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authorFangrui Song <maskray@google.com>2021-10-28 11:39:49 -0700
committerFangrui Song <maskray@google.com>2021-10-28 11:39:49 -0700
commit68389203832ab39dd0dbaabbc4059e7fff51c29b (patch)
treef3c62c53064fd060566f1ed33688dc9c75323fe4 /sysdeps/unix/sysv/linux
parent9b7cfab1802b71763da00982f772208544cf4a95 (diff)
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riscv: Fix incorrect jal with HIDDEN_JUMPTARGET
A non-local STV_DEFAULT defined symbol is by default preemptible in a
shared object. j/jal cannot target a preemptible symbol. On other
architectures, such a jump instruction either causes PLT [BZ #18822], or
if short-ranged, sometimes rejected by the linker (but not by GNU ld's
riscv port [ld PR/28509]).

Use HIDDEN_JUMPTARGET to target a non-preemptible symbol instead.

With this patch, ld.so and libc.so can be linked with LLD if source
files are compiled/assembled with -mno-relax/-Wa,-mno-relax.

Acked-by: Palmer Dabbelt <palmer@dabbelt.com>
Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
Diffstat (limited to 'sysdeps/unix/sysv/linux')
-rw-r--r--sysdeps/unix/sysv/linux/riscv/setcontext.S5
1 files changed, 3 insertions, 2 deletions
diff --git a/sysdeps/unix/sysv/linux/riscv/setcontext.S b/sysdeps/unix/sysv/linux/riscv/setcontext.S
index 9510518750..e44a68aad4 100644
--- a/sysdeps/unix/sysv/linux/riscv/setcontext.S
+++ b/sysdeps/unix/sysv/linux/riscv/setcontext.S
@@ -95,6 +95,7 @@ LEAF (__setcontext)
 99:	j	__syscall_error
 
 END (__setcontext)
+libc_hidden_def (__setcontext)
 weak_alias (__setcontext, setcontext)
 
 LEAF (__start_context)
@@ -108,7 +109,7 @@ LEAF (__start_context)
 	/* Invoke subsequent context if present, else exit(0).  */
 	mv	a0, s2
 	beqz	s2, 1f
-	jal	__setcontext
-1:	j	exit
+	jal	HIDDEN_JUMPTARGET (__setcontext)
+1:	j	HIDDEN_JUMPTARGET (exit)
 
 END (__start_context)