From 52ab532ea76d30b7e7a7b98021e2e873e83029a5 Mon Sep 17 00:00:00 2001 From: Al Viro Date: Sun, 9 Dec 2012 06:16:14 +0000 Subject: parisc: fix ptrace breakage 1) PTRACE_SYSCALL doesn't work for 64bit process on parisc64. Compat syscall table is used instead of 64bit one. IMO we should either refuse to allow PTRACE_SYSCALL for 64bit processes or duplicate the logics choosing the right syscall table into .Ltracesys. 2) if you have let the tracee run with PTRACE_SYSCALL and it had stopped, you can use PTRACE_POKEUSR to modify syscall number (r20) and arguments 1--4 (r26--r23). Modifications will have effect. However, modifying arguments 5 and 6 (r22 and r21 resp.) works only when process (32bit one) runs on 64bit host - on 32bit one it has no effect. AFAICS, the diff below should fix that one. Signed-off-by: Al Viro Tested-by: John David Anglin Signed-off-by: Helge Deller --- arch/parisc/kernel/syscall.S | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) (limited to 'arch/parisc/kernel') diff --git a/arch/parisc/kernel/syscall.S b/arch/parisc/kernel/syscall.S index 86742df0b194..5e055240f00b 100644 --- a/arch/parisc/kernel/syscall.S +++ b/arch/parisc/kernel/syscall.S @@ -309,10 +309,13 @@ tracesys_next: LDREG TASK_PT_GR25(%r1), %r25 LDREG TASK_PT_GR24(%r1), %r24 LDREG TASK_PT_GR23(%r1), %r23 -#ifdef CONFIG_64BIT LDREG TASK_PT_GR22(%r1), %r22 LDREG TASK_PT_GR21(%r1), %r21 +#ifdef CONFIG_64BIT ldo -16(%r30),%r29 /* Reference param save area */ +#else + stw %r22, -52(%r30) /* 5th argument */ + stw %r21, -56(%r30) /* 6th argument */ #endif comiclr,>>= __NR_Linux_syscalls, %r20, %r0 -- cgit v1.2.3