From mboxrd@z Thu Jan 1 00:00:00 1970 From: Nathan_Lynch@mentor.com (Nathan Lynch) Date: Mon, 4 Aug 2014 08:12:26 -0500 Subject: [PATCH v8 01/10] ARM: use _install_special_mapping for sigpage In-Reply-To: <20140804124630.GG15117@arm.com> References: <1407003407-31219-1-git-send-email-nathan_lynch@mentor.com> <1407003407-31219-2-git-send-email-nathan_lynch@mentor.com> <20140804124630.GG15117@arm.com> Message-ID: <53DF86BA.2030207@mentor.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On 08/04/2014 07:46 AM, Will Deacon wrote: > On Sat, Aug 02, 2014 at 07:16:38PM +0100, Nathan Lynch wrote: >> _install_special_mapping allows the VMA to be identifed in >> /proc/pid/maps without the use of arch_vma_name, providing a >> slight net reduction in object size: >> >> text data bss dec hex filename >> 2996 96 144 3236 ca4 arch/arm/kernel/process.o (before) >> 2956 104 144 3204 c84 arch/arm/kernel/process.o (after) >> >> Signed-off-by: Nathan Lynch >> Reviewed-by: Kees Cook >> --- >> arch/arm/kernel/process.c | 24 ++++++++++++++++-------- >> 1 file changed, 16 insertions(+), 8 deletions(-) >> >> diff --git a/arch/arm/kernel/process.c b/arch/arm/kernel/process.c >> index 81ef686a91ca..46fbbb3701a0 100644 >> --- a/arch/arm/kernel/process.c >> +++ b/arch/arm/kernel/process.c >> @@ -472,19 +472,23 @@ int in_gate_area_no_mm(unsigned long addr) >> >> const char *arch_vma_name(struct vm_area_struct *vma) >> { >> - return is_gate_vma(vma) ? "[vectors]" : >> - (vma->vm_mm && vma->vm_start == vma->vm_mm->context.sigpage) ? >> - "[sigpage]" : NULL; >> + return is_gate_vma(vma) ? "[vectors]" : NULL; >> } > > Why do you need this function? I just removed it for arm64 and I think x86 > has done the same. I think arch_vma_name is still needed for arm as long as the vectors page is not installed using _install_special_mapping. I'm honestly not sure whether moving the vectors page to that API would be appropriate, but it would be a larger undertaking.