigned long r0, unsigned long r19, regs->pc -= 4; break; case ERESTART_RESTARTBLOCK: - current_thread_info()->restart_block.fn = do_no_restart_syscall; regs->r0 = EINTR; break; } From 392fb6e35400edbee183baba24b34a0fa2053813 Mon Sep 17 00:00:00 2001 From: Al Viro Date: Sat, 18 Sep 2010 08:40:07 -0400 Subject: [PATCH 08/10] alpha: unb0rk sigsuspend() and rt_sigsuspend() Old code used to set regs->r0 and regs->r19 to force the right return value. Leaving that after switch to ERESTARTNOHAND was a Bad Idea(tm), since now that screws the restart - if we hit the case when get_signal_to_deliver() returns 0, we will step back to syscall insn, with v0 set to EINTR and a3 to 1. The latter won't matter, since EINTR is 4, aka __NR_write. Testcase: #include #define _GNU_SOURCE #include #include main() { sigset_t mask; sigemptyset(&mask); sigaddset(&mask, SIGCONT); sigprocmask(SIG_SETMASK, &mask, NULL); kill(0, SIGCONT); syscall(__NR_sigsuspend, 1, "b0rken\n", 7); } results on alpha in immediate message to stdout... Fix is obvious; moreover, since we don't need regs anymore, we can switch to normal prototypes for these guys and lose the wrappers. Even better, rt_sigsuspend() is identical to generic version in kernel/signal.c now. Tested-by: Michael Cree Signed-off-by: Al Viro Signed-off-by: Matt Turner --- arch/alpha/include/asm/unistd.h | 1 + arch/alpha/kernel/entry.S | 32 --------------------------- arch/alpha/kernel/signal.c | 38 +-------------------------------- 3 files changed, 2 insertions(+), 69 deletions(-) diff --git a/arch/alpha/include/asm/unistd.h b/arch/alpha/include/asm/unistd.h index 9a9672f0a346..058937bf5a77 100644 --- a/arch/alpha/include/asm/unistd.h +++ b/arch/alpha/include/asm/unistd.h @@ -466,6 +466,7 @@ #define __ARCH_WANT_SYS_OLD_GETRLIMIT #define __ARCH_WANT_SYS_OLDUMOUNT #define __ARCH_WANT_SYS_SIGPENDING +#define __ARCH_WANT_SYS_RT_SIGSUSPEND /* "Conditional" syscalls. What we want is diff --git a/arch/alpha/kernel/entry.S b/arch/alpha/kernel/entry.S index b45d913a51c3..bceb325fd4c5 100644 --- a/arch/alpha/kernel/entry.S +++ b/arch/alpha/kernel/entry.S @@ -778,38 +778,6 @@ sys_rt_sigreturn: br ret_from_sys_call .end sys_rt_sigreturn - .align 4 - .globl sys_sigsuspend - .ent sys_sigsuspend -sys_sigsuspend: - .prologue 0 - mov $sp, $17 - br $1, do_switch_stack - mov $sp, $18 - subq $sp, 16, $sp - stq $26, 0($sp) - jsr $26, do_sigsuspend - ldq $26, 0($sp) - lda $sp, SWITCH_STACK_SIZE+16($sp) - ret -.end sys_sigsuspend - - .align 4 - .globl sys_rt_sigsuspend - .ent sys_rt_sigsuspend -sys_rt_sigsuspend: - .prologue 0 - mov $sp, $18 - br $1, do_switch_stack - mov $sp, $19 - subq $sp, 16, $sp - stq $26, 0($sp) - jsr $26, do_rt_sigsuspend - ldq $26, 0($sp) - lda $sp, SWITCH_STACK_SIZE+16($sp) - ret -.end sys_rt_sigsuspend - .align 4 .globl sys_sethae .ent sys_sethae diff --git a/arch/alpha/kernel/signal.c b/arch/alpha/kernel/signal.c index e5b1b3c79ff3..0f6b51ae865a 100644 --- a/arch/alpha/kernel/signal.c +++ b/arch/alpha/kernel/signal.c @@ -144,8 +144,7 @@ SYSCALL_DEFINE5(rt_sigaction, int, sig, const struct sigaction __user *, act, /* * Atomically swap in the new signal mask, and wait for a signal. */ -asmlinkage int -do_sigsuspend(old_sigset_t mask, struct pt_regs *regs, struct switch_stack *sw) +SYSCALL_DEFINE1(sigsuspend, old_sigset_t, mask) { mask &= _BLOCKABLE; spin_lock_irq(¤t->sighand->siglock); @@ -154,41 +153,6 @@ do_sigsuspend(old_sigset_t mask, struct pt_regs *regs, struct switch_stack *sw) recalc_sigpending(); spin_unlock_irq(¤t->sighand->siglock); - /* Indicate EINTR on return