linux/arch/x86/vdso
Roland McGrath 5de253cc5b x86 vDSO: don't map 32-bit vdso when disabled
We map a VMA for the 32-bit vDSO even when it's disabled, which is stupid.
For the 32-bit kernel it's the vdso_enabled boot parameter/sysctl
and for the 64-bit kernel it's the vdso32 boot parameter/syscall32 sysctl.

When it's disabled, we don't pass AT_SYSINFO_EHDR so processes don't use
the vDSO for anything, but we still map it.  For the non-compat vDSO,
this means we're always putting an extra VMA somewhere, maybe lousing
up the control of the address space the user was hoping for.

Honor the setting by doing nothing in arch_setup_additional_pages.

[ also see: "x86 vDSO: don't use disabled vDSO for signal trampoline" ]

Signed-off-by: Roland McGrath <roland@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-04-17 17:40:45 +02:00
..
vdso32 x86: gitignore arch/x86/vdso files 2008-01-30 13:32:32 +01:00
.gitignore x86: add vdso32-int80-syms.lds to .gitignore 2008-01-30 13:33:24 +01:00
Makefile x86 vdso: fix build locale dependency 2008-02-29 18:55:39 +01:00
vclock_gettime.c x86: remove duplicate includes 2008-01-30 13:30:32 +01:00
vdso32-setup.c x86 vDSO: don't map 32-bit vdso when disabled 2008-04-17 17:40:45 +02:00
vdso32.S x86 vDSO: consolidate vdso32 2008-01-30 13:30:43 +01:00
vdso-layout.lds.S x86 vDSO: new layout 2008-01-30 13:30:41 +01:00
vdso-note.S x86_64: move vdso 2007-10-11 11:17:10 +02:00
vdso.lds.S x86 vDSO: new layout 2008-01-30 13:30:41 +01:00
vdso.S x86_64: move vdso 2007-10-11 11:17:10 +02:00
vextern.h x86_64: move vdso 2007-10-11 11:17:10 +02:00
vgetcpu.c x86: introduce native_read_tscp 2008-01-30 13:31:06 +01:00
vma.c x86 vDSO: use vdso-syms.lds 2008-01-30 13:30:41 +01:00
vvar.c x86: vdso put vars in rodata 2007-10-17 20:16:43 +02:00