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Subject[PATCH 0/4] x86,mm: vdso fixes for an OOPS and /proc/PID/maps
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[This applies to tip/x86/vdso.  Patch 1/4 is a resend.]

This fixes an OOPS on systems without an HPET and incomplete
information in /proc/PID/maps.

The latter is done by adding a new vm_ops callback to replace
arch_vma_name, which is inflexible and awkward to use correctly.

With this series applied, calling mremap on the vdso results in
sensible output in /proc/PID/maps and the vvar area shows up
correctly. I don't want to guarantee that mremap on the vdso will
do anything sensible right now, but that's unchanged from before.
In fact, I suspect that mremapping the vdso on 32-bit tasks is
rather broken right now due to sigreturn.

In current kernels, mremapping the vdso blows away the name:
badc0de0000-badc0de2000 r-xp 00000000 00:00 0

Now it doesn't:
badc0de0000-badc0de1000 r-xp 00000000 00:00 0 [vdso]

As a followup, it might pay to replace install_special_mapping with
a new install_vdso_mapping function that hardcodes the "[vdso]"
name, to separately fix all the other arch_vma_name users (maybe
just ARM?) and then kill arch_vma_name completely.

NB: This touches core mm code. I'd appreciate some review by the mm
folks.

Andy Lutomirski (4):
x86,vdso: Fix an OOPS accessing the hpet mapping w/o an hpet
mm,fs: Add vm_ops->name as an alternative to arch_vma_name
x86,mm: Improve _install_special_mapping and fix x86 vdso naming
x86,mm: Replace arch_vma_name with vm_ops->name for vsyscalls

arch/x86/include/asm/vdso.h | 6 ++-
arch/x86/mm/init_64.c | 20 +++++-----
arch/x86/vdso/vdso2c.h | 5 ++-
arch/x86/vdso/vdso32-setup.c | 7 ----
arch/x86/vdso/vma.c | 26 ++++++++-----
fs/binfmt_elf.c | 8 ++++
fs/proc/task_mmu.c | 6 +++
include/linux/mm.h | 10 ++++-
include/linux/mm_types.h | 6 +++
mm/mmap.c | 89 +++++++++++++++++++++++++++++---------------
10 files changed, 124 insertions(+), 59 deletions(-)

--
1.9.0



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