From: Roland McGrath Date: Wed, 30 Jan 2008 12:30:58 +0000 (+0100) Subject: x86: x86-32 ptrace get/putreg current task X-Git-Tag: v2.6.25-rc1~1143^2~671 X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=5fd4d16bd59a9fc84ca94c4fce4abc23fe219108;p=linux-2.6 x86: x86-32 ptrace get/putreg current task This generalizes the getreg and putreg functions so they can be used on the current task, as well as on a task stopped in TASK_TRACED and switched off. This lays the groundwork to share this code for all kinds of user-mode machine state access, not just ptrace. Signed-off-by: Roland McGrath Signed-off-by: Ingo Molnar Signed-off-by: Thomas Gleixner --- diff --git a/arch/x86/kernel/ptrace_32.c b/arch/x86/kernel/ptrace_32.c index 5aca84ef26..26071305de 100644 --- a/arch/x86/kernel/ptrace_32.c +++ b/arch/x86/kernel/ptrace_32.c @@ -55,6 +55,12 @@ static int putreg(struct task_struct *child, if (value && (value & 3) != 3) return -EIO; child->thread.gs = value; + if (child == current) + /* + * The user-mode %gs is not affected by + * kernel entry, so we must update the CPU. + */ + loadsegment(gs, value); return 0; case DS: case ES: @@ -104,6 +110,8 @@ static unsigned long getreg(struct task_struct *child, unsigned long regno) break; case GS: retval = child->thread.gs; + if (child == current) + savesegment(gs, retval); break; case DS: case ES: