[patch] 2.4.0-test2: %cr4 in a register dump

• Next message: Tigran Aivazian: "foo vs task_struct and kernel timers?"
• Previous message: Andi Kleen: "PS/2 mouse latency was Re: [linux-audio-dev] Re: [DATAPOINT] kernels and latencies"
• Next in thread: Tigran Aivazian: "Re: [patch] 2.4.0-test2: %cr4 in a register dump"
• Reply: Tigran Aivazian: "Re: [patch] 2.4.0-test2: %cr4 in a register dump"
• Reply: Maciej W. Rozycki: "[patch] 2.4.0-test2: %cr4 in a register dump (a cosmetic update)"
• Maybe reply: Linus Torvalds: "Re: [patch] 2.4.0-test2: %cr4 in a register dump"
• Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]

Hi,

 It looks like Linux makes more and more use of the %cr4 register. But it
is not included in a register dump. I use the following patch to include
the register in the dump. The code tries to approximate the %cr4 presence
condition by cpuid flags and is hopefully obvious. It applies cleanly to
2.4.0-test2. So far I used it to verify the "notsc" option works as
expected.

  Maciej

-- 
+  Maciej W. Rozycki, Technical University of Gdansk, Poland   +
+--------------------------------------------------------------+
+        e-mail: macro@ds2.pg.gda.pl, PGP key available        +
diff -u --recursive --new-file linux-2.4-test1.macro/arch/i386/kernel/process.c linux-2.4-test1/arch/i386/kernel/process.c
--- linux-2.4-test1.macro/arch/i386/kernel/process.c	Fri May 26 22:24:15 2000
+++ linux-2.4-test1/arch/i386/kernel/process.c	Tue May 30 00:54:34 2000
@@ -342,7 +342,7 @@
 
 void show_regs(struct pt_regs * regs)
 {
-	long cr0 = 0L, cr2 = 0L, cr3 = 0L;
+	long cr0 = 0L, cr2 = 0L, cr3 = 0L, cr4 = 0L;
 
 	printk("\n");
 	printk("EIP: %04x:[<%08lx>]",0xffff & regs->xcs,regs->eip);
@@ -359,7 +359,15 @@
 	__asm__("movl %%cr0, %0": "=r" (cr0));
 	__asm__("movl %%cr2, %0": "=r" (cr2));
 	__asm__("movl %%cr3, %0": "=r" (cr3));
-	printk("CR0: %08lx CR2: %08lx CR3: %08lx\n", cr0, cr2, cr3);
+	printk("CR0: %08lx CR2: %08lx CR3: %08lx", cr0, cr2, cr3);
+	if (current_cpu_data.x86_capability &
+	    (X86_FEATURE_VME | X86_FEATURE_DE | X86_FEATURE_PSE |
+	     X86_FEATURE_TSC | X86_FEATURE_PAE | X86_FEATURE_MCE |
+	     X86_FEATURE_PGE | X86_FEATURE_FXSR | X86_FEATURE_XMM)) {
+		__asm__("movl %%cr4, %0": "=r" (cr4));
+		printk(" CR4: %08lx\n", cr4);
+	}
+	printk("\n");
 }
 
 /*
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.rutgers.edu
Please read the FAQ at http://www.tux.org/lkml/

• Next message: Tigran Aivazian: "foo vs task_struct and kernel timers?"
• Previous message: Andi Kleen: "PS/2 mouse latency was Re: [linux-audio-dev] Re: [DATAPOINT] kernels and latencies"
• Next in thread: Tigran Aivazian: "Re: [patch] 2.4.0-test2: %cr4 in a register dump"
• Reply: Tigran Aivazian: "Re: [patch] 2.4.0-test2: %cr4 in a register dump"
• Reply: Maciej W. Rozycki: "[patch] 2.4.0-test2: %cr4 in a register dump (a cosmetic update)"
• Maybe reply: Linus Torvalds: "Re: [patch] 2.4.0-test2: %cr4 in a register dump"
• Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]

This archive was generated by hypermail 2b29 : Fri Jul 07 2000 - 21:00:15 EST