* [PATCH 1/5] Use SIGBUS for unalinged access instead of SIGILL
2010-07-19 8:53 [PATCH 0/5] ARM: fix exceptions handling Kirill A. Shutsemov
@ 2010-07-19 8:53 ` Kirill A. Shutsemov
2010-07-19 8:53 ` [PATCH 2/5] Add 'code' parameter for hook_fault_code() Kirill A. Shutsemov
` (3 subsequent siblings)
4 siblings, 0 replies; 11+ messages in thread
From: Kirill A. Shutsemov @ 2010-07-19 8:53 UTC (permalink / raw)
To: linux-arm-kernel
From: Kirill A. Shutemov <kirill@shutemov.name>
POSIX specify to use signal SIGBUS with code BUS_ADRALN for invalid
address alignment.
Signed-off-by: Kirill A. Shutemov <kirill@shutemov.name>
---
arch/arm/mm/alignment.c | 4 ++--
arch/arm/mm/fault.c | 4 ++--
2 files changed, 4 insertions(+), 4 deletions(-)
diff --git a/arch/arm/mm/alignment.c b/arch/arm/mm/alignment.c
index 6f98c35..53a6096 100644
--- a/arch/arm/mm/alignment.c
+++ b/arch/arm/mm/alignment.c
@@ -924,8 +924,8 @@ static int __init alignment_init(void)
ai_usermode = UM_FIXUP;
}
- hook_fault_code(1, do_alignment, SIGILL, "alignment exception");
- hook_fault_code(3, do_alignment, SIGILL, "alignment exception");
+ hook_fault_code(1, do_alignment, SIGBUS, "alignment exception");
+ hook_fault_code(3, do_alignment, SIGBUS, "alignment exception");
return 0;
}
diff --git a/arch/arm/mm/fault.c b/arch/arm/mm/fault.c
index cbfb2ed..ce6f3a4 100644
--- a/arch/arm/mm/fault.c
+++ b/arch/arm/mm/fault.c
@@ -463,9 +463,9 @@ static struct fsr_info {
* defines these to be "precise" aborts.
*/
{ do_bad, SIGSEGV, 0, "vector exception" },
- { do_bad, SIGILL, BUS_ADRALN, "alignment exception" },
+ { do_bad, SIGBUS, BUS_ADRALN, "alignment exception" },
{ do_bad, SIGKILL, 0, "terminal exception" },
- { do_bad, SIGILL, BUS_ADRALN, "alignment exception" },
+ { do_bad, SIGBUS, BUS_ADRALN, "alignment exception" },
/* Do we need runtime check ? */
#if __LINUX_ARM_ARCH__ < 6
{ do_bad, SIGBUS, 0, "external abort on linefetch" },
--
1.7.1.1
^ permalink raw reply related [flat|nested] 11+ messages in thread* [PATCH 2/5] Add 'code' parameter for hook_fault_code()
2010-07-19 8:53 [PATCH 0/5] ARM: fix exceptions handling Kirill A. Shutsemov
2010-07-19 8:53 ` [PATCH 1/5] Use SIGBUS for unalinged access instead of SIGILL Kirill A. Shutsemov
@ 2010-07-19 8:53 ` Kirill A. Shutsemov
2010-07-27 9:35 ` Russell King - ARM Linux
2010-07-19 8:53 ` [PATCH 3/5] Check arch version and modify fsr_info[] depends on it at runtime Kirill A. Shutsemov
` (2 subsequent siblings)
4 siblings, 1 reply; 11+ messages in thread
From: Kirill A. Shutsemov @ 2010-07-19 8:53 UTC (permalink / raw)
To: linux-arm-kernel
From: Kirill A. Shutemov <kirill@shutemov.name>
Add one more parameter to hook_fault_code() to be able to set 'code'
field of struct fsr_info.
