From 15029285dc977a392e74eacb7625984b71d4f605 Mon Sep 17 00:00:00 2001 From: Jason Uhlenkott Date: Fri, 30 Dec 2005 02:27:01 -0800 Subject: [IA64] Handle debug traps in fsys mode We need to handle debug traps in fsys mode non-fatally. They can happen now that we have fsyscalls which contain probe instructions. Signed-off-by: Jason Uhlenkott Signed-off-by: Tony Luck --- arch/ia64/kernel/traps.c | 26 +++++++++++++++++++------- 1 file changed, 19 insertions(+), 7 deletions(-) (limited to 'arch/ia64/kernel/traps.c') diff --git a/arch/ia64/kernel/traps.c b/arch/ia64/kernel/traps.c index d3e0ecb56d62..55391901b013 100644 --- a/arch/ia64/kernel/traps.c +++ b/arch/ia64/kernel/traps.c @@ -530,12 +530,15 @@ ia64_fault (unsigned long vector, unsigned long isr, unsigned long ifa, if (fsys_mode(current, ®s)) { extern char __kernel_syscall_via_break[]; /* - * Got a trap in fsys-mode: Taken Branch Trap and Single Step trap - * need special handling; Debug trap is not supposed to happen. + * Got a trap in fsys-mode: Taken Branch Trap + * and Single Step trap need special handling; + * Debug trap is ignored (we disable it here + * and re-enable it in the lower-privilege trap). */ if (unlikely(vector == 29)) { - die("Got debug trap in fsys-mode---not supposed to happen!", - ®s, 0); + set_thread_flag(TIF_DB_DISABLED); + ia64_psr(®s)->db = 0; + ia64_psr(®s)->lp = 1; return; } /* re-do the system call via break 0x100000: */ @@ -589,10 +592,19 @@ ia64_fault (unsigned long vector, unsigned long isr, unsigned long ifa, case 34: if (isr & 0x2) { /* Lower-Privilege Transfer Trap */ + + /* If we disabled debug traps during an fsyscall, + * re-enable them here. + */ + if (test_thread_flag(TIF_DB_DISABLED)) { + clear_thread_flag(TIF_DB_DISABLED); + ia64_psr(®s)->db = 1; + } + /* - * Just clear PSR.lp and then return immediately: all the - * interesting work (e.g., signal delivery is done in the kernel - * exit path). + * Just clear PSR.lp and then return immediately: + * all the interesting work (e.g., signal delivery) + * is done in the kernel exit path. */ ia64_psr(®s)->lp = 0; return; -- cgit