Re: [PATCH v3 2/6] Disable instrumentation for some code

Re: [PATCH v3 2/6] Disable instrumentation for some code

[Liuwenliang (Abbott Liu)]

On Tue, Apr 03, 2018 at 19:39, Russell King - ARM Linux:
>On Tue, Apr 03, 2018 at 12:30:42PM +0100, Marc Zyngier wrote:
>> On 02/04/18 13:04, Abbott Liu wrote:
>> > From: Andrey Ryabinin <a.ryabinin@samsung.com>
>> > 
>> > Disable instrumentation for arch/arm/boot/compressed/*
>> > ,arch/arm/kvm/hyp/* and arch/arm/vdso/* because those
>> > code won't linkd with kernel image.
>> > 
>> > Disable kasan check in the function unwind_pop_register
>> > because it doesn't matter that kasan checks failed when
>> > unwind_pop_register read stack memory of task.
>> > 
>> > Reviewed-by: Russell King - ARM Linux <linux@armlinux.org.uk>
>> > Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
>> > Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
>> 
>> Just because I replied to this patch doesn't mean you can stick my
>> Reviewed-by tag on it. Please drop this tag until I explicitly say that
>> you can add it (see Documentation/process/submitting-patches.rst,
>> section 11).
>> 
>> Same goes for patch 1.
>
>Same goes for that reviewed-by line for me.  From my records, I never
>even looked at patch 2 from the first posting, and I don't appear to
>have the second posting in my mailbox (it's probably been classed as
>spam by dspam.)  So these reviewed-by lines seem to be totally
>misleading.

Thank Marc Zyngier and Russell King.
I have read Documentation/process/submitting-patches.rst and understand
it now. I will change it in the next version.

Re: [PATCH v3 2/6] Disable instrumentation for some code

[Russell King - ARM Linux]

On Tue, Apr 03, 2018 at 12:30:42PM +0100, Marc Zyngier wrote:
> On 02/04/18 13:04, Abbott Liu wrote:
> > From: Andrey Ryabinin <a.ryabinin@samsung.com>
> > 
> > Disable instrumentation for arch/arm/boot/compressed/*
> > ,arch/arm/kvm/hyp/* and arch/arm/vdso/* because those
> > code won't linkd with kernel image.
> > 
> > Disable kasan check in the function unwind_pop_register
> > because it doesn't matter that kasan checks failed when
> > unwind_pop_register read stack memory of task.
> > 
> > Reviewed-by: Russell King - ARM Linux <linux@armlinux.org.uk>
> > Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
> > Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
> 
> Just because I replied to this patch doesn't mean you can stick my
> Reviewed-by tag on it. Please drop this tag until I explicitly say that
> you can add it (see Documentation/process/submitting-patches.rst,
> section 11).
> 
> Same goes for patch 1.

Same goes for that reviewed-by line for me.  From my records, I never
even looked at patch 2 from the first posting, and I don't appear to
have the second posting in my mailbox (it's probably been classed as
spam by dspam.)  So these reviewed-by lines seem to be totally
misleading.

-- 
RMK's Patch system: http://www.armlinux.org.uk/developer/patches/
FTTC broadband for 0.8mile line in suburbia: sync at 8.8Mbps down 630kbps up
According to speedtest.net: 8.21Mbps down 510kbps up

Re: [PATCH v3 2/6] Disable instrumentation for some code

[Marc Zyngier]

On 02/04/18 13:04, Abbott Liu wrote:
> From: Andrey Ryabinin <a.ryabinin@samsung.com>
> 
> Disable instrumentation for arch/arm/boot/compressed/*
> ,arch/arm/kvm/hyp/* and arch/arm/vdso/* because those
> code won't linkd with kernel image.
> 
> Disable kasan check in the function unwind_pop_register
> because it doesn't matter that kasan checks failed when
> unwind_pop_register read stack memory of task.
> 
> Reviewed-by: Russell King - ARM Linux <linux@armlinux.org.uk>
> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
> Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>

Just because I replied to this patch doesn't mean you can stick my
Reviewed-by tag on it. Please drop this tag until I explicitly say that
you can add it (see Documentation/process/submitting-patches.rst,
section 11).

