diff options
| author | Peter Zijlstra <peterz@infradead.org> | 2019-05-07 23:25:54 +0200 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2019-06-25 10:23:47 +0200 |
| commit | 3c88c692c28746473791276f8b42d2c989d6cbe6 (patch) | |
| tree | 51cb03ef4cbb611f42ea43c8737be894991b656b /arch/x86/kernel/process_32.c | |
| parent | ea1ed38dba64b64a245ab8ca1406269d17b99485 (diff) | |
x86/stackframe/32: Provide consistent pt_regs
Currently pt_regs on x86_32 has an oddity in that kernel regs
(!user_mode(regs)) are short two entries (esp/ss). This means that any
code trying to use them (typically: regs->sp) needs to jump through
some unfortunate hoops.
Change the entry code to fix this up and create a full pt_regs frame.
This then simplifies various trampolines in ftrace and kprobes, the
stack unwinder, ptrace, kdump and kgdb.
Much thanks to Josh for help with the cleanups!
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'arch/x86/kernel/process_32.c')
| -rw-r--r-- | arch/x86/kernel/process_32.c | 16 |
1 files changed, 5 insertions, 11 deletions
diff --git a/arch/x86/kernel/process_32.c b/arch/x86/kernel/process_32.c index 2399e910d109..b8ceec4974fe 100644 --- a/arch/x86/kernel/process_32.c +++ b/arch/x86/kernel/process_32.c @@ -62,27 +62,21 @@ void __show_regs(struct pt_regs *regs, enum show_regs_mode mode) { unsigned long cr0 = 0L, cr2 = 0L, cr3 = 0L, cr4 = 0L; unsigned long d0, d1, d2, d3, d6, d7; - unsigned long sp; - unsigned short ss, gs; + unsigned short gs; - if (user_mode(regs)) { - sp = regs->sp; - ss = regs->ss; + if (user_mode(regs)) gs = get_user_gs(regs); - } else { - sp = kernel_stack_pointer(regs); - savesegment(ss, ss); + else savesegment(gs, gs); - } show_ip(regs, KERN_DEFAULT); printk(KERN_DEFAULT "EAX: %08lx EBX: %08lx ECX: %08lx EDX: %08lx\n", regs->ax, regs->bx, regs->cx, regs->dx); printk(KERN_DEFAULT "ESI: %08lx EDI: %08lx EBP: %08lx ESP: %08lx\n", - regs->si, regs->di, regs->bp, sp); + regs->si, regs->di, regs->bp, regs->sp); printk(KERN_DEFAULT "DS: %04x ES: %04x FS: %04x GS: %04x SS: %04x EFLAGS: %08lx\n", - (u16)regs->ds, (u16)regs->es, (u16)regs->fs, gs, ss, regs->flags); + (u16)regs->ds, (u16)regs->es, (u16)regs->fs, gs, regs->ss, regs->flags); if (mode != SHOW_REGS_ALL) return; |