Signed-off-by: Kirill A. Shutemov <kirill@shutemov.name>
---
arch/arm/include/asm/system.h | 2 +-
arch/arm/mach-integrator/pci_v3.c | 8 ++++----
arch/arm/mach-iop13xx/pci.c | 2 +-
arch/arm/mach-ixp2000/pci.c | 2 +-
arch/arm/mach-ixp23xx/pci.c | 2 +-
arch/arm/mach-ixp4xx/common-pci.c | 3 ++-
arch/arm/mach-ks8695/pci.c | 4 ++--
arch/arm/mm/alignment.c | 6 ++++--
arch/arm/mm/fault.c | 14 ++++++++------
arch/arm/plat-iop/pci.c | 2 +-
10 files changed, 25 insertions(+), 20 deletions(-)
diff --git a/arch/arm/include/asm/system.h b/arch/arm/include/asm/system.h
index 5f4f480..8ba1ccf 100644
--- a/arch/arm/include/asm/system.h
+++ b/arch/arm/include/asm/system.h
@@ -83,7 +83,7 @@ void arm_notify_die(const char *str, struct pt_regs *regs, struct siginfo *info,
void hook_fault_code(int nr, int (*fn)(unsigned long, unsigned int,
struct pt_regs *),
- int sig, const char *name);
+ int sig, int code, const char *name);
#define xchg(ptr,x) \
((__typeof__(*(ptr)))__xchg((unsigned long)(x),(ptr),sizeof(*(ptr))))
diff --git a/arch/arm/mach-integrator/pci_v3.c b/arch/arm/mach-integrator/pci_v3.c
index 9cef059..6467d99 100644
--- a/arch/arm/mach-integrator/pci_v3.c
+++ b/arch/arm/mach-integrator/pci_v3.c
@@ -505,10 +505,10 @@ void __init pci_v3_preinit(void)
/*
* Hook in our fault handler for PCI errors
*/
- hook_fault_code(4, v3_pci_fault, SIGBUS, "external abort on linefetch");
- hook_fault_code(6, v3_pci_fault, SIGBUS, "external abort on linefetch");
- hook_fault_code(8, v3_pci_fault, SIGBUS, "external abort on non-linefetch");
- hook_fault_code(10, v3_pci_fault, SIGBUS, "external abort on non-linefetch");
+ hook_fault_code(4, v3_pci_fault, SIGBUS, 0, "external abort on linefetch");
+ hook_fault_code(6, v3_pci_fault, SIGBUS, 0, "external abort on linefetch");
+ hook_fault_code(8, v3_pci_fault, SIGBUS, 0, "external abort on non-linefetch");
+ hook_fault_code(10, v3_pci_fault, SIGBUS, 0, "external abort on non-linefetch");
spin_lock_irqsave(&v3_lock, flags);
diff --git a/arch/arm/mach-iop13xx/pci.c b/arch/arm/mach-iop13xx/pci.c
index 6d5a908..773ea0c 100644
--- a/arch/arm/mach-iop13xx/pci.c
+++ b/arch/arm/mach-iop13xx/pci.c
@@ -987,7 +987,7 @@ void __init iop13xx_pci_init(void)
iop13xx_atux_setup();
}
- hook_fault_code(16+6, iop13xx_pci_abort, SIGBUS,
+ hook_fault_code(16+6, iop13xx_pci_abort, SIGBUS, 0,
"imprecise external abort");
}
diff --git a/arch/arm/mach-ixp2000/pci.c b/arch/arm/mach-ixp2000/pci.c
index 90771ca..853fd90 100644
--- a/arch/arm/mach-ixp2000/pci.c
+++ b/arch/arm/mach-ixp2000/pci.c
@@ -209,7 +209,7 @@ ixp2000_pci_preinit(void)
"the needed workaround has not been configured in");
#endif
- hook_fault_code(16+6, ixp2000_pci_abort_handler, SIGBUS,
+ hook_fault_code(16+6, ixp2000_pci_abort_handler, SIGBUS, 0
