Re: mmotm 2013-01-11-15-47 (trouble starting kvm)

On Sat, 12 Jan 2013, Zlatko Calusic wrote:

quoted

A git tree which contains the memory management portion of this tree is
maintained at git://git.kernel.org/pub/scm/linux/kernel/git/mhocko/mm.git
by Michal Hocko.  It contains the patches which are between the

The last commit I see in this tree is:

commit a0d271cbfed1dd50278c6b06bead3d00ba0a88f9
Author: Linus Torvalds [off-list ref]
Date:   Sun Sep 30 16:47:46 2012 -0700

    Linux 3.6

Is it dead? Or am I doing something wrong?

quoted

A full copy of the full kernel tree with the linux-next and mmotm patches
already applied is available through git within an hour of the mmotm
release.  Individual mmotm releases are tagged.  The master branch always
points to the latest release, so it's constantly rebasing.

http://git.cmpxchg.org/?p=linux-mmotm.git;a=summary

This mmotm tree contains the following patches against 3.8-rc3:
(patches marked "*" will be included in linux-next)

* lockdep-rwsem-provide-down_write_nest_lock.patch
* mm-mmap-annotate-vm_lock_anon_vma-locking-properly-for-lockdep.patch

Had to revert the above two patches to start KVM (win7) successfully.
Otherwise it would livelock on some semaphore, it seems. Couldn't kill it, ps
output would stuck, even reboot didn't work (had to use SysRQ).

Copy/pasting from my response to the other thread at 
https://lkml.org/lkml/2013/1/15/440


====
Thorough and careful review and analysis revealed that the rootcause very 
likely is that I am a complete nitwit.

Could you please try the patch below and report backt? Thanks.



From: Jiri Kosina <redacted>
Subject: [PATCH] lockdep, rwsem: fix down_write_nest_lock() if !CONFIG_DEBUG_LOCK_ALLOC

Commit 1b963c81b1 ("lockdep, rwsem: provide down_write_nest_lock()") 
contains a bug in a codepath when CONFIG_DEBUG_LOCK_ALLOC is disabled, 
which causes down_read() to be called instead of down_write() by mistake 
on such configurations. Fix that.

Signed-off-by: Jiri Kosina <redacted>
---
 include/linux/rwsem.h |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/include/linux/rwsem.h b/include/linux/rwsem.h
index 413cc11..8da67d6 100644
--- a/include/linux/rwsem.h
+++ b/include/linux/rwsem.h

@@ -135,7 +135,7 @@ do {								\
 
 #else
 # define down_read_nested(sem, subclass)		down_read(sem)
-# define down_write_nest_lock(sem, nest_lock)	down_read(sem)
+# define down_write_nest_lock(sem, nest_lock)	down_write(sem)
 # define down_write_nested(sem, subclass)	down_write(sem)
 #endif
 

-- 
Jiri Kosina
SUSE Labs

--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@kvack.org.  For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>