CVS commit: [netbsd-5] src/sys/dev/ic

["Manuel Bouyer" <bouyer%netbsd.org@localhost>]

Module Name:    src
Committed By:   bouyer
Date:           Sun Jan 16 13:06:49 UTC 2011

Modified Files:
        src/sys/dev/ic [netbsd-5]: ahcisata_core.c

Log Message:
Pull up following revision(s) (requested by tsutsui in ticket #1530):
        sys/dev/ic/ahcisata_core.c: revision 1.31
Don't call bus_dmamap_load(9) and bus_dmamap_sync(9) on command xfers
if (AT_READ|AT_WRITE) in ata_c->flags is set but ata_c->bcount is zero.
Someone actually tries to put such a command and it causes
DIAGNOSTIC panic in x86/bus_dma.c:_bus_dmamap_sync().
I think bus_dma(9) API itself may allow calls with mapsize==0
but there are many MD code that asserts offset>=mapsize or len==0.
The problem is reported and fix is confirmed by Takuro KUBOTA
with XEN DOM0 kernel (which has options DIAGNOSTIC).


To generate a diff of this commit:
cvs rdiff -u -r1.18.4.4 -r1.18.4.5 src/sys/dev/ic/ahcisata_core.c

Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.