On Thu, Sep 09, 2010 at 05:00:46PM +0200, Tejun Heo wrote: > (cc's added) > Hello, > > On 09/08/2010 08:26 PM, gianluca wrote: > > Today I tried the kernel 2.6.35 in one of my boxes but I realized that the > > box doesn't detect my SATA HD anymore. The logs show that the driver sata_sil > > is correctly loaded. With 2.6.34 it worked fine. > > > > So I tried to test the latest git to see if the issue was fixed, but that > > kernel exhibits the same behaviour. Then I looked at the linux-ide mailing list > > archives at http://marc.info/?t=128232284600001&r=1&w=2 and I found out that > > the issue is known but not solved and since I could reliably reproduce the > > problen I started to bisect. > > > > The logs of the bisection are attached. It pointed to the commit > > 978c066691a49a205673672a55685305663a2554 ( libata: Remove excess delay in the > > tf_load path ). > > > > So I reverted that commit and got a bootable kernel again. I think this commit > > exposed a timing bug in the sata_sil driver. > > I love you. Thank you so much for bisecting it. :-) > > Can you please test whether the patch at the end of this message is > enough to fix the problem? I just tested the patch you attached on a vanilla 2.6.35.4 kernel and it works for me: the disk is there again. Thank you! gianluca > > Alan, the above commit seems a bit dangerous as writes can be merged. > Also, ISTR delay requirements for PATA while loading registers. Mark, > Sergei, what do you guys think? > > diff --git a/drivers/ata/libata-sff.c b/drivers/ata/libata-sff.c > index 030b1c4..6a43129 100644 > --- a/drivers/ata/libata-sff.c > +++ b/drivers/ata/libata-sff.c > @@ -418,6 +418,7 @@ void ata_sff_tf_load(struct ata_port *ap, const struct ata_taskfile *tf) > if (ioaddr->ctl_addr) > iowrite8(tf->ctl, ioaddr->ctl_addr); > ap->last_ctl = tf->ctl; > + ap->ops->sff_check_status(ap); > } > > if (is_addr && (tf->flags & ATA_TFLAG_LBA48)) { > @@ -453,6 +454,7 @@ void ata_sff_tf_load(struct ata_port *ap, const struct ata_taskfile *tf) > iowrite8(tf->device, ioaddr->device_addr); > VPRINTK("device 0x%X\n", tf->device); > } > + ap->ops->sff_check_status(ap); > } > EXPORT_SYMBOL_GPL(ata_sff_tf_load); -- To unsubscribe from this list: send the line "unsubscribe linux-ide" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
