sched/x86/64, kgdb: Clear GDB_PS on 64-bit

switch_to() no longer saves EFLAGS, so it's bogus to look for it on the
stack.  Set it to zero like 32-bit.

Signed-off-by: Brian Gerst <brgerst@gmail.com>
Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Jason Wessel <jason.wessel@windriver.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1471106302-10159-3-git-send-email-brgerst@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>

diff --git a/arch/x86/kernel/kgdb.c b/arch/x86/kernel/kgdb.c
index fe649a5..5e3f294 100644 (file)
--- a/arch/x86/kernel/kgdb.c
+++ b/arch/x86/kernel/kgdb.c
@@ -176,7 +176,7 @@ void sleeping_thread_to_gdb_regs(unsigned long *gdb_regs, struct task_struct *p)
        gdb_regs[GDB_FS]        = 0xFFFF;
        gdb_regs[GDB_GS]        = 0xFFFF;
 #else
-       gdb_regs32[GDB_PS]      = *(unsigned long *)(p->thread.sp + 8);
+       gdb_regs32[GDB_PS]      = 0;
        gdb_regs32[GDB_CS]      = __KERNEL_CS;
        gdb_regs32[GDB_SS]      = __KERNEL_DS;
        gdb_regs[GDB_R8]        = 0;