[MIPS] Make prepare_frametrace() not clobber v0 (898d2291) · Commits · 戴 / test

Since lmo commit 323a380bf9e1a1679a774a2b053e3c1f2aa3f179 ("Simplify dump_stack()") made prepare_frametrace() always inlined, using $2 (v0) in __asm__ is not safe anymore. We can use $1 (at) instead. Also we should use "dla" instead of "la" for 64-bit kernel. Signed-off-by:

Atsushi Nemoto <anemo@mba.ocn.ne.jp> Signed-off-by:

Ralf Baechle <ralf@linux-mips.org>

arch/mips/kernel/traps.c

+7 −3

Original line number	Diff line number	Diff line
		@@ -161,16 +161,20 @@ static void show_stacktrace(struct task_struct task, struct pt_regs regs)
		static __always_inline void prepare_frametrace(struct pt_regs *regs)
		{
		__asm__ __volatile__(
		"1: la $2, 1b\n\t"
		".set push\n\t"
		".set noat\n\t"
		#ifdef CONFIG_64BIT
		"sd $2, %0\n\t"
		"1: dla $1, 1b\n\t"
		"sd $1, %0\n\t"
		"sd $29, %1\n\t"
		"sd $31, %2\n\t"
		#else
		"sw $2, %0\n\t"
		"1: la $1, 1b\n\t"
		"sw $1, %0\n\t"
		"sw $29, %1\n\t"
		"sw $31, %2\n\t"
		#endif
		".set pop\n\t"
		: "=m" (regs->cp0_epc),
		"=m" (regs->regs[29]), "=m" (regs->regs[31])
		: : "memory");

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