diff options
| author | Helge Deller <deller@gmx.de> | 2016-04-08 18:32:52 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2016-04-20 15:45:05 +0900 |
| commit | 23e52d58f376cfed2d4d5b8b4789d3bf7ce5360a (patch) | |
| tree | 254c0869fc073bc873483675624e80f0195c0919 /arch/parisc/lib | |
| parent | 1abe5c5fa89d2730a6f4d4b1aaa3f847e5adeaa7 (diff) | |
| download | lwn-23e52d58f376cfed2d4d5b8b4789d3bf7ce5360a.tar.gz lwn-23e52d58f376cfed2d4d5b8b4789d3bf7ce5360a.zip | |
parisc: Unbreak handling exceptions from kernel modules
commit 2ef4dfd9d9f288943e249b78365a69e3ea3ec072 upstream.
Handling exceptions from modules never worked on parisc.
It was just masked by the fact that exceptions from modules
don't happen during normal use.
When a module triggers an exception in get_user() we need to load the
main kernel dp value before accessing the exception_data structure, and
afterwards restore the original dp value of the module on exit.
Noticed-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'arch/parisc/lib')
| -rw-r--r-- | arch/parisc/lib/fixup.S | 6 |
1 files changed, 6 insertions, 0 deletions
diff --git a/arch/parisc/lib/fixup.S b/arch/parisc/lib/fixup.S index 536ef66bb94b..1052b747e011 100644 --- a/arch/parisc/lib/fixup.S +++ b/arch/parisc/lib/fixup.S @@ -26,6 +26,7 @@ #ifdef CONFIG_SMP .macro get_fault_ip t1 t2 + loadgp addil LT%__per_cpu_offset,%r27 LDREG RT%__per_cpu_offset(%r1),\t1 /* t2 = smp_processor_id() */ @@ -40,14 +41,19 @@ LDREG RT%exception_data(%r1),\t1 /* t1 = this_cpu_ptr(&exception_data) */ add,l \t1,\t2,\t1 + /* %r27 = t1->fault_gp - restore gp */ + LDREG EXCDATA_GP(\t1), %r27 /* t1 = t1->fault_ip */ LDREG EXCDATA_IP(\t1), \t1 .endm #else .macro get_fault_ip t1 t2 + loadgp /* t1 = this_cpu_ptr(&exception_data) */ addil LT%exception_data,%r27 LDREG RT%exception_data(%r1),\t2 + /* %r27 = t2->fault_gp - restore gp */ + LDREG EXCDATA_GP(\t2), %r27 /* t1 = t2->fault_ip */ LDREG EXCDATA_IP(\t2), \t1 .endm |