diff options
| author | Anton Blanchard | 2009-09-21 16:57:40 +0000 |
|---|---|---|
| committer | Benjamin Herrenschmidt | 2009-09-24 15:31:45 +1000 |
| commit | f2053f1a7bf6005b4e81826b1ac8d0b4117c4cf0 (patch) | |
| tree | d8c69b5ead3bfb5b09d05dd4804ce022cdea8883 /arch/powerpc | |
| parent | 8bbde7a7062facf8af35bcc9a64cbafe8f36f3cf (diff) | |
powerpc/perf_counter: Fix vdso detection
perf_counter uses arch_vma_name() to detect a vdso region which in turn uses
current->mm->context.vdso_base. We need to initialise this before doing
the mmap or else we fail to detect the vdso.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Diffstat (limited to 'arch/powerpc')
| -rw-r--r-- | arch/powerpc/kernel/vdso.c | 14 |
1 files changed, 10 insertions, 4 deletions
diff --git a/arch/powerpc/kernel/vdso.c b/arch/powerpc/kernel/vdso.c index 3faaf29bdb29..94e2df3cae07 100644 --- a/arch/powerpc/kernel/vdso.c +++ b/arch/powerpc/kernel/vdso.c @@ -241,6 +241,13 @@ int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp) } /* + * 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 @@ -260,11 +267,10 @@ int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp) VM_MAYREAD|VM_MAYWRITE|VM_MAYEXEC| VM_ALWAYSDUMP, vdso_pagelist); - if (rc) + if (rc) { + current->mm->context.vdso_base = 0; goto fail_mmapsem; - - /* Put vDSO base into mm struct */ - current->mm->context.vdso_base = vdso_base; + } up_write(&mm->mmap_sem); return 0; |