[08/13] x86: do not use print_symbol()

Message ID 20171211125025.2270-9-sergey.senozhatsky@gmail.com
State New
Headers show
Series
  • replace print_symbol() with printk()-s
Related show

Commit Message

Sergey Senozhatsky Dec. 11, 2017, 12:50 p.m.
print_symbol() uses extra stack space to sprintf() symbol
information and then to feed that buffer to printk()

  char buffer[KSYM_SYMBOL_LEN];

  sprint_symbol(buffer, address);
  printk(fmt, buffer);

Replace print_symbol() with a direct printk("%pS") call.

Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
---
 arch/x86/kernel/cpu/mcheck/mce.c | 3 +--
 arch/x86/mm/mmio-mod.c           | 5 ++---
 2 files changed, 3 insertions(+), 5 deletions(-)

Comments

Borislav Petkov Dec. 11, 2017, 5:45 p.m. | #1
On Mon, Dec 11, 2017 at 09:50:20PM +0900, Sergey Senozhatsky wrote:
> print_symbol() uses extra stack space to sprintf() symbol
> information and then to feed that buffer to printk()
> 
>   char buffer[KSYM_SYMBOL_LEN];
> 
>   sprint_symbol(buffer, address);
>   printk(fmt, buffer);
> 
> Replace print_symbol() with a direct printk("%pS") call.
> 
> Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
> Cc: Tony Luck <tony.luck@intel.com>
> Cc: Borislav Petkov <bp@alien8.de>
> Cc: Thomas Gleixner <tglx@linutronix.de>
> ---
>  arch/x86/kernel/cpu/mcheck/mce.c | 3 +--
>  arch/x86/mm/mmio-mod.c           | 5 ++---
>  2 files changed, 3 insertions(+), 5 deletions(-)
> 
> diff --git a/arch/x86/kernel/cpu/mcheck/mce.c b/arch/x86/kernel/cpu/mcheck/mce.c
> index b1d616d08eee..8ca8f6eb32db 100644
> --- a/arch/x86/kernel/cpu/mcheck/mce.c
> +++ b/arch/x86/kernel/cpu/mcheck/mce.c
> @@ -14,7 +14,6 @@
>  #include <linux/capability.h>
>  #include <linux/miscdevice.h>
>  #include <linux/ratelimit.h>
> -#include <linux/kallsyms.h>
>  #include <linux/rcupdate.h>
>  #include <linux/kobject.h>
>  #include <linux/uaccess.h>
> @@ -235,7 +234,7 @@ static void __print_mce(struct mce *m)
>  			m->cs, m->ip);
>  
>  		if (m->cs == __KERNEL_CS)
> -			print_symbol("{%s}", m->ip);
> +			pr_cont("{%pS}", (void *)m->ip);
>  		pr_cont("\n");
>  	}
>  

For the mce.c bit above:

Acked-by: Borislav Petkov <bp@suse.de>

Thx.
Sergey Senozhatsky Dec. 12, 2017, 2:41 a.m. | #2
On (12/11/17 18:45), Borislav Petkov wrote:
> For the mce.c bit above:
> 
> Acked-by: Borislav Petkov <bp@suse.de>

thanks.

	-ss

Patch

diff --git a/arch/x86/kernel/cpu/mcheck/mce.c b/arch/x86/kernel/cpu/mcheck/mce.c
index b1d616d08eee..8ca8f6eb32db 100644
--- a/arch/x86/kernel/cpu/mcheck/mce.c
+++ b/arch/x86/kernel/cpu/mcheck/mce.c
@@ -14,7 +14,6 @@ 
 #include <linux/capability.h>
 #include <linux/miscdevice.h>
 #include <linux/ratelimit.h>
-#include <linux/kallsyms.h>
 #include <linux/rcupdate.h>
 #include <linux/kobject.h>
 #include <linux/uaccess.h>
@@ -235,7 +234,7 @@  static void __print_mce(struct mce *m)
 			m->cs, m->ip);
 
 		if (m->cs == __KERNEL_CS)
-			print_symbol("{%s}", m->ip);
+			pr_cont("{%pS}", (void *)m->ip);
 		pr_cont("\n");
 	}
 
diff --git a/arch/x86/mm/mmio-mod.c b/arch/x86/mm/mmio-mod.c
index 4d434ddb75db..2c1ecf4763c4 100644
--- a/arch/x86/mm/mmio-mod.c
+++ b/arch/x86/mm/mmio-mod.c
@@ -29,7 +29,6 @@ 
 #include <linux/slab.h>
 #include <linux/uaccess.h>
 #include <linux/io.h>
-#include <linux/kallsyms.h>
 #include <asm/pgtable.h>
 #include <linux/mmiotrace.h>
 #include <asm/e820/api.h> /* for ISA_START_ADDRESS */
@@ -123,8 +122,8 @@  static void die_kmmio_nesting_error(struct pt_regs *regs, unsigned long addr)
 	pr_emerg("unexpected fault for address: 0x%08lx, last fault for address: 0x%08lx\n",
 		 addr, my_reason->addr);
 	print_pte(addr);
-	print_symbol(KERN_EMERG "faulting IP is at %s\n", regs->ip);
-	print_symbol(KERN_EMERG "last faulting IP was at %s\n", my_reason->ip);
+	pr_emerg("faulting IP is at %pS\n", (void *)regs->ip);
+	pr_emerg("last faulting IP was at %pS\n", (void *)my_reason->ip);
 #ifdef __i386__
 	pr_emerg("eax: %08lx   ebx: %08lx   ecx: %08lx   edx: %08lx\n",
 		 regs->ax, regs->bx, regs->cx, regs->dx);