On Tue, May 29, 2012 at 12:55:10AM -0400, Matt Turner wrote: > I recently looked at this gentoo bug -- > https://bugs.gentoo.org/show_bug.cgi?id=405829 and then came across > this email and the two patches. They seem possibly related. > > It looks like Al said he thought he had a better way of fixing the > problem, but then I'm not sure if his patches surfaced or not. > > Also possibly related, Tobias and Michael have seen some RCU stalls > with recent kernels. Looks like getxpid needs an update? Umm... Let me see if I can find it... Here: alpha: take a bunch of syscalls into osf_sys.c New helper: current_thread_info(). Allows to do a bunch of odd syscalls in C. While we are at it, there had never been a reason to do osf_getpriority() in assembler. We also get "namespace"-aware (read: consistent with getuid(2), etc.) behaviour from getx?id() syscalls now. Signed-off-by: Al Viro <viro@xxxxxxxxxxxxxxxxxx> diff --git a/arch/alpha/include/asm/ptrace.h b/arch/alpha/include/asm/ptrace.h index fd698a1..b87755a 100644 --- a/arch/alpha/include/asm/ptrace.h +++ b/arch/alpha/include/asm/ptrace.h @@ -76,7 +76,10 @@ struct switch_stack { #define task_pt_regs(task) \ ((struct pt_regs *) (task_stack_page(task) + 2*PAGE_SIZE) - 1) -#define force_successful_syscall_return() (task_pt_regs(current)->r0 = 0) +#define current_pt_regs() \ + ((struct pt_regs *) ((char *)current_thread_info() + 2*PAGE_SIZE) - 1) + +#define force_successful_syscall_return() (current_pt_regs()->r0 = 0) #endif diff --git a/arch/alpha/kernel/entry.S b/arch/alpha/kernel/entry.S index 6d159ce..22b0c4d 100644 --- a/arch/alpha/kernel/entry.S +++ b/arch/alpha/kernel/entry.S @@ -797,115 +797,6 @@ sys_rt_sigreturn: .end sys_rt_sigreturn .align 4 - .globl sys_sethae - .ent sys_sethae -sys_sethae: - .prologue 0 - stq $16, 152($sp) - ret -.end sys_sethae - - .align 4 - .globl osf_getpriority - .ent osf_getpriority -osf_getpriority: - lda $sp, -16($sp) - stq $26, 0($sp) - .prologue 0 - - jsr $26, sys_getpriority - - ldq $26, 0($sp) - blt $0, 1f - - /* Return value is the unbiased priority, i.e. 20 - prio. - This does result in negative return values, so signal - no error by writing into the R0 slot. */ - lda $1, 20 - stq $31, 16($sp) - subl $1, $0, $0 - unop - -1: lda $sp, 16($sp) - ret -.end osf_getpriority - - .align 4 - .globl sys_getxuid - .ent sys_getxuid -sys_getxuid: - .prologue 0 - ldq $2, TI_TASK($8) - ldq $3, TASK_CRED($2) - ldl $0, CRED_UID($3) - ldl $1, CRED_EUID($3) - stq $1, 80($sp) - ret -.end sys_getxuid - - .align 4 - .globl sys_getxgid - .ent sys_getxgid -sys_getxgid: - .prologue 0 - ldq $2, TI_TASK($8) - ldq $3, TASK_CRED($2) - ldl $0, CRED_GID($3) - ldl $1, CRED_EGID($3) - stq $1, 80($sp) - ret -.end sys_getxgid - - .align 4 - .globl sys_getxpid - .ent sys_getxpid -sys_getxpid: - .prologue 0 - ldq $2, TI_TASK($8) - - /* See linux/kernel/timer.c sys_getppid for discussion - about this loop. */ - ldq $3, TASK_GROUP_LEADER($2) - ldq $4, TASK_REAL_PARENT($3) - ldl $0, TASK_TGID($2) -1: ldl $1, TASK_TGID($4) -#ifdef CONFIG_SMP - mov $4, $5 - mb - ldq $3, TASK_GROUP_LEADER($2) - ldq $4, TASK_REAL_PARENT($3) - cmpeq $4, $5, $5 - beq $5, 1b -#endif - stq $1, 80($sp) - ret -.end sys_getxpid - - .align 4 - .globl sys_alpha_pipe - .ent sys_alpha_pipe -sys_alpha_pipe: - lda $sp, -16($sp) - stq $26, 0($sp) - .prologue 0 - - mov $31, $17 - lda $16, 8($sp) - jsr $26, do_pipe_flags - - ldq $26, 0($sp) - bne $0, 1f - - /* The return values are in $0 and $20. */ - ldl $1, 12($sp) - ldl $0, 8($sp) - - stq $1, 80+16($sp) -1: lda $sp, 16($sp) - ret -.end sys_alpha_pipe - - .align 4 .globl sys_execve .ent sys_execve sys_execve: diff --git a/arch/alpha/kernel/osf_sys.c b/arch/alpha/kernel/osf_sys.c index 49ee319..3c4e16a 100644 --- a/arch/alpha/kernel/osf_sys.c +++ b/arch/alpha/kernel/osf_sys.c @@ -1238,3 +1238,52 @@ SYSCALL_DEFINE3(osf_writev, unsigned long, fd, } #endif + +SYSCALL_DEFINE2(osf_getpriority, int, which, int, who) +{ + int prio = sys_getpriority(which, who); + if (prio >= 0) { + /* Return value is the unbiased priority, i.e. 20 - prio. + This does result in negative return values, so signal + no error */ + force_successful_syscall_return(); + prio = 20 - prio; + } + return prio; +} + +SYSCALL_DEFINE0(getxuid) +{ + current_pt_regs()->r20 = sys_geteuid(); + return sys_getuid(); +} + +SYSCALL_DEFINE0(getxgid) +{ + current_pt_regs()->r20 = sys_getegid(); + return sys_getgid(); +} + +SYSCALL_DEFINE0(getxpid) +{ + current_pt_regs()->r20 = sys_getppid(); + return sys_getpid(); +} + +SYSCALL_DEFINE0(alpha_pipe) +{ + int fd[2]; + int res = do_pipe_flags(fd, 0); + if (!res) { + /* The return values are in $0 and $20. */ + current_pt_regs()->r20 = fd[1]; + res = fd[0]; + } + return res; +} + +SYSCALL_DEFINE1(sethae, unsigned long, val) +{ + current_pt_regs()->hae = val; + return 0; +} diff --git a/arch/alpha/kernel/systbls.S b/arch/alpha/kernel/systbls.S index e534e1c..97c9030 100644 --- a/arch/alpha/kernel/systbls.S +++ b/arch/alpha/kernel/systbls.S @@ -111,7 +111,7 @@ sys_call_table: .quad sys_socket .quad sys_connect .quad sys_accept - .quad osf_getpriority /* 100 */ + .quad sys_osf_getpriority /* 100 */ .quad sys_send .quad sys_recv .quad sys_sigreturn diff --git a/kernel/timer.c b/kernel/timer.c index 6ec7e7e..6885e5f 100644 --- a/kernel/timer.c +++ b/kernel/timer.c @@ -1394,13 +1394,6 @@ SYSCALL_DEFINE1(alarm, unsigned int, seconds) #endif -#ifndef __alpha__ - -/* - * The Alpha uses getxpid, getxuid, and getxgid instead. Maybe this - * should be moved into arch/i386 instead? - */ - /** * sys_getpid - return the thread group id of the current process * @@ -1456,8 +1449,6 @@ SYSCALL_DEFINE0(getegid) return from_kgid_munged(current_user_ns(), current_egid()); } -#endif - static void process_timeout(unsigned long __data) { wake_up_process((struct task_struct *)__data); -- To unsubscribe from this list: send the line "unsubscribe linux-alpha" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
