diff options
| author | Chris Metcalf <cmetcalf@tilera.com> | 2012-03-30 16:29:06 -0400 |
|---|---|---|
| committer | Chris Metcalf <cmetcalf@tilera.com> | 2012-04-02 12:14:03 -0400 |
| commit | e1d5c0195075abaa45cd04ca397dbeaa0d18c490 (patch) | |
| tree | 6ed1ccb2ab7cfda0dae569f3adbc667e7642dbe3 /arch/tile/kernel/intvec_64.S | |
| parent | b1760c847ff9d04fba7cdbef005a0ad805311c6d (diff) | |
| download | linux-e1d5c0195075abaa45cd04ca397dbeaa0d18c490.tar.gz | |
arch/tile: avoid accidentally unmasking NMI-type interrupt accidentally
The return path as we reload registers and core state requires that r30 hold a boolean indicating whether we are returning from an NMI, but in a couple of cases we weren't setting this properly, with the result that we could accidentally unmask the NMI interrupt(s), which could cause confusion. Now we set r30 in every place where we jump into the interrupt return path. Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
Diffstat (limited to 'arch/tile/kernel/intvec_64.S')
| -rw-r--r-- | arch/tile/kernel/intvec_64.S | 19 |
1 files changed, 16 insertions, 3 deletions
diff --git a/arch/tile/kernel/intvec_64.S b/arch/tile/kernel/intvec_64.S index fdff17c70cc8..49d9d6621682 100644 --- a/arch/tile/kernel/intvec_64.S +++ b/arch/tile/kernel/intvec_64.S @@ -606,6 +606,10 @@ handle_interrupt: * This routine takes a boolean in r30 indicating if this is an NMI. * If so, we also expect a boolean in r31 indicating whether to * re-enable the oprofile interrupts. + * + * Note that .Lresume_userspace is jumped to directly in several + * places, and we need to make sure r30 is set correctly in those + * callers as well. */ STD_ENTRY(interrupt_return) /* If we're resuming to kernel space, don't check thread flags. */ @@ -1058,7 +1062,10 @@ handle_syscall: } FEEDBACK_REENTER(handle_syscall) -2: j .Lresume_userspace /* jump into middle of interrupt_return */ +2: { + movei r30, 0 /* not an NMI */ + j .Lresume_userspace /* jump into middle of interrupt_return */ + } .Lcompat_syscall: /* @@ -1092,7 +1099,10 @@ handle_syscall: movei r28, -ENOSYS } st r29, r28 - j .Lresume_userspace /* jump into middle of interrupt_return */ + { + movei r30, 0 /* not an NMI */ + j .Lresume_userspace /* jump into middle of interrupt_return */ + } STD_ENDPROC(handle_syscall) /* Return the address for oprofile to suppress in backtraces. */ @@ -1108,7 +1118,10 @@ STD_ENTRY(ret_from_fork) jal sim_notify_fork jal schedule_tail FEEDBACK_REENTER(ret_from_fork) - j .Lresume_userspace + { + movei r30, 0 /* not an NMI */ + j .Lresume_userspace /* jump into middle of interrupt_return */ + } STD_ENDPROC(ret_from_fork) /* Various stub interrupt handlers and syscall handlers */ |