diff mbox

S390: Clobber also r14 in TLS_LD, TLS_GD macros on 31bit.

Message ID 876ee185-e900-6442-393f-8619cc55d76f@linux.vnet.ibm.com
State Committed
Headers

Commit Message

Stefan Liebler March 29, 2017, 9:22 a.m. UTC 
  Hi,

This patch also clobbers r14 in TLS_LD, TLS_GD macros on 31bit.
This ensures that r14 isn't used to save and restore r12 while
r14 is clobbered by the bas-instruction.

As note:
r12 can't be clobbered as gcc would fail with:
error: PIC register clobbered by ‘12’ in ‘asm’

For 64bit this fix was already done in 2004 in the
commit b80af23ac6973e69df6cd23d221fa44fffb21e17.

Bye
Stefan

ChangeLog:

	* sysdeps/s390/s390-32/tls-macros.h (TLS_LD, TLS_GD):
	Clobber also r14.

Comments

Stefan Liebler April 3, 2017, 1:50 p.m. UTC | #1 
On 03/29/2017 11:22 AM, Stefan Liebler wrote:
> Hi,
>
> This patch also clobbers r14 in TLS_LD, TLS_GD macros on 31bit.
> This ensures that r14 isn't used to save and restore r12 while
> r14 is clobbered by the bas-instruction.
>
> As note:
> r12 can't be clobbered as gcc would fail with:
> error: PIC register clobbered by ‘12’ in ‘asm’
>
> For 64bit this fix was already done in 2004 in the
> commit b80af23ac6973e69df6cd23d221fa44fffb21e17.
>
> Bye
> Stefan
>
> ChangeLog:
>
>     * sysdeps/s390/s390-32/tls-macros.h (TLS_LD, TLS_GD):
>     Clobber also r14.

Any objection?
Otherwise, I'll commit it tomorrow.

Bye
Stefan
Stefan Liebler April 4, 2017, 11:18 a.m. UTC | #2 
On 04/03/2017 03:50 PM, Stefan Liebler wrote:
> On 03/29/2017 11:22 AM, Stefan Liebler wrote:
>> Hi,
>>
>> This patch also clobbers r14 in TLS_LD, TLS_GD macros on 31bit.
>> This ensures that r14 isn't used to save and restore r12 while
>> r14 is clobbered by the bas-instruction.
>>
>> As note:
>> r12 can't be clobbered as gcc would fail with:
>> error: PIC register clobbered by ‘12’ in ‘asm’
>>
>> For 64bit this fix was already done in 2004 in the
>> commit b80af23ac6973e69df6cd23d221fa44fffb21e17.
>>
>> Bye
>> Stefan
>>
>> ChangeLog:
>>
>>     * sysdeps/s390/s390-32/tls-macros.h (TLS_LD, TLS_GD):
>>     Clobber also r14.
>
> Any objection?
> Otherwise, I'll commit it tomorrow.
>
> Bye
> Stefan
>
Committed.
diff mbox

Patch

commit 3f102d08af514c1cd4094c2feaca02546548de36
Author: Stefan Liebler <stli@linux.vnet.ibm.com>
Date:   Wed Mar 29 11:07:02 2017 +0200

    S390: Clobber also r14 in TLS_LD, TLS_GD macros on 31bit.
    
    This patch also clobbers r14 in TLS_LD, TLS_GD macros on 31bit.
    This ensures that r14 isn't used to save and restore r12 while
    r14 is clobbered by the bas-instruction.
    
    As note:
    r12 can't be clobbered as gcc would fail with:
    error: PIC register clobbered by ‘12’ in ‘asm’
    
    For 64bit this fix was already done in 2004 in the
    commit b80af23ac6973e69df6cd23d221fa44fffb21e17.
    
    ChangeLog:
    
    	* sysdeps/s390/s390-32/tls-macros.h (TLS_LD, TLS_GD):
    	Clobber also r14.

diff --git a/sysdeps/s390/s390-32/tls-macros.h b/sysdeps/s390/s390-32/tls-macros.h
index 09b42aa..a4c5fff 100644
--- a/sysdeps/s390/s390-32/tls-macros.h
+++ b/sysdeps/s390/s390-32/tls-macros.h
@@ -47,7 +47,7 @@ 
 	      "alr %0,%%r2\n\t"						      \
 	      "lr %%r12,%1"						      \
 	      : "=&a" (__offset), "=&a" (__save12)			      \
-	      : : "cc", "0", "1", "2", "3", "4", "5" );			      \
+	      : : "cc", "0", "1", "2", "3", "4", "5", "14");		      \
      (int *) (__builtin_thread_pointer() + __offset); })
 #else
 # define TLS_LD(x) \
@@ -63,7 +63,8 @@ 
 	      "bas %%r14,0(%%r1):tls_ldcall:" #x "\n\t"			      \
 	      "l %0,12(%0)\n\t"						      \
 	      "alr %0,%%r2"						      \
-	      : "=&a" (__offset) : : "cc", "0", "1", "2", "3", "4", "5", "12" ); \
+	      : "=&a" (__offset)					      \
+	      : : "cc", "0", "1", "2", "3", "4", "5", "12", "14");	      \
      (int *) (__builtin_thread_pointer() + __offset); })
 #endif
 
@@ -83,7 +84,7 @@ 
 	      "lr %0,%%r2\n\t"						      \
 	      "lr %%r12,%1"						      \
 	      : "=&a" (__offset), "=&a" (__save12)			      \
-	      : : "cc", "0", "1", "2", "3", "4", "5" );			      \
+	      : : "cc", "0", "1", "2", "3", "4", "5", "14");		      \
      (int *) (__builtin_thread_pointer() + __offset); })
 #else
 # define TLS_GD(x) \
@@ -97,6 +98,7 @@ 
 	      "l %%r2,8(%0)\n\t"					      \
 	      "bas %%r14,0(%%r1):tls_gdcall:" #x "\n\t"			      \
 	      "lr %0,%%r2"						      \
-	      : "=&a" (__offset) : : "cc", "0", "1", "2", "3", "4", "5", "12" ); \
+	      : "=&a" (__offset)					      \
+	      : : "cc", "0", "1", "2", "3", "4", "5", "12", "14");	      \
      (int *) (__builtin_thread_pointer() + __offset); })
 #endif