Messages in this thread Patch in this message | | | Date | Tue, 1 Jul 2008 08:19:16 -0700 | From | Greg KH <> | Subject | [patch 7/9] ptrace GET/SET FPXREGS broken |
| |
2.6.25-stable review patch. If anyone has any objections, please let us know.
------------------
From: TAKADA Yoshihito <takada@mbf.nifty.com>
Commit 11dbc963a8f6128595d0f6ecf138dc369e144997 upstream
ptrace GET/SET FPXREGS broken
When I update kernel 2.6.25 from 2.6.24, gdb does not work. On 2.6.25, ptrace(PTRACE_GETFPXREGS, ...) returns ENODEV.
But 2.6.24 kernel's ptrace() returns EIO. It is issue of compatibility.
I attached test program as pt.c and patch for fix it.
#include <stdio.h> #include <stdlib.h> #include <unistd.h> #include <signal.h> #include <errno.h> #include <sys/ptrace.h> #include <sys/types.h>
struct user_fxsr_struct { unsigned short cwd; unsigned short swd; unsigned short twd; unsigned short fop; long fip; long fcs; long foo; long fos; long mxcsr; long reserved; long st_space[32]; /* 8*16 bytes for each FP-reg = 128 bytes */ long xmm_space[32]; /* 8*16 bytes for each XMM-reg = 128 bytes */ long padding[56]; };
int main(void) { pid_t pid;
pid = fork();
switch(pid){ case -1:/* error */ break; case 0:/* child */ child(); break; default: parent(pid); break; } return 0; }
int child(void) { ptrace(PTRACE_TRACEME); kill(getpid(), SIGSTOP); sleep(10); return 0; } int parent(pid_t pid) { int ret; struct user_fxsr_struct fpxregs;
ret = ptrace(PTRACE_GETFPXREGS, pid, 0, &fpxregs); if(ret < 0){ printf("%d: %s.\n", errno, strerror(errno)); } kill(pid, SIGCONT); wait(pid); return 0; }
/* in the kerel, at kernel/i387.c get_fpxregs() */
Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
--- arch/x86/kernel/i387.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)
--- a/arch/x86/kernel/i387.c +++ b/arch/x86/kernel/i387.c @@ -130,7 +130,7 @@ int xfpregs_get(struct task_struct *targ void *kbuf, void __user *ubuf) { if (!cpu_has_fxsr) - return -ENODEV; + return -EIO; init_fpu(target); @@ -145,7 +145,7 @@ int xfpregs_set(struct task_struct *targ int ret; if (!cpu_has_fxsr) - return -ENODEV; + return -EIO; init_fpu(target); set_stopped_child_used_math(target); --
| |