Morally, the question of whether an address lies in a gate vma should be asked with respect to an mm, not a particular task.
Practically, dropping the dependency on task_struct will help make current and future operations on mm's more flexible and convenient. In particular, it allows some code paths to avoid the need to hold task_lock. The only architecture this change impacts in any significant way is x86_64. The principle change on that architecture is to mirror TIF_IA32 via a new flag in mm_context_t. This is the first of a two part series that implements safe writes to /proc/pid/mem. I will be posting the second series to lkml shortly. These patches are based on v2.6.38-rc8. The general approach used here was suggested to me by Alexander Viro, but any mistakes present in these patches are entirely my own. -- steve Stephen Wilson (5): x86: add context tag to mark mm when running a task in 32-bit compatibility mode x86: mark associated mm when running a task in 32 bit compatibility mode mm: arch: make get_gate_vma take an mm_struct instead of a task_struct mm: arch: make in_gate_area take an mm_struct instead of a task_struct mm: arch: rename in_gate_area_no_task to in_gate_area_no_mm arch/powerpc/kernel/vdso.c | 6 +++--- arch/s390/kernel/vdso.c | 6 +++--- arch/sh/kernel/vsyscall/vsyscall.c | 6 +++--- arch/x86/ia32/ia32_aout.c | 1 + arch/x86/include/asm/mmu.h | 6 ++++++ arch/x86/kernel/process_64.c | 8 ++++++++ arch/x86/mm/init_64.c | 16 ++++++++-------- arch/x86/vdso/vdso32-setup.c | 15 ++++++++------- fs/binfmt_elf.c | 2 +- fs/proc/task_mmu.c | 8 +++++--- include/linux/mm.h | 10 +++++----- kernel/kallsyms.c | 4 ++-- mm/memory.c | 8 ++++---- mm/mlock.c | 4 ++-- mm/nommu.c | 2 +- 15 files changed, 61 insertions(+), 42 deletions(-) _______________________________________________ Linuxppc-dev mailing list Linuxppc-dev@lists.ozlabs.org https://lists.ozlabs.org/listinfo/linuxppc-dev