From: nicolas.pitre@linaro.org (Nicolas Pitre)
To: linux-arm-kernel@lists.infradead.org
Subject: [PATCH 1/3] ARM: debug.S: move hexbuf to a writable section
Date: Sun, 1 Oct 2017 22:06:16 -0400 [thread overview]
Message-ID: <20171002020618.23924-2-nicolas.pitre@linaro.org> (raw)
In-Reply-To: <20171002020618.23924-1-nicolas.pitre@linaro.org>
This was located in .text which is meant to be read-only. And in the XIP
case this shortcut simply doesn't work and may trigger a Flash controller
mode switch and crash the kernel. Move it to the .bss area.
Signed-off-by: Nicolas Pitre <nico@linaro.org>
---
arch/arm/kernel/debug.S | 14 +++++++++++---
1 file changed, 11 insertions(+), 3 deletions(-)
diff --git a/arch/arm/kernel/debug.S b/arch/arm/kernel/debug.S
index ea9646cc2a..423f443258 100644
--- a/arch/arm/kernel/debug.S
+++ b/arch/arm/kernel/debug.S
@@ -55,7 +55,9 @@ ENDPROC(printhex4)
ENTRY(printhex2)
mov r1, #2
-printhex: adr r2, hexbuf
+printhex: adr r2, hexbuf_rel
+ ldr r3, [r2]
+ add r2, r2, r3
add r3, r2, r1
mov r1, #0
strb r1, [r3]
@@ -71,7 +73,11 @@ printhex: adr r2, hexbuf
b printascii
ENDPROC(printhex2)
-hexbuf: .space 16
+ .pushsection .bss
+hexbuf_addr: .space 16
+ .popsection
+ .align
+hexbuf_rel: .long hexbuf_addr - .
.ltorg
@@ -120,7 +126,9 @@ ENTRY(printascii)
ENDPROC(printascii)
ENTRY(printch)
- adr r1, hexbuf
+ adr r1, hexbuf_rel
+ ldr r2, [r1]
+ add r1, r1, r2
strb r0, [r1]
mov r0, #0x03 @ SYS_WRITEC
ARM( svc #0x123456 )
--
2.9.5
next prev parent reply other threads:[~2017-10-02 2:06 UTC|newest]
Thread overview: 45+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-10-02 2:06 [PATCH 0/3] a few debug_ll fixes and improvements Nicolas Pitre
2017-10-02 2:06 ` Nicolas Pitre [this message]
2017-10-02 2:06 ` [PATCH 2/3] ARM: semihosting: use proper instruction on v7m processors Nicolas Pitre
2017-10-02 2:06 ` [PATCH 3/3] ARM: early_printk: use printascii() rather than printch() Nicolas Pitre
2017-10-02 5:20 ` Uwe Kleine-König
2017-10-02 14:09 ` Nicolas Pitre
2017-10-31 11:28 ` Chris Brandt
2017-10-31 16:22 ` Nicolas Pitre
2017-10-31 16:38 ` Robin Murphy
2017-10-31 17:06 ` Nicolas Pitre
2017-10-31 17:16 ` Russell King - ARM Linux
2017-10-31 17:48 ` Nicolas Pitre
2017-10-31 17:53 ` Russell King - ARM Linux
2017-10-31 18:15 ` Nicolas Pitre
2017-10-31 18:20 ` Russell King - ARM Linux
2017-10-31 18:35 ` Nicolas Pitre
2017-10-31 19:12 ` Chris Brandt
2017-10-31 19:28 ` Nicolas Pitre
2017-10-31 21:50 ` Russell King - ARM Linux
2017-10-31 23:35 ` Nicolas Pitre
2017-10-31 23:50 ` Russell King - ARM Linux
2017-11-02 0:09 ` Russell King - ARM Linux
2017-11-02 3:59 ` Nicolas Pitre
2017-11-02 4:16 ` Nicolas Pitre
2017-11-02 11:09 ` Russell King - ARM Linux
2017-11-02 15:12 ` Nicolas Pitre
2017-11-02 11:06 ` Chris Brandt
2017-11-02 11:20 ` Russell King - ARM Linux
2017-11-02 11:28 ` Chris Brandt
2017-11-02 13:04 ` Russell King - ARM Linux
2017-11-02 15:04 ` Nicolas Pitre
2017-11-02 15:18 ` Robin Murphy
2017-11-02 15:22 ` Russell King - ARM Linux
2017-11-02 15:25 ` Chris Brandt
2017-11-02 15:23 ` Chris Brandt
2017-11-02 15:35 ` Nicolas Pitre
2017-11-02 16:06 ` Nicolas Pitre
2017-11-02 16:38 ` Chris Brandt
2017-11-02 17:10 ` Russell King - ARM Linux
2017-11-02 17:20 ` Nicolas Pitre
2017-11-02 17:28 ` Chris Brandt
2017-11-02 18:29 ` Robin Murphy
2017-11-02 21:46 ` syntax unified, was " Nicolas Pitre
2017-11-02 15:48 ` Russell King - ARM Linux
2017-11-02 16:30 ` Chris Brandt
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