"PCI config cycle to non-existent device");
}
diff --git a/arch/arm/mach-ixp23xx/pci.c b/arch/arm/mach-ixp23xx/pci.c
index 4b0e598..563819a 100644
--- a/arch/arm/mach-ixp23xx/pci.c
+++ b/arch/arm/mach-ixp23xx/pci.c
@@ -229,7 +229,7 @@ void __init ixp23xx_pci_preinit(void)
{
ixp23xx_pci_common_init();
- hook_fault_code(16+6, ixp23xx_pci_abort_handler, SIGBUS,
+ hook_fault_code(16+6, ixp23xx_pci_abort_handler, SIGBUS, 0,
"PCI config cycle to non-existent device");
*IXP23XX_PCI_ADDR_EXT = 0x0000e000;
diff --git a/arch/arm/mach-ixp4xx/common-pci.c b/arch/arm/mach-ixp4xx/common-pci.c
index e318153..f4fbb5e 100644
--- a/arch/arm/mach-ixp4xx/common-pci.c
+++ b/arch/arm/mach-ixp4xx/common-pci.c
@@ -382,7 +382,8 @@ void __init ixp4xx_pci_preinit(void)
/* hook in our fault handler for PCI errors */
- hook_fault_code(16+6, abort_handler, SIGBUS, "imprecise external abort");
+ hook_fault_code(16+6, abort_handler, SIGBUS, 0,
+ "imprecise external abort");
pr_debug("setup PCI-AHB(inbound) and AHB-PCI(outbound) address mappings\n");
diff --git a/arch/arm/mach-ks8695/pci.c b/arch/arm/mach-ks8695/pci.c
index 7849966..5fcd082 100644
--- a/arch/arm/mach-ks8695/pci.c
+++ b/arch/arm/mach-ks8695/pci.c
@@ -268,8 +268,8 @@ static void __init ks8695_pci_preinit(void)
__raw_writel(0, KS8695_PCI_VA + KS8695_PIOBAC);
/* hook in fault handlers */
- hook_fault_code(8, ks8695_pci_fault, SIGBUS, "external abort on non-linefetch");
- hook_fault_code(10, ks8695_pci_fault, SIGBUS, "external abort on non-linefetch");
+ hook_fault_code(8, ks8695_pci_fault, SIGBUS, 0, "external abort on non-linefetch");
+ hook_fault_code(10, ks8695_pci_fault, SIGBUS, 0, "external abort on non-linefetch");
}
static void ks8695_show_pciregs(void)
diff --git a/arch/arm/mm/alignment.c b/arch/arm/mm/alignment.c
index 53a6096..77cfdbe 100644
--- a/arch/arm/mm/alignment.c
+++ b/arch/arm/mm/alignment.c
@@ -924,8 +924,10 @@ static int __init alignment_init(void)
ai_usermode = UM_FIXUP;
}
- hook_fault_code(1, do_alignment, SIGBUS, "alignment exception");
- hook_fault_code(3, do_alignment, SIGBUS, "alignment exception");
+ hook_fault_code(1, do_alignment, SIGBUS, BUS_ADRALN,
+ "alignment exception");
+ hook_fault_code(3, do_alignment, SIGBUS, BUS_ADRALN,
+ "alignment exception");
return 0;
}
diff --git a/arch/arm/mm/fault.c b/arch/arm/mm/fault.c
index ce6f3a4..84131c8 100644
--- a/arch/arm/mm/fault.c
+++ b/arch/arm/mm/fault.c
@@ -508,13 +508,15 @@ static struct fsr_info {
void __init
hook_fault_code(int nr, int (*fn)(unsigned long, unsigned int, struct pt_regs *),
- int sig, const char *name)
+ int sig, int code, const char *name)
{
- if (nr >= 0 && nr < ARRAY_SIZE(fsr_info)) {
- fsr_info[nr].fn = fn;
- fsr_info[nr].sig = sig;
- fsr_info[nr].name = name;
- }