Same goes for patch 1.

Thanks,

	M.
-- 
Jazz is not dead. It just smells funny...

[PATCH v3 2/6] Disable instrumentation for some code

[Abbott Liu]

From: Andrey Ryabinin <a.ryabinin@samsung.com>

Disable instrumentation for arch/arm/boot/compressed/*
,arch/arm/kvm/hyp/* and arch/arm/vdso/* because those
code won't linkd with kernel image.

Disable kasan check in the function unwind_pop_register
because it doesn't matter that kasan checks failed when
unwind_pop_register read stack memory of task.

Reviewed-by: Russell King - ARM Linux <linux@armlinux.org.uk>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Tested-by: Joel Stanley <joel@jms.id.au>
Tested-by: Florian Fainelli <f.fainelli@gmail.com>
Tested-by: Abbott Liu <liuwenliang@huawei.com>
Signed-off-by: Abbott Liu <liuwenliang@huawei.com>
---
 arch/arm/boot/compressed/Makefile | 1 +
 arch/arm/kernel/unwind.c          | 3 ++-
 arch/arm/kvm/hyp/Makefile         | 4 ++++
 arch/arm/vdso/Makefile            | 2 ++
 4 files changed, 9 insertions(+), 1 deletion(-)

diff --git a/arch/arm/boot/compressed/Makefile b/arch/arm/boot/compressed/Makefile
index 45a6b9b..966103e 100644
--- a/arch/arm/boot/compressed/Makefile
+++ b/arch/arm/boot/compressed/Makefile
@@ -24,6 +24,7 @@ OBJS		+= hyp-stub.o
 endif
 
 GCOV_PROFILE		:= n
+KASAN_SANITIZE		:= n
 
 #
 # Architecture dependencies
diff --git a/arch/arm/kernel/unwind.c b/arch/arm/kernel/unwind.c
index 0bee233..2e55c7d 100644
--- a/arch/arm/kernel/unwind.c
+++ b/arch/arm/kernel/unwind.c
@@ -249,7 +249,8 @@ static int unwind_pop_register(struct unwind_ctrl_block *ctrl,
 		if (*vsp >= (unsigned long *)ctrl->sp_high)
 			return -URC_FAILURE;
 
-	ctrl->vrs[reg] = *(*vsp)++;
+	ctrl->vrs[reg] = READ_ONCE_NOCHECK(*(*vsp));
+	(*vsp)++;
 	return URC_OK;
 }
 
diff --git a/arch/arm/kvm/hyp/Makefile b/arch/arm/kvm/hyp/Makefile
index 63d6b40..0a8b500 100644
--- a/arch/arm/kvm/hyp/Makefile
+++ b/arch/arm/kvm/hyp/Makefile
@@ -24,3 +24,7 @@ obj-$(CONFIG_KVM_ARM_HOST) += hyp-entry.o
 obj-$(CONFIG_KVM_ARM_HOST) += switch.o
 CFLAGS_switch.o		   += $(CFLAGS_ARMV7VE)
 obj-$(CONFIG_KVM_ARM_HOST) += s2-setup.o
+
+GCOV_PROFILE	:= n
+KASAN_SANITIZE	:= n
+UBSAN_SANITIZE	:= n
diff --git a/arch/arm/vdso/Makefile b/arch/arm/vdso/Makefile
index bb411821..87abbb7 100644
--- a/arch/arm/vdso/Makefile
+++ b/arch/arm/vdso/Makefile
@@ -30,6 +30,8 @@ CFLAGS_vgettimeofday.o = -O2
 # Disable gcov profiling for VDSO code
 GCOV_PROFILE := n
 
+KASAN_SANITIZE := n
+
 # Force dependency
 $(obj)/vdso.o : $(obj)/vdso.so
 
-- 
2.9.0