[PATCH v2 0/7] /proc/kcore improvements

[Omar Sandoval <osandov@osandov.com>]

From: Omar Sandoval <osandov@fb.com>

Hi,

This series makes a few improvements to /proc/kcore. Patches 1 and 2 are
prep patches. Patch 3 is a fix/cleanup. Patch 4 is another prep patch.
Patches 5 and 6 are optimizations to ->read(). Patch 7 adds vmcoreinfo
to /proc/kcore (apparently I'm not the only one who wants this, see
https://www.spinics.net/lists/arm-kernel/msg665103.html).

I tested that the crash utility still works with this applied, and
readelf is happy with it, as well.

Andrew, since this didn't get any traction on the fsdevel side, and
you're already carrying James' patch, could you take this through -mm?

Thanks!

Changes from v1:

- Rebased onto v4.18-rc4 + James' patch
  (https://patchwork.kernel.org/patch/10519739/) in the mm tree
- Fix spurious sparse warning (see the report and response in
  https://patchwork.kernel.org/patch/10512431/)

Omar Sandoval (7):
  proc/kcore: don't grab lock for kclist_add()
  proc/kcore: replace kclist_lock rwlock with rwsem
  proc/kcore: fix memory hotplug vs multiple opens race
  proc/kcore: hold lock during read
  proc/kcore: clean up ELF header generation
  proc/kcore: optimize multiple page reads
  proc/kcore: add vmcoreinfo note to /proc/kcore

 fs/proc/Kconfig            |   1 +
 fs/proc/kcore.c            | 536 +++++++++++++++++--------------------
 include/linux/crash_core.h |   2 +
 kernel/crash_core.c        |   4 +-
 4 files changed, 251 insertions(+), 292 deletions(-)

-- 
2.18.0