+ if (nr < 0 || nr >= ARRAY_SIZE(fsr_info))
+ BUG();
+
+ fsr_info[nr].fn = fn;
+ fsr_info[nr].sig = sig;
+ fsr_info[nr].code = code;
+ fsr_info[nr].name = name;
}
/*
diff --git a/arch/arm/plat-iop/pci.c b/arch/arm/plat-iop/pci.c
index ce31f31..43f2b15 100644
--- a/arch/arm/plat-iop/pci.c
+++ b/arch/arm/plat-iop/pci.c
@@ -359,7 +359,7 @@ static void __init iop3xx_atu_debug(void)
DBG("ATU: IOP3XX_ATUCMD=0x%04x\n", *IOP3XX_ATUCMD);
DBG("ATU: IOP3XX_ATUCR=0x%08x\n", *IOP3XX_ATUCR);
- hook_fault_code(16+6, iop3xx_pci_abort, SIGBUS, "imprecise external abort");
+ hook_fault_code(16+6, iop3xx_pci_abort, SIGBUS, 0, "imprecise external abort");
}
/* for platforms that might be host-bus-adapters */
--
1.7.1.1
^ permalink raw reply related [flat|nested] 11+ messages in thread* [PATCH 2/5] Add 'code' parameter for hook_fault_code()
2010-07-19 8:53 ` [PATCH 2/5] Add 'code' parameter for hook_fault_code() Kirill A. Shutsemov
@ 2010-07-27 9:35 ` Russell King - ARM Linux
2010-07-27 9:42 ` Kirill A. Shutemov
0 siblings, 1 reply; 11+ messages in thread
From: Russell King - ARM Linux @ 2010-07-27 9:35 UTC (permalink / raw)
To: linux-arm-kernel
On Mon, Jul 19, 2010 at 11:53:22AM +0300, Kirill A. Shutsemov wrote:
> diff --git a/arch/arm/mach-ixp2000/pci.c b/arch/arm/mach-ixp2000/pci.c
> index 90771ca..853fd90 100644
> --- a/arch/arm/mach-ixp2000/pci.c
> +++ b/arch/arm/mach-ixp2000/pci.c
> @@ -209,7 +209,7 @@ ixp2000_pci_preinit(void)
> "the needed workaround has not been configured in");
> #endif
>
> - hook_fault_code(16+6, ixp2000_pci_abort_handler, SIGBUS,
> + hook_fault_code(16+6, ixp2000_pci_abort_handler, SIGBUS, 0
> "PCI config cycle to non-existent device");
This is broken - can you submit a fixed version please?
^ permalink raw reply [flat|nested] 11+ messages in thread
* [PATCH 2/5] Add 'code' parameter for hook_fault_code()
2010-07-27 9:35 ` Russell King - ARM Linux
@ 2010-07-27 9:42 ` Kirill A. Shutemov
0 siblings, 0 replies; 11+ messages in thread
From: Kirill A. Shutemov @ 2010-07-27 9:42 UTC (permalink / raw)
To: linux-arm-kernel
On Tue, Jul 27, 2010 at 10:35:37AM +0100, Russell King - ARM Linux wrote:
> On Mon, Jul 19, 2010 at 11:53:22AM +0300, Kirill A. Shutsemov wrote:
> > diff --git a/arch/arm/mach-ixp2000/pci.c b/arch/arm/mach-ixp2000/pci.c
> > index 90771ca..853fd90 100644
> > --- a/arch/arm/mach-ixp2000/pci.c
> > +++ b/arch/arm/mach-ixp2000/pci.c
> > @@ -209,7 +209,7 @@ ixp2000_pci_preinit(void)
> > "the needed workaround has not been configured in");
> > #endif
> >
> > - hook_fault_code(16+6, ixp2000_pci_abort_handler, SIGBUS,
> > + hook_fault_code(16+6, ixp2000_pci_abort_handler, SIGBUS, 0
> > "PCI config cycle to non-existent device");
>
> This is broken - can you submit a fixed version please?
Done.
