Date: Fri, 02 Nov 2007 13:57:57 +0300 From: Alexander Sabourenkov <screwdriver@lxnt.info> To: =?UTF-8?B?U8O4cmVuIFNjaG1pZHQ=?= <sos@deepcore.dk> Cc: freebsd-hackers@FreeBSD.ORG, sos@FreeBSD.ORG, freebsd-current@FreeBSD.ORG, "Matthew D. Fuller" <fullermd@over-yonder.net>, Thierry Herbelot <thierry@herbelot.com> Subject: Re: Patch RFC: Promise SATA300 TX4 hardware bug workaround. Message-ID: <472B02B5.9020502@lxnt.info> In-Reply-To: <472AFEC3.7090001@deepcore.dk> References: <472A548B.50406@lxnt.info> <472AFB75.1070207@deepcore.dk> <472AFEC3.7090001@deepcore.dk>
next in thread | previous in thread | raw e-mail | index | archive | help
Søren Schmidt wrote: > Søren Schmidt wrote: >> Good catch! >> >> However from my quick glimpse at the Promise sources the limit seems >> to be 32 Dwords ie 32*4 = 128bytes. Please see driver named 4_sataii150-300_linux2.6-src_x86-64_v1.01.0.23 >> I'll investigate further and ask Promise for the gory details, stay >> tuned... >> I dont think the PRD count limitation is a real problem, I've newer >> seen that long a list and IIRC we newer do more than 64K transfers in >> one go (yet). In (current) practice, yes, but check should be there even if only to document the limit. >> Anyhow I need to get checks in for that not just here... >> >> Give me a few days and I'll get this figured out for 7-rel... > Oh, and I forgot, do you have a surefire way to reproduce the problem so > the fix can be tested ? dd if=/dev/ad8 of=/dev/null bs=1048576 count=1000 works every time. I have tested it on my home machine: without the patch first timeouts and errors appear about 10 seconds into the read. with the patch a read of entire disk (320G) completed without errors. Previous tests of analogous linux driver fix shown no errors and no data corruption on two write-whole-drive, read-whole-drive cycles. > > I've newer been able to trigger this problem myself so far. > Seems like the bug is highly configuration-dependent, or pci-chiset-depended, or just present in some production runs and not other. -- ./lxnt
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?472B02B5.9020502>