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[SPARC64]: Fix linkage of enormous kernels.

This was found by make randconfig

If the kernel .text is very large, the .fixup section branches
are too far away to be relocated correctly.

Use "sethi %hi(label), reg; jmpl reg + %lo(label); %g0" sequence
instead of the branch to fix this.

There is another case in switch_to() involving a branch, which
is fixed similarly.

Signed-off-by: David S. Miller <davem@davemloft.net>
David S. Miller 17 years ago
parent
commit
52eb053b71
3 changed files with 11 additions and 5 deletions
  1. 4 2
      include/asm-sparc64/futex.h
  2. 3 1
      include/asm-sparc64/system.h
  3. 4 2
      include/asm-sparc64/uaccess.h

+ 4 - 2
include/asm-sparc64/futex.h

@@ -17,7 +17,8 @@
 	"3:\n"						\
 	"	.section .fixup,#alloc,#execinstr\n"	\
 	"	.align	4\n"				\
-	"4:	ba	3b\n"				\
+	"4:	sethi	%%hi(3b), %0\n"			\
+	"	jmpl	%0 + %%lo(3b), %%g0\n"		\
 	"	 mov	%5, %0\n"			\
 	"	.previous\n"				\
 	"	.section __ex_table,\"a\"\n"		\
@@ -91,7 +92,8 @@ futex_atomic_cmpxchg_inatomic(int __user *uaddr, int oldval, int newval)
 	"2:\n"
 	"	.section .fixup,#alloc,#execinstr\n"
 	"	.align	4\n"
-	"3:	ba	2b\n"
+	"3:	sethi	%%hi(2b), %0\n"
+	"	jmpl	%0 + %%lo(2b), %%g0\n"
 	"	 mov	%4, %0\n"
 	"	.previous\n"
 	"	.section __ex_table,\"a\"\n"

+ 3 - 1
include/asm-sparc64/system.h

@@ -178,7 +178,9 @@ do {	if (test_thread_flag(TIF_PERFCTR)) {				\
 	"ldx	[%%g6 + %9], %%g4\n\t"					\
 	"brz,pt %%o7, 1f\n\t"						\
 	" mov	%%g7, %0\n\t"						\
-	"b,a ret_from_syscall\n\t"					\
+	"sethi	%%hi(ret_from_syscall), %%g1\n\t"			\
+	"jmpl	%%g1 + %%lo(ret_from_syscall), %%g0\n\t"		\
+	" nop\n\t"							\
 	"1:\n\t"							\
 	: "=&r" (last), "=r" (current), "=r" (current_thread_info_reg),	\
 	  "=r" (__local_per_cpu_offset)					\

+ 4 - 2
include/asm-sparc64/uaccess.h

@@ -123,7 +123,8 @@ __asm__ __volatile__(							\
 	".section .fixup,#alloc,#execinstr\n\t"				\
 	".align	4\n"							\
 "3:\n\t"								\
-	"b	2b\n\t"							\
+	"sethi	%%hi(2b), %0\n\t"					\
+	"jmpl	%0 + %%lo(2b), %%g0\n\t"				\
 	" mov	%3, %0\n\n\t"						\
 	".previous\n\t"							\
 	".section __ex_table,\"a\"\n\t"					\
@@ -165,8 +166,9 @@ __asm__ __volatile__(							\
 	".section .fixup,#alloc,#execinstr\n\t"				\
 	".align	4\n"							\
 "3:\n\t"								\
+	"sethi	%%hi(2b), %0\n\t"					\
 	"clr	%1\n\t"							\
-	"b	2b\n\t"							\
+	"jmpl	%0 + %%lo(2b), %%g0\n\t"				\
 	" mov	%3, %0\n\n\t"						\
 	".previous\n\t"							\
 	".section __ex_table,\"a\"\n\t"					\