--
Kirill A. Shutemov
^ permalink raw reply [flat|nested] 11+ messages in thread
* [PATCH 3/5] Check arch version and modify fsr_info[] depends on it at runtime
2010-07-19 8:53 [PATCH 0/5] ARM: fix exceptions handling Kirill A. Shutsemov
2010-07-19 8:53 ` [PATCH 1/5] Use SIGBUS for unalinged access instead of SIGILL Kirill A. Shutsemov
2010-07-19 8:53 ` [PATCH 2/5] Add 'code' parameter for hook_fault_code() Kirill A. Shutsemov
@ 2010-07-19 8:53 ` Kirill A. Shutsemov
2010-07-19 8:53 ` [PATCH 4/5] ARMv6K and ARMv7 use fault statuses 3 and 6 as Access Flag fault Kirill A. Shutsemov
2010-07-19 8:53 ` [PATCH 5/5] Workaround infinity loop in handling of translation faults Kirill A. Shutsemov
4 siblings, 0 replies; 11+ messages in thread
From: Kirill A. Shutsemov @ 2010-07-19 8:53 UTC (permalink / raw)
To: linux-arm-kernel
From: Kirill A. Shutemov <kirill@shutemov.name>
Signed-off-by: Kirill A. Shutemov <kirill@shutemov.name>
---
arch/arm/mm/fault.c | 16 +++++++++++-----
1 files changed, 11 insertions(+), 5 deletions(-)
diff --git a/arch/arm/mm/fault.c b/arch/arm/mm/fault.c
index 84131c8..345a3c9 100644
--- a/arch/arm/mm/fault.c
+++ b/arch/arm/mm/fault.c
@@ -466,12 +466,7 @@ static struct fsr_info {
{ do_bad, SIGBUS, BUS_ADRALN, "alignment exception" },
{ do_bad, SIGKILL, 0, "terminal exception" },
{ do_bad, SIGBUS, BUS_ADRALN, "alignment exception" },
-/* Do we need runtime check ? */
-#if __LINUX_ARM_ARCH__ < 6
{ do_bad, SIGBUS, 0, "external abort on linefetch" },
-#else
- { do_translation_fault, SIGSEGV, SEGV_MAPERR, "I-cache maintenance fault" },
-#endif
{ do_translation_fault, SIGSEGV, SEGV_MAPERR, "section translation fault" },
{ do_bad, SIGBUS, 0, "external abort on linefetch" },
{ do_page_fault, SIGSEGV, SEGV_MAPERR, "page translation fault" },
@@ -596,3 +591,14 @@ do_PrefetchAbort(unsigned long addr, unsigned int ifsr, struct pt_regs *regs)
arm_notify_die("", regs, &info, ifsr, 0);
}
+static int __init exceptions_init(void)
+{
+ if (cpu_architecture() >= CPU_ARCH_ARMv6) {
+ hook_fault_code(4, do_translation_fault, SIGSEGV, SEGV_MAPERR,
+ "I-cache maintenance fault");
+ }
+
+ return 0;
+}
+
+arch_initcall(exceptions_init);
--
1.7.1.1
^ permalink raw reply related [flat|nested] 11+ messages in thread* [PATCH 4/5] ARMv6K and ARMv7 use fault statuses 3 and 6 as Access Flag fault
2010-07-19 8:53 [PATCH 0/5] ARM: fix exceptions handling Kirill A. Shutsemov
` (2 preceding siblings ...)
2010-07-19 8:53 ` [PATCH 3/5] Check arch version and modify fsr_info[] depends on it at runtime Kirill A. Shutsemov
@ 2010-07-19 8:53 ` Kirill A. Shutsemov
2010-07-19 10:11 ` Sergei Shtylyov
2010-07-19 8:53 ` [PATCH 5/5] Workaround infinity loop in handling of translation faults Kirill A. Shutsemov
4 siblings, 1 reply; 11+ messages in thread
From: Kirill A. Shutsemov @ 2010-07-19 8:53 UTC (permalink / raw)
To: linux-arm-kernel
From: Kirill A. Shutemov <kirill@shutemov.name>
Statuses 3 (0b00011) and 6 (0x00110) of DFSR are Access Flags faults on
ARMv6K and ARMv7. Let's patch fsr_info[] at runtime if we are on ARMv7
or later.
Unfortunately, we don't have runtime check for 'K' extension, so we
can't check for it.