from any possible signal handler, - which will not come back through here, but via sigreturn. */ - regs->r0 = EINTR; - regs->r19 = 1; - - current->state = TASK_INTERRUPTIBLE; - schedule(); - set_thread_flag(TIF_RESTORE_SIGMASK); - return -ERESTARTNOHAND; -} - -asmlinkage int -do_rt_sigsuspend(sigset_t __user *uset, size_t sigsetsize, - struct pt_regs *regs, struct switch_stack *sw) -{ - sigset_t set; - - /* XXX: Don't preclude handling different sized sigset_t's. */ - if (sigsetsize != sizeof(sigset_t)) - return -EINVAL; - if (copy_from_user(&set, uset, sizeof(set))) - return -EFAULT; - - sigdelsetmask(&set, ~_BLOCKABLE); - spin_lock_irq(¤t->sighand->siglock); - current->saved_sigmask = current->blocked; - current->blocked = set; - recalc_sigpending(); - spin_unlock_irq(¤t->sighand->siglock); - - /* Indicate EINTR on return from any possible signal handler, - which will not come back through here, but via sigreturn. */ - regs->r0 = EINTR; - regs->r19 = 1; - current->state = TASK_INTERRUPTIBLE; schedule(); set_thread_flag(TIF_RESTORE_SIGMASK); From 53293638618f1a8b0b182dfedaab08b28930f992 Mon Sep 17 00:00:00 2001 From: Al Viro Date: Sat, 18 Sep 2010 08:41:16 -0400 Subject: [PATCH 09/10] alpha: fix a 14 years old bug in sigreturn tracing The way sigreturn() is implemented on alpha breaks PTRACE_SYSCALL, all way back to 1.3.95 when alpha has grown PTRACE_SYSCALL support. What happens is direct return to ret_from_syscall, in order to bypass mangling of a3 (error indicator) and prevent other mutilations of registers (e.g. by syscall restart). That's fine, but... the entire TIF_SYSCALL_TRACE codepath is kept separate on alpha and post-syscall stopping/notifying the tracer is after the syscall. And the normal path we are forcibly switching to doesn't have it. So we end up with *one* stop in traced sigreturn() vs. two in other syscalls. And yes, strace is visibly broken by that; try to strace the following #include #include void f(int sig) {} main() { signal(SIGHUP, f); raise(SIGHUP); write(1, "eeeek\n", 6); } and watch the show. The close(1) = 405 in the end of strace output is coming from return value of write() (6 == __NR_close on alpha) and syscall number of exit_group() (__NR_exit_group == 405 there). The fix is fairly simple - the only thing we end up missing is the call of syscall_trace() and we can tell whether we'd been called from the SYSCALL_TRACE path by checking ra value. Since we are setting the switch_stack up (that's what sys_sigreturn() does), we have the right environment for calling syscall_trace() - just before we call undo_switch_stack() and return. Since undo_switch_stack() will overwrite s0 anyway, we can use it to store the result of "has it been called from SYSCALL_TRACE path?" check. The same thing applies in rt_sigreturn(). Tested-by: Michael Cree Signed-off-by: Al Viro Signed-off-by: Matt Turner --- arch/alpha/kernel/entry.S | 13 +++++++++++-- 1 file changed, 11 insertions(+), 2 deletions(-) diff --git a/arch/alpha/kernel/entry.S b/arch/alpha/kernel/entry.S index bceb325fd4c5..a3e9cd85cfee 100644 --- a/arch/alpha/kernel/entry.S +++ b/arch/alpha/kernel/entry.S @@ -430,6 +430,7 @@ strace: beq $1, 1f ldq $27, 0($2) 1: jsr $26, ($27), sys_gettimeofday +ret_from_straced: ldgp $gp, 0($26) /* check return.. */ @@ -757,11 +758,15 @@ sys_vfork: .ent sys_sigreturn sys_sigreturn: .prologue 0 + lda $9, ret_from_straced + cmpult $26, $9, $9 mov $sp, $17 lda $18, -SWITCH_STACK_SIZE($sp) lda $sp, -SWITCH_STACK_SIZE($sp) jsr $26, do_sigreturn - br $1, undo_switch_stack + bne $9, 1f + jsr $26, syscall_trace +1: br $1, undo_switch_stack br ret_from_sys_call .end sys_sigreturn @@ -770,11 +775,15 @@ sys_sigreturn: .ent sys_rt_sigreturn sys_rt_sigreturn: .prologue 0 + lda $9, ret_from_straced + cmpult $26, $9, $9 mov $sp, $17 lda $18, -SWITCH_STACK_SIZE($sp) lda $sp, -SWITCH_STACK_SIZE($sp) jsr $26, do_rt_sigreturn - br $1, undo_switch_stack + bne $9, 1f + jsr $26, syscall_trace +1: br $1, undo_switch_stack br ret_from_sys_call .end sys_rt_sigreturn From 494486a1d2697f2153199b6501ab5b4d6e15a2bb Mon Sep 17 00:00:00 2001 From: Al Viro Date: Sat, 18 Sep 2010 08:42:27 -0400 Subject: [PATCH 10/10] alpha: deal with multiple simultaneously pending signals Unlike the other targets, alpha sets _one_ sigframe and buggers off until the next syscall/interrupt, even if more signals are pending. It leads to quite a few unpleasant inconsistencies, starting with SIGSEGV potentially arriving not where it should and including e.g. mess with sigsuspend(); consider two pending signals blocked until sigsuspend() unblocks them. We pick the first one; then, if we are hit by interrupt while in the handler, we process the second one as well. If we are not, and if no syscalls had been made, we get out of the first handler and leave the second signal pending; normally sigreturn() would've picked it anyway, but here it starts with restoring the original mask and voila - the second signal is blocked again. On everything else we get both delivered consistently. It's actually easy to fix; the only thing to watch out for is prevention of double syscall restart. Fortunately, the idea I've nicked from arm fix by rmk works just fine... Testcase demonstrating the behaviour in question; on alpha we get one or both flags set (usually one), on everything else both are always set. #include #include int had1, had2; void f1(int sig) { had1 = 1; } void f2(int sig) { had2 = 1; } main() { sigset_t set1, set2; sigemptyset(&set1); sigemptyset(&set2); sigaddset(&set2, 1); sigaddset(&set2, 2); signal(1, f1); signal(2, f2); sigprocmask(SIG_SETMASK, &set2, NULL); raise(1); raise(2); sigsuspend(&set1); printf("had1:%d had2:%d\n", had1, had2); } Tested-by: Michael Cree Signed-off-by: Al Viro Signed-off-by: Matt Turner --- arch/alpha/kernel/entry.S | 16 +++++++++++----- 1 file changed, 11 insertions(+), 5 deletions(-) diff --git a/arch/alpha/kernel/entry.S b/arch/alpha/kernel/entry.S index a3e9cd85cfee..ab1ee0ab082b 100644 --- a/arch/alpha/kernel/entry.S +++ b/arch/alpha/kernel/entry.S @@ -317,14 +317,14 @@ ret_from_sys_call: ldq $0, SP_OFF($sp) and $0, 8, $0 beq $0, restore_all -ret_from_reschedule: +ret_to_user: /* Make sure need_resched and sigpending don't change between sampling and the rti. */ lda $16, 7 call_pal PAL_swpipl ldl $5, TI_FLAGS($8) and $5, _TIF_WORK_MASK, $2 - bne $5, work_pending + bne $2, work_pending restore_all: RESTORE_ALL call_pal PAL_rti @@ -363,7 +363,7 @@ $ret_success: * $8: current. * $19: The old syscall number, or zero if this is not a return * from a syscall that errored and is possibly restartable. - * $20: Error indication. + * $20: The old a3 value */ .align 4 @@ -392,12 +392,18 @@ $work_resched: $work_notifysig: mov $sp, $16 - br $1, do_switch_stack + bsr $1, do_switch_stack mov $sp, $17 mov $5, $18 + mov $19, $9 /* save old syscall number */ + mov $20, $10 /* save old a3 */ + and $5, _TIF_SIGPENDING, $2 + cmovne $2, 0, $9 /* we don't want double syscall restarts */ jsr $26, do_notify_resume + mov $9, $19 + mov $10, $20 bsr $1, undo_switch_stack - br restore_all + br ret_to_user .end work_pending /*