From 4338774cd41a6abf72aa76585ce2184cea8ff8a2 Mon Sep 17 00:00:00 2001 From: Dave Jones Date: Tue, 18 Jun 2013 12:09:11 -0400 Subject: x86/debug: Only print out DR registers if they are not power-on defaults The DR registers are rarely useful when decoding oopses. With screen real estate during oopses at a premium, we can save two lines by only printing out these registers when they are set to something other than they power-on state. Signed-off-by: Dave Jones Acked-by: Borislav Petkov Cc: Linus Torvalds Cc: Andrew Morton Cc: Peter Zijlstra Cc: Thomas Gleixner Link: http://lkml.kernel.org/r/20130618160911.GA24487@redhat.com Signed-off-by: Ingo Molnar --- arch/x86/kernel/process_32.c | 11 ++++++++--- 1 file changed, 8 insertions(+), 3 deletions(-) (limited to 'arch/x86/kernel/process_32.c') diff --git a/arch/x86/kernel/process_32.c b/arch/x86/kernel/process_32.c index 7305f7dfc7a..f84cfd1b0c0 100644 --- a/arch/x86/kernel/process_32.c +++ b/arch/x86/kernel/process_32.c @@ -110,11 +110,16 @@ void __show_regs(struct pt_regs *regs, int all) get_debugreg(d1, 1); get_debugreg(d2, 2); get_debugreg(d3, 3); - printk(KERN_DEFAULT "DR0: %08lx DR1: %08lx DR2: %08lx DR3: %08lx\n", - d0, d1, d2, d3); - get_debugreg(d6, 6); get_debugreg(d7, 7); + + /* Only print out debug registers if they are in their non-default state. */ + if ((d0 == 0) && (d1 == 0) && (d2 == 0) && (d3 == 0) && + (d6 == DR6_RESERVED) && (d7 == 0x400)) + return; + + printk(KERN_DEFAULT "DR0: %08lx DR1: %08lx DR2: %08lx DR3: %08lx\n", + d0, d1, d2, d3); printk(KERN_DEFAULT "DR6: %08lx DR7: %08lx\n", d6, d7); } -- cgit v1.2.3