[PATCHv3 8/8] powerpc/vdso: remove arch_vma_name
From: Dmitry Safonov <hidden>
Date: 2016-10-27 21:45:38
Also in:
linux-mm, lkml
Subsystem:
linux for powerpc (32-bit and 64-bit), the rest · Maintainers:
Madhavan Srinivasan, Michael Ellerman, Linus Torvalds
It's not needed since vdso is inserted with vm_special_mapping
which contains vma name.
This also reverts commit f2053f1a7bf6 ("powerpc/perf_counter: Fix vdso
detection") as not needed anymore.
See also commit f7b6eb3fa072 ("x86: Set context.vdso before installing
the mapping").
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <redacted>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: linuxppc-dev@lists.ozlabs.org
Cc: linux-mm@kvack.org
Signed-off-by: Dmitry Safonov <redacted>
---
arch/powerpc/kernel/vdso.c | 20 +++-----------------
1 file changed, 3 insertions(+), 17 deletions(-)
diff --git a/arch/powerpc/kernel/vdso.c b/arch/powerpc/kernel/vdso.c
index 431bdf7ec68e..f66f52aa94de 100644
--- a/arch/powerpc/kernel/vdso.c
+++ b/arch/powerpc/kernel/vdso.c@@ -208,13 +208,6 @@ static int map_vdso(struct vm_special_mapping *vsm, unsigned long vdso_pages, vdso_base = ALIGN(vdso_base, VDSO_ALIGNMENT); /* - * Put vDSO base into mm struct. We need to do this before calling - * install_special_mapping or the perf counter mmap tracking code - * will fail to recognise it as a vDSO (since arch_vma_name fails). - */ - current->mm->context.vdso_base = vdso_base; - - /* * our vma flags don't have VM_WRITE so by default, the process isn't * allowed to write those pages. * gdb can break that with ptrace interface, and thus trigger COW on
@@ -228,10 +221,10 @@ static int map_vdso(struct vm_special_mapping *vsm, unsigned long vdso_pages, VM_READ|VM_EXEC| VM_MAYREAD|VM_MAYWRITE|VM_MAYEXEC, vsm); - if (IS_ERR(vma)) { + if (IS_ERR(vma)) ret = PTR_ERR(vma); - current->mm->context.vdso_base = 0; - } + else + current->mm->context.vdso_base = vdso_base; out_up_mmap_sem: up_write(&mm->mmap_sem);
@@ -262,13 +255,6 @@ int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp) return -1; } -const char *arch_vma_name(struct vm_area_struct *vma) -{ - if (vma->vm_mm && vma->vm_start == vma->vm_mm->context.vdso_base) - return "[vdso]"; - return NULL; -} - #ifdef CONFIG_VDSO32 #include "vdso_common.c" #endif /* CONFIG_VDSO32 */
--
2.10.1