| Message ID | 20130917215749.GA11109@obsidianresearch.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Tue, Sep 17, 2013 at 10:57:49PM +0100, Jason Gunthorpe wrote: > Hi Will, Hi Jason, > I was just testing v3.12-rc1 (on kirkwood) and noticed that strace is > not working: Thanks for the report! > $ strace /bin/ls > mmap2(0xb6f79000, 9552, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0) = 0xb6f79000 > close(3) = 0 > mmap2(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0xb6fad000 > set_tls(0xb6fad4c0, 0xb6fadb98, 0xb6fb1050, 0xb6fad4c0, 0xb6fb1050) = -1 ENOSYS (Function not implemented) > writev(2, [{"cannot set up thread-local stora"..., 36}, {"unknown error", 13}, {"\n", 1}], 3cannot set up thread-local storage: unknown error > ) = 50 > exit_group(127) = ? > +++ exited with 127 +++ > > I determined that reverting your commit below makes strace work again. > I've tested 3.10.12 and it is OK. Hmm, so if you don't run with strace, does `/bin/ls' work as expected? From the trace above, it seems that set_tls is failing rather than anything in strace (unless of course, the trace is just plain wrong). > This happens with the latest git head for strace, as well as the 4.7 > release. > > Hopefully you can cook up a fix :) I'll take a look today, thanks. Will
diff --git a/arch/arm/kernel/entry-common.S b/arch/arm/kernel/entry-common.S index 94104bf..74ad15d1 100644 --- a/arch/arm/kernel/entry-common.S +++ b/arch/arm/kernel/entry-common.S @@ -442,10 +442,10 @@ local_restart: ldrcc pc, [tbl, scno, lsl #2] @ call sys_* routine add r1, sp, #S_OFF -2: mov why, #0 @ no longer a real syscall cmp scno, #(__ARM_NR_BASE - __NR_SYSCALL_BASE) eor r0, scno, #__NR_SYSCALL_BASE @ put OS number back - bcs arm_syscall + bcs arm_syscall +2: mov why, #0 @ no longer a real syscall b sys_ni_syscall @ not private func #if defined(CONFIG_OABI_COMPAT) || !defined(CONFIG_AEABI)
Hi Will, I was just testing v3.12-rc1 (on kirkwood) and noticed that strace is not working: $ strace /bin/ls mmap2(0xb6f79000, 9552, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0) = 0xb6f79000 close(3) = 0 mmap2(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0xb6fad000 set_tls(0xb6fad4c0, 0xb6fadb98, 0xb6fb1050, 0xb6fad4c0, 0xb6fb1050) = -1 ENOSYS (Function not implemented) writev(2, [{"cannot set up thread-local stora"..., 36}, {"unknown error", 13}, {"\n", 1}], 3cannot set up thread-local storage: unknown error ) = 50 exit_group(127) = ? +++ exited with 127 +++ I determined that reverting your commit below makes strace work again. I've tested 3.10.12 and it is OK. This happens with the latest git head for strace, as well as the 4.7 release. Hopefully you can cook up a fix :) Regards, Jason commit 377747c40657eb35ad98a56439606d96a928425a Author: Will Deacon <will.deacon@arm.com> Date: Mon May 13 19:16:34 2013 +0100 ARM: entry: allow ARM-private syscalls to be restarted System calls will only be restarted after signal handling if they (a) return an error code indicating that a restart is required and (b) have `why' set to a non-zero value, to indicate that the signal interrupted them. This patch leaves `why' set to a non-zero value for ARM-private syscalls , and only zeroes it for syscalls that are not implemented. Signed-off-by: Will Deacon <will.deacon@arm.com>