diff options
author | Jason Wessel <jason.wessel@windriver.com> | 2009-12-11 08:43:16 -0600 |
---|---|---|
committer | Jason Wessel <jason.wessel@windriver.com> | 2009-12-11 08:43:16 -0600 |
commit | cf6f196d112a6f6757b1ca3cce0b576f7abee479 (patch) | |
tree | 977a9e18167112af168ce49f95b5d26fe1bec46d /arch/x86/kernel/kgdb.c | |
parent | 59d309f9c8ef0bd01bf93cc0e758f1d810417bdb (diff) | |
download | blackbird-op-linux-cf6f196d112a6f6757b1ca3cce0b576f7abee479.tar.gz blackbird-op-linux-cf6f196d112a6f6757b1ca3cce0b576f7abee479.zip |
kgdb,i386: Fix corner case access to ss with NMI watch dog exception
It is possible for the user_mode_vm(regs) check to return true on the
i368 arch for a non master kgdb cpu or when the master kgdb cpu
handles the NMI watch dog exception.
The solution is simply to select the correct gdb_ss location
based on the check to user_mode_vm(regs).
CC: Ingo Molnar <mingo@elte.hu>
Acked-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
Diffstat (limited to 'arch/x86/kernel/kgdb.c')
-rw-r--r-- | arch/x86/kernel/kgdb.c | 10 |
1 files changed, 8 insertions, 2 deletions
diff --git a/arch/x86/kernel/kgdb.c b/arch/x86/kernel/kgdb.c index f93d015753ce..aefae46aa646 100644 --- a/arch/x86/kernel/kgdb.c +++ b/arch/x86/kernel/kgdb.c @@ -86,9 +86,15 @@ void pt_regs_to_gdb_regs(unsigned long *gdb_regs, struct pt_regs *regs) gdb_regs[GDB_DS] = regs->ds; gdb_regs[GDB_ES] = regs->es; gdb_regs[GDB_CS] = regs->cs; - gdb_regs[GDB_SS] = __KERNEL_DS; gdb_regs[GDB_FS] = 0xFFFF; gdb_regs[GDB_GS] = 0xFFFF; + if (user_mode_vm(regs)) { + gdb_regs[GDB_SS] = regs->ss; + gdb_regs[GDB_SP] = regs->sp; + } else { + gdb_regs[GDB_SS] = __KERNEL_DS; + gdb_regs[GDB_SP] = kernel_stack_pointer(regs); + } #else gdb_regs[GDB_R8] = regs->r8; gdb_regs[GDB_R9] = regs->r9; @@ -101,8 +107,8 @@ void pt_regs_to_gdb_regs(unsigned long *gdb_regs, struct pt_regs *regs) gdb_regs32[GDB_PS] = regs->flags; gdb_regs32[GDB_CS] = regs->cs; gdb_regs32[GDB_SS] = regs->ss; -#endif gdb_regs[GDB_SP] = kernel_stack_pointer(regs); +#endif } /** |