Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]


Groups > linux.kernel > #1620294 > unrolled thread

[PATCH 4.9 048/152] MIPS: End spinlocks with .insn

Started byGreg Kroah-Hartman <gregkh@linuxfoundation.org>
First post2017-04-10 18:50 +0200
Last post2017-04-10 18:50 +0200
Articles 1 — 1 participant

Back to article view | Back to linux.kernel

This discussion starts older than the indexed window; earlier articles aren't shown. The article labeled Started by below is the oldest one visible, not the original post.


Contents

  [PATCH 4.9 048/152] MIPS: End spinlocks with .insn Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-04-10 18:50 +0200

#1620294 — [PATCH 4.9 048/152] MIPS: End spinlocks with .insn

FromGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Date2017-04-10 18:50 +0200
Subject[PATCH 4.9 048/152] MIPS: End spinlocks with .insn
Message-ID<tuKFU-3ds-129@gated-at.bofh.it>
4.9-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Paul Burton <paul.burton@imgtec.com>

commit 4b5347a24a0f2d3272032c120664b484478455de upstream.

When building for microMIPS we need to ensure that the assembler always
knows that there is code at the target of a branch or jump. Recent
toolchains will fail to link a microMIPS kernel when this isn't the case
due to what it thinks is a branch to non-microMIPS code.

mips-mti-linux-gnu-ld kernel/built-in.o: .spinlock.text+0x2fc: Unsupported branch between ISA modes.
mips-mti-linux-gnu-ld final link failed: Bad value

This is due to inline assembly labels in spinlock.h not being followed
by an instruction mnemonic, either due to a .subsection pseudo-op or the
end of the inline asm block.

Fix this with a .insn direction after such labels.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Reviewed-by: Maciej W. Rozycki <macro@imgtec.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/15325/
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 arch/mips/include/asm/spinlock.h |    8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

--- a/arch/mips/include/asm/spinlock.h
+++ b/arch/mips/include/asm/spinlock.h
@@ -127,7 +127,7 @@ static inline void arch_spin_lock(arch_s
 		"	andi	%[ticket], %[ticket], 0xffff		\n"
 		"	bne	%[ticket], %[my_ticket], 4f		\n"
 		"	 subu	%[ticket], %[my_ticket], %[ticket]	\n"
-		"2:							\n"
+		"2:	.insn						\n"
 		"	.subsection 2					\n"
 		"4:	andi	%[ticket], %[ticket], 0xffff		\n"
 		"	sll	%[ticket], 5				\n"
@@ -202,7 +202,7 @@ static inline unsigned int arch_spin_try
 		"	sc	%[ticket], %[ticket_ptr]		\n"
 		"	beqz	%[ticket], 1b				\n"
 		"	 li	%[ticket], 1				\n"
-		"2:							\n"
+		"2:	.insn						\n"
 		"	.subsection 2					\n"
 		"3:	b	2b					\n"
 		"	 li	%[ticket], 0				\n"
@@ -382,7 +382,7 @@ static inline int arch_read_trylock(arch
 		"	.set	reorder					\n"
 		__WEAK_LLSC_MB
 		"	li	%2, 1					\n"
-		"2:							\n"
+		"2:	.insn						\n"
 		: "=" GCC_OFF_SMALL_ASM() (rw->lock), "=&r" (tmp), "=&r" (ret)
 		: GCC_OFF_SMALL_ASM() (rw->lock)
 		: "memory");
@@ -422,7 +422,7 @@ static inline int arch_write_trylock(arc
 			"	lui	%1, 0x8000			\n"
 			"	sc	%1, %0				\n"
 			"	li	%2, 1				\n"
-			"2:						\n"
+			"2:	.insn					\n"
 			: "=" GCC_OFF_SMALL_ASM() (rw->lock), "=&r" (tmp),
 			  "=&r" (ret)
 			: GCC_OFF_SMALL_ASM() (rw->lock)

[toc] | [standalone]


Back to top | Article view | linux.kernel


csiph-web