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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 hace 18 años
padre
commit
52eb053b71
Se han modificado 3 ficheros con 11 adiciones y 5 borrados
  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"					\