Signed-off-by: Kirill A. Shutemov <kirill@shutemov.name>
---
arch/arm/mm/alignment.c | 14 ++++++++++++--
arch/arm/mm/fault.c | 11 +++++++++++
2 files changed, 23 insertions(+), 2 deletions(-)
diff --git a/arch/arm/mm/alignment.c b/arch/arm/mm/alignment.c
index 77cfdbe..d073b64 100644
--- a/arch/arm/mm/alignment.c
+++ b/arch/arm/mm/alignment.c
@@ -926,8 +926,18 @@ static int __init alignment_init(void)
hook_fault_code(1, do_alignment, SIGBUS, BUS_ADRALN,
"alignment exception");
- hook_fault_code(3, do_alignment, SIGBUS, BUS_ADRALN,
- "alignment exception");
+
+ /*
+ * ARMv6K and ARMv7 use fault status 3 (0b00011) as Access Flag section
+ * fault, not as alignment error.
+ *
+ * TODO: handle ARMv6K properly. Runtime check for 'K' extension is
+ * needed.
+ */
+ if (cpu_architecture() <= CPU_ARCH_ARMv6) {
+ hook_fault_code(3, do_alignment, SIGBUS, BUS_ADRALN,
+ "alignment exception");
+ }
return 0;
}
diff --git a/arch/arm/mm/fault.c b/arch/arm/mm/fault.c
index 345a3c9..7e866e9 100644
--- a/arch/arm/mm/fault.c
+++ b/arch/arm/mm/fault.c
@@ -598,6 +598,17 @@ static int __init exceptions_init(void)
"I-cache maintenance fault");
}
+ if (cpu_architecture() >= CPU_ARCH_ARMv7) {
+ /*
+ * TODO: Access flag faults introduced in ARMv6K.
+ * Runtime check for 'K' extension is needed
+ */
+ hook_fault_code(3, do_bad, SIGSEGV, SEGV_MAPPERR,
+ "section access flag fault");
+ hook_fault_code(6, do_bad, SIGSEGV, SEGV_MAPPERR,
+ "section access flag fault");
+ }
+
return 0;
}
--
1.7.1.1
^ permalink raw reply related [flat|nested] 11+ messages in thread* [PATCH 4/5] ARMv6K and ARMv7 use fault statuses 3 and 6 as Access Flag fault
2010-07-19 8:53 ` [PATCH 4/5] ARMv6K and ARMv7 use fault statuses 3 and 6 as Access Flag fault Kirill A. Shutsemov
@ 2010-07-19 10:11 ` Sergei Shtylyov
2010-07-19 11:20 ` Kirill A. Shutemov
0 siblings, 1 reply; 11+ messages in thread
From: Sergei Shtylyov @ 2010-07-19 10:11 UTC (permalink / raw)
To: linux-arm-kernel
Hello.
Kirill A. Shutsemov wrote:
> Statuses 3 (0b00011) and 6 (0x00110) of DFSR are Access Flags faults on
> ARMv6K and ARMv7. Let's patch fsr_info[] at runtime if we are on ARMv7
> or later.
> Unfortunately, we don't have runtime check for 'K' extension, so we
> can't check for it.
> Signed-off-by: Kirill A. Shutemov <kirill@shutemov.name>
[...]
> diff --git a/arch/arm/mm/alignment.c b/arch/arm/mm/alignment.c
> index 77cfdbe..d073b64 100644
> --- a/arch/arm/mm/alignment.c
> +++ b/arch/arm/mm/alignment.c
> @@ -926,8 +926,18 @@ static int __init alignment_init(void)
>
> hook_fault_code(1, do_alignment, SIGBUS, BUS_ADRALN,
> "alignment exception");
> - hook_fault_code(3, do_alignment, SIGBUS, BUS_ADRALN,
> - "alignment exception");
> +
> + /*
> + * ARMv6K and ARMv7 use fault status 3 (0b00011) as Access Flag section
> + * fault, not as alignment error.
> + *
> + * TODO: handle ARMv6K properly. Runtime check for 'K' extension is
> + * needed.
