diff options
author | David S. Miller <davem@davemloft.net> | 2010-02-19 18:19:52 -0500 |
---|---|---|
committer | David S. Miller <davem@davemloft.net> | 2010-02-19 18:19:52 -0500 |
commit | 1f474646fdc36b457606bbcd6a3592e6cbd31ac4 (patch) | |
tree | 706149d39c9de0bc0ceacfb2ab44e909caba5b3c /arch | |
parent | d7ecfb3c2aa155c9f6152ebe91de92067d16ba6e (diff) |
sparc64: Fix sun4u execute bit check in TSB I-TLB load.
Thanks to testcase and report from Brad Spengler:
--------------------
#include <stdio.h>
typedef int (* _wee)(void);
int main(void)
{
char buf[8] = { '\x81', '\xc7', '\xe0', '\x08', '\x81', '\xe8',
'\x00', '\x00' };
_wee wee;
printf("%p\n", &buf);
wee = (_wee)&buf;
wee();
return 0;
}
--------------------
TSB I-tlb load code tries to use andcc to check the _PAGE_EXEC_4U bit,
but that's bit 12 so it gets sign extended all the way up to bit 63
and the test nearly always passes as a result.
Use sethi to fix the bug.
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'arch')
-rw-r--r-- | arch/sparc/kernel/tsb.S | 6 |
1 files changed, 4 insertions, 2 deletions
diff --git a/arch/sparc/kernel/tsb.S b/arch/sparc/kernel/tsb.S index 8c91d9b29a2f..db15d123f054 100644 --- a/arch/sparc/kernel/tsb.S +++ b/arch/sparc/kernel/tsb.S | |||
@@ -191,10 +191,12 @@ tsb_dtlb_load: | |||
191 | 191 | ||
192 | tsb_itlb_load: | 192 | tsb_itlb_load: |
193 | /* Executable bit must be set. */ | 193 | /* Executable bit must be set. */ |
194 | 661: andcc %g5, _PAGE_EXEC_4U, %g0 | 194 | 661: sethi %hi(_PAGE_EXEC_4U), %g4 |
195 | .section .sun4v_1insn_patch, "ax" | 195 | andcc %g5, %g4, %g0 |
196 | .section .sun4v_2insn_patch, "ax" | ||
196 | .word 661b | 197 | .word 661b |
197 | andcc %g5, _PAGE_EXEC_4V, %g0 | 198 | andcc %g5, _PAGE_EXEC_4V, %g0 |
199 | nop | ||
198 | .previous | 200 | .previous |
199 | 201 | ||
200 | be,pn %xcc, tsb_do_fault | 202 | be,pn %xcc, tsb_do_fault |