FAQ Search Today's Posts Mark Forums Read
» Video Reviews

» Linux Archive

Linux-archive is a website aiming to archive linux email lists and to make them easily accessible for linux users/developers.


» Sponsor

» Partners

» Sponsor

Go Back   Linux Archive > Ubuntu > Ubuntu Kernel Team

 
 
LinkBack Thread Tools
 
Old 03-06-2008, 09:47 PM
David S. Miller
 
Default SPARC64: Loosen checks in exception table handling.

Bug: #301608

Upstream commits: 622eaec613130e6ea78f2a5d5070e3278b21cd8f
be71716e464f4ea38f08034dc666f2feb55535d9

Some parts of the kernel now do things like do *_user() accesses while
set_fs(KERNEL_DS) that fault on purpose.

See, for example, the code added by changeset
a0c1e9073ef7428a14309cba010633a6cd6719ea ("futex: runtime enable pi
and robust functionality").

That trips up the ASI sanity checking we make in do_kernel_fault().

Just remove it for now. Maybe we can add it back later with an added
conditional which looks at the current get_fs() value.

Also, because of the new futex validation init handler, we have
to accept faults in init section text as well as the normal
kernel text.

Thanks to Tom Callaway for the bug report.

Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Chris Wright <chrisw@sous-sol.org>
Signed-off-by: Stefan Bader <stefan.bader@canonical.com>
---
arch/sparc64/mm/fault.c | 14 +++-----------
1 files changed, 3 insertions(+), 11 deletions(-)

diff --git a/arch/sparc64/mm/fault.c b/arch/sparc64/mm/fault.c
index e2027f2..2650d0d 100644
--- a/arch/sparc64/mm/fault.c
+++ b/arch/sparc64/mm/fault.c
@@ -244,16 +244,8 @@ static void do_kernel_fault(struct pt_regs *regs, int si_code, int fault_code,
if (regs->tstate & TSTATE_PRIV) {
const struct exception_table_entry *entry;

- if (asi == ASI_P && (insn & 0xc0800000) == 0xc0800000) {
- if (insn & 0x2000)
- asi = (regs->tstate >> 24);
- else
- asi = (insn >> 5);
- }
-
- /* Look in asi.h: All _S asis have LS bit set */
- if ((asi & 0x1) &&
- (entry = search_exception_tables(regs->tpc))) {
+ entry = search_exception_tables(regs->tpc);
+ if (entry) {
regs->tpc = entry->fixup;
regs->tnpc = regs->tpc + 4;
return;
@@ -294,7 +286,7 @@ asmlinkage void __kprobes do_sparc64_fault(struct pt_regs *regs)
unsigned long tpc = regs->tpc;

/* Sanity check the PC. */
- if ((tpc >= KERNBASE && tpc < (unsigned long) _etext) ||
+ if ((tpc >= KERNBASE && tpc < (unsigned long) __init_end) ||
(tpc >= MODULES_VADDR && tpc < MODULES_END)) {
/* Valid, no problems... */
} else {
--
1.5.4.3


--------------020605060804020706030600
Content-Type: text/x-diff;
name="0002-SPARC-Fix-link-errors-with-gcc-4.3.patch"
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
filename="0002-SPARC-Fix-link-errors-with-gcc-4.3.patch"
 

Thread Tools




All times are GMT. The time now is 02:59 PM.

VBulletin, Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
Content Relevant URLs by vBSEO ©2007, Crawlability, Inc.
Copyright 2007 - 2008, www.linux-archive.org