> + */
> + if (cpu_architecture() <= CPU_ARCH_ARMv6) {
> + hook_fault_code(3, do_alignment, SIGBUS, BUS_ADRALN,
> + "alignment exception");
> + }
Curly braces not neeed here. I assume you haven't run your patch thru
scripts/checkpatch.pl?
WBR, Sergei
^ permalink raw reply [flat|nested] 11+ messages in thread* [PATCH 4/5] ARMv6K and ARMv7 use fault statuses 3 and 6 as Access Flag fault
2010-07-19 10:11 ` Sergei Shtylyov
@ 2010-07-19 11:20 ` Kirill A. Shutemov
2010-07-19 13:51 ` Sergei Shtylyov
0 siblings, 1 reply; 11+ messages in thread
From: Kirill A. Shutemov @ 2010-07-19 11:20 UTC (permalink / raw)
To: linux-arm-kernel
On Mon, Jul 19, 2010 at 02:11:32PM +0400, Sergei Shtylyov wrote:
> Hello.
>
> Kirill A. Shutsemov wrote:
>
> > Statuses 3 (0b00011) and 6 (0x00110) of DFSR are Access Flags faults on
> > ARMv6K and ARMv7. Let's patch fsr_info[] at runtime if we are on ARMv7
> > or later.
>
> > Unfortunately, we don't have runtime check for 'K' extension, so we
> > can't check for it.
>
> > Signed-off-by: Kirill A. Shutemov <kirill@shutemov.name>
> [...]
> > diff --git a/arch/arm/mm/alignment.c b/arch/arm/mm/alignment.c
> > index 77cfdbe..d073b64 100644
> > --- a/arch/arm/mm/alignment.c
> > +++ b/arch/arm/mm/alignment.c
> > @@ -926,8 +926,18 @@ static int __init alignment_init(void)
> >
> > hook_fault_code(1, do_alignment, SIGBUS, BUS_ADRALN,
> > "alignment exception");
> > - hook_fault_code(3, do_alignment, SIGBUS, BUS_ADRALN,
> > - "alignment exception");
> > +
> > + /*
> > + * ARMv6K and ARMv7 use fault status 3 (0b00011) as Access Flag section
> > + * fault, not as alignment error.
> > + *
> > + * TODO: handle ARMv6K properly. Runtime check for 'K' extension is
> > + * needed.
> > + */
> > + if (cpu_architecture() <= CPU_ARCH_ARMv6) {
> > + hook_fault_code(3, do_alignment, SIGBUS, BUS_ADRALN,
> > + "alignment exception");
> > + }
>
> Curly braces not neeed here. I assume you haven't run your patch thru
> scripts/checkpatch.pl?
total: 0 errors, 0 warnings, 37 lines checked
I'll remove it if you want. But I think it reasonable to leave braces in
cases like:
if (condition) {
do_this(a, very_long, list, of, parameters,
second, part, of, the, list);
}
What do you think?
--
Kirill A. Shutemov
^ permalink raw reply [flat|nested] 11+ messages in thread* [PATCH 4/5] ARMv6K and ARMv7 use fault statuses 3 and 6 as Access Flag fault
2010-07-19 11:20 ` Kirill A. Shutemov
@ 2010-07-19 13:51 ` Sergei Shtylyov
0 siblings, 0 replies; 11+ messages in thread
From: Sergei Shtylyov @ 2010-07-19 13:51 UTC (permalink / raw)
To: linux-arm-kernel
Kirill A. Shutemov wrote:
>> Hello.
>> Kirill A. Shutsemov wrote:
>>> Statuses 3 (0b00011) and 6 (0x00110) of DFSR are Access Flags faults on
>>> ARMv6K and ARMv7. Let's patch fsr_info[] at runtime if we are on ARMv7
>>> or later.
>>> Unfortunately, we don't have runtime check for 'K' extension, so we
>>> can't check for it.
>>> Signed-off-by: Kirill A. Shutemov <kirill@shutemov.name>
>> [...]
