On Mon, 2008-10-13 at 17:03 -0700, H. Peter Anvin wrote: > I just tried a top of tree i386 kernel under KVM, and found that it > fails to boot with a hang during initialization, right after: > > console [netcon0] enabled > > netconsole: network logging started > > Uniform Multi-Platform E-IDE driver > > ide-floppy driver 1.00 > > Driver 'sd' needs updating - please use bus_type methods > > scsi0 : ata_piix > > scsi1 : ata_piix > > ata1: PATA max MWDMA2 cmd 0x1f0 ctl 0x3f6 bmdma 0xc000 irq 14 > > ata2: PATA max MWDMA2 cmd 0x170 ctl 0x376 bmdma 0xc008 irq 15 > > ata1.00: ATA-7: QEMU HARDDISK, 0.9.1, max UDMA/100 > > ata1.00: 16777216 sectors, multi 16: LBA48 > > ata1.00: configured for MWDMA2 > > ata2.00: ATAPI: QEMU DVD-ROM, 0.9.1, max UDMA/100 > > ata2.00: configured for MWDMA2 > > scsi 0:0:0:0: Direct-Access ATA QEMU HARDDISK 0.9. PQ: 0 > ANSI: 5 > > Bisection fingered the following commit: > > 7404ad3b6d04efbd918e9e2e776bf560fbedf47d is first bad commit > > commit 7404ad3b6d04efbd918e9e2e776bf560fbedf47d > > Author: James Bottomley <James.Bottomley@xxxxxxxxxxxxxxxxxxxxx> > > Date: Sun Aug 31 10:41:52 2008 -0500 > > > [SCSI] sd: use generic helper to print capacities in both binary > and SI > > Signed-off-by: James Bottomley > <James.Bottomley@xxxxxxxxxxxxxxxxxxxxx> > > :040000 040000 98fc7ae95211b8d16e2e8ca46997be660ad9ba93 > 2d35d0a2b6232411b840a9ccf6a52b946172566e M drivers > > However, simply reverting this commit caused a panic on boot (not > entirely surprising.) Actually, it is surprising. That patch takes the default arithmetic for calculating the disk size out of sd and uses a routine to do it more efficiently in lib/string_helpers.c So there are two problems: Why does it panic on revert (could you post the oops) and what does kvm object to in string_get_size ... it's a fairly innocuous routine as I read it ... your symptoms sound like the for loop isn't terminating. James -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
