From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tetsuyuki Kobayashi Date: Fri, 05 Apr 2013 19:04:27 +0900 Subject: [U-Boot] [PATCH v2] BUGFIX: arm: data abort in get_bad_stack_swi In-Reply-To: <20130405090450.7f7a4624@lilith> References: <1365051167-24742-1-git-send-email-koba@kmckk.co.jp> <1365126314-26328-1-git-send-email-koba@kmckk.co.jp> <20130405090450.7f7a4624@lilith> Message-ID: <515EA1AB.7020702@kmckk.co.jp> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de Hi Albert (04/05/2013 04:04 PM), Albert ARIBAUD wrote: > Hi Tetsuyuki, > > On Fri, 5 Apr 2013 10:45:14 +0900, Tetsuyuki Kobayashi > wrote: > >> When swi instruction is executed, it is expected to get message >> "software interrupt" in console and dump registers and reboot, as >> do_software_interrupt() in arch/arm/lib/interrupts.c. >> But, actually it causes data abort accessing wrong address in get_bad_stack_swi >> macro in arch/arm/cpu/v7/start.S. >> This patch fixes this problem. >> >> The same mistake in arch/arm/cpu/{arm1136,arm1176,pxa}/start.S. >> >> Signed-off-by: Tetsuyuki Kobayashi >> --- >> Changes for v2: >> - added arch/arm/cpu/{arm1136,arm1176,pxa}/start.S >> (But not tested, because I don't have test boards of them) >> arm/arm/cpu/armv7/start.S is tested on KZM-A9-GT board. >> >> arch/arm/cpu/arm1136/start.S | 2 +- >> arch/arm/cpu/arm1176/start.S | 2 +- >> arch/arm/cpu/armv7/start.S | 2 +- >> arch/arm/cpu/pxa/start.S | 2 +- >> 4 files changed, 4 insertions(+), 4 deletions(-) >> >> diff --git a/arch/arm/cpu/arm1136/start.S b/arch/arm/cpu/arm1136/start.S >> index eba2324..7b9db2b 100644 >> --- a/arch/arm/cpu/arm1136/start.S >> +++ b/arch/arm/cpu/arm1136/start.S >> @@ -392,7 +392,7 @@ cpu_init_crit: >> str r0, [r13] @ save R0's value. >> ldr r0, IRQ_STACK_START_IN @ get data regions start >> str lr, [r0] @ save caller lr in position 0 of saved stack >> - mrs r0, spsr @ get the spsr >> + mrs lr, spsr @ get the spsr >> str lr, [r0, #4] @ save spsr in position 1 of saved stack >> ldr r0, [r13] @ restore r0 >> add r13, r13, #4 @ pop stack entry > > Sorry for not checking this in V1, but I see that get_bad_stack_swi does > not preserve lr, so when bad_save_user_regs is expanded, it will save > the wrong value for lr. You need to restore lr from [r0] before you > restore r0 from [r13]. Thank you, I was not aware that. The dumped lr value was wrong. I am going to post V3 patch for all 4 files. > >> diff --git a/arch/arm/cpu/arm1176/start.S b/arch/arm/cpu/arm1176/start.S > >> diff --git a/arch/arm/cpu/armv7/start.S b/arch/arm/cpu/armv7/start.S > >> diff --git a/arch/arm/cpu/pxa/start.S b/arch/arm/cpu/pxa/start.S > > Ditto for all four files, of course. > > Amicalement, >