>>> diff --git a/arch/arm/mm/alignment.c b/arch/arm/mm/alignment.c
>>> index 77cfdbe..d073b64 100644
>>> --- a/arch/arm/mm/alignment.c
>>> +++ b/arch/arm/mm/alignment.c
>>> @@ -926,8 +926,18 @@ static int __init alignment_init(void)
>>>
>>> hook_fault_code(1, do_alignment, SIGBUS, BUS_ADRALN,
>>> "alignment exception");
>>> - hook_fault_code(3, do_alignment, SIGBUS, BUS_ADRALN,
>>> - "alignment exception");
>>> +
>>> + /*
>>> + * ARMv6K and ARMv7 use fault status 3 (0b00011) as Access Flag section
>>> + * fault, not as alignment error.
>>> + *
>>> + * TODO: handle ARMv6K properly. Runtime check for 'K' extension is
>>> + * needed.
>>> + */
>>> + if (cpu_architecture() <= CPU_ARCH_ARMv6) {
>>> + hook_fault_code(3, do_alignment, SIGBUS, BUS_ADRALN,
>>> + "alignment exception");
>>> + }
>> Curly braces not neeed here. I assume you haven't run your patch thru
>> scripts/checkpatch.pl?
> total: 0 errors, 0 warnings, 37 lines checked
Strange, it used to warn about superfluous braces...
> I'll remove it if you want. But I think it reasonable to leave braces in
> cases like:
> if (condition) {
> do_this(a, very_long, list, of, parameters,
> second, part, of, the, list);
> }
> What do you think?
I wouldn't use braces in this case. But it's up to you after all, if
checkpatch.pl is indifferent about them...
WBR, Sergei
^ permalink raw reply [flat|nested] 11+ messages in thread
* [PATCH 5/5] Workaround infinity loop in handling of translation faults
2010-07-19 8:53 [PATCH 0/5] ARM: fix exceptions handling Kirill A. Shutsemov
` (3 preceding siblings ...)
2010-07-19 8:53 ` [PATCH 4/5] ARMv6K and ARMv7 use fault statuses 3 and 6 as Access Flag fault Kirill A. Shutsemov
@ 2010-07-19 8:53 ` Kirill A. Shutsemov
4 siblings, 0 replies; 11+ messages in thread
From: Kirill A. Shutsemov @ 2010-07-19 8:53 UTC (permalink / raw)
To: linux-arm-kernel
From: Kirill A. Shutemov <kirill@shutemov.name>
On ARM one Linux PGD entry contains two hardware entries (see page
tables layout in pgtable.h). We normally guarantee that we always
fill both L1 entries. But create_mapping() doesn't follow the rule.
It can create inidividual L1 entries, so here we have to call
pmd_none() check in do_translation_fault() for the entry really
corresponded to address, not for the first of pair.
Signed-off-by: Kirill A. Shutemov <kirill@shutemov.name>
---
arch/arm/mm/fault.c | 11 ++++++++++-
1 files changed, 10 insertions(+), 1 deletions(-)
diff --git a/arch/arm/mm/fault.c b/arch/arm/mm/fault.c
index 7e866e9..f5f1190 100644
--- a/arch/arm/mm/fault.c
+++ b/arch/arm/mm/fault.c
@@ -413,7 +413,16 @@ do_translation_fault(unsigned long addr, unsigned int fsr,
pmd_k = pmd_offset(pgd_k, addr);
pmd = pmd_offset(pgd, addr);
- if (pmd_none(*pmd_k))
+ /*
+ * On ARM one Linux PGD entry contains two hardware entries (see page
+ * tables layout in pgtable.h). We normally guarantee that we always
+ * fill both L1 entries. But create_mapping() doesn't follow the rule.
+ * It can create inidividual L1 entries, so here we have to call
+ * pmd_none() check for the entry really corresponded to address, not
+ * for the first of pair.
+ */
+ index = (addr >> SECTION_SHIFT) & 1;
+ if (pmd_none(pmd_k[index]))
goto bad_area;
copy_pmd(pmd, pmd_k);
--
1.7.1.1
^ permalink raw reply related [flat|nested] 11+ messages in thread