leandrof/linux
1
0
Fork 0
forked from Minki/linux
Code Issues Pull Requests Packages Projects Releases Wiki Activity

tile: improve illegal translation interrupt handling

Browse Source 
First, don't re-enable interrupts blindly in the Linux trap handler.
We already handle page faults this way; synchronous interrupts like
ILL_TRANS will fire even when interrupts are disabled, and we don't
want to re-enable interrupts in that case.

For ILL_TRANS, we now pass the ILL_VA_PC reason into the trap handler
so we can report it properly; this is the address that caused the
illegal translation trap.  We print the address as part of the
pr_alert() message now if it's coming from the kernel.

Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
This commit is contained in:
Chris Metcalf 2013-08-07 12:11:56 -04:00
parent dadf78bf03
commit 70d2b5958a
2 changed files with 16 additions and 11 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
arch/tile/kernel/intvec_64.S
View File

@ -492,7 +492,7 @@ intvec_\vecname:
mfspr r3, SPR_SYSTEM_SAVE_K_2 /* info about page fault */
.else
.ifc \vecnum, INT_ILL_TRANS
mfspr r2, ILL_TRANS_REASON
mfspr r2, ILL_VA_PC
.else
.ifc \vecnum, INT_DOUBLE_FAULT
mfspr r2, SPR_SYSTEM_SAVE_K_2 /* double fault info from HV */

25
arch/tile/kernel/traps.c
View File

@ -222,8 +222,9 @@ void __kprobes do_trap(struct pt_regs *regs, int fault_num,
unsigned long address = 0;
bundle_bits instr;
/* Re-enable interrupts. */
local_irq_enable();
/* Re-enable interrupts, if they were previously enabled. */
if (!(regs->flags & PT_FLAGS_DISABLE_IRQ))
local_irq_enable();
/*
* If it hits in kernel mode and we can't fix it up, just exit the
@ -231,7 +232,8 @@ void __kprobes do_trap(struct pt_regs *regs, int fault_num,
*/
if (!user_mode(regs)) {
const char *name;
if (fixup_exception(regs)) /* only UNALIGN_DATA in practice */
char buf[100];
if (fixup_exception(regs)) /* ILL_TRANS or UNALIGN_DATA */
return;
if (fault_num >= 0 &&
fault_num < sizeof(int_name)/sizeof(int_name[0]) &&
@ -239,10 +241,16 @@ void __kprobes do_trap(struct pt_regs *regs, int fault_num,
name = int_name[fault_num];
else
name = "Unknown interrupt";
pr_alert("Kernel took bad trap %d (%s) at PC %#lx\n",
fault_num, name, regs->pc);
if (fault_num == INT_GPV)
pr_alert("GPV_REASON is %#lx\n", reason);
snprintf(buf, sizeof(buf), "; GPV_REASON %#lx", reason);
#ifdef __tilegx__
else if (fault_num == INT_ILL_TRANS)
snprintf(buf, sizeof(buf), "; address %#lx", reason);
#endif
else
buf[0] = '\0';
pr_alert("Kernel took bad trap %d (%s) at PC %#lx%s\n",
fault_num, name, regs->pc, buf);
show_regs(regs);
do_exit(SIGKILL); /* FIXME: implement i386 die() */
return;
@ -324,11 +332,8 @@ void __kprobes do_trap(struct pt_regs *regs, int fault_num,
fill_ra_stack();
signo = SIGSEGV;
address = reason;
code = SEGV_MAPERR;
if (reason & SPR_ILL_TRANS_REASON__I_STREAM_VA_RMASK)
address = regs->pc;
else
address = 0; /* FIXME: GX: single-step for address */
break;
}
#endif