Re: [Qemu-devel] [PATCH v3] migration/postcopy: use mis->bh instead of allocating a QEMUBH

[Wei Yang]

On Wed, Aug 07, 2019 at 07:35:34PM +0100, Dr. David Alan Gilbert wrote:
>* Wei Yang (address@hidden) wrote:
>> For migration incoming side, it either quit in precopy or postcopy. It
>> is safe to use the mis->bh for both instead of allocating a dedicated
>> QEMUBH for postcopy.
>> 
>> Signed-off-by: Wei Yang <address@hidden>
>> Reviewed-by: Dr. David Alan Gilbert <address@hidden>
>
>Hi Wei,
>  Can you check this, the patchew tests came back with a failure which
>seems bh related; I've not tried it, but can you just see if you can
>reproduce it?

Hmm... the error message in mail is a little confusion.

I see following error, but have no idea about what it is.

==8174==ERROR: AddressSanitizer: heap-use-after-free on address 0x61200002c7f0 
at pc 0x5566916cbf76 bp 0x7fc74f4b8680 sp 0x7fc74f4b8678
WRITE of size 1 at 0x61200002c7f0 thread T9
==8179==WARNING: ASan doesn't fully support makecontext/swapcontext functions 
and may produce false positives in some cases!
PASS 3 ahci-test /x86_64/ahci/pci_enable
==8192==WARNING: ASan doesn't fully support makecontext/swapcontext functions 
and may produce false positives in some cases!
    #0 0x5566916cbf75 in aio_notify /tmp/qemu-test/src/util/async.c:351:9
    #1 0x5566916cdbab in qemu_bh_schedule /tmp/qemu-test/src/util/async.c:167:9
    #2 0x5566916d0db0 in aio_co_schedule /tmp/qemu-test/src/util/async.c:464:5
---
  Right alloca redzone:    cb
  Shadow gap:              cc
==8174==ABORTING
ERROR - too few tests run (expected 40, got 18)
make: *** [/tmp/qemu-test/src/tests/Makefile.include:904: check-unit] Error 1
make: *** Waiting for unfinished jobs....
PASS 4 ahci-test /x86_64/ahci/hba_spec

I am trying to reproduce it. I guess docker should be used. Would you mind
sharing some link on setup the environment.

Thanks

-- 
Wei Yang
Help you, Help me