Re: HPT374 detection crash with 74811f355f4f69a187fa74892dcf2a684b84ce99

[Sergei Shtylyov]

Hello, I just wrote:

> > Hi there, Looks like your commit 74811f355f4f69a187fa74892dcf2a684b84ce99
> >  (hpt366: convert to use ->host_priv)

>    Thanks for doing the bisection.

> > has caused the following crash:

>    Oops, we did it again. :-)

   Already seeing Bart's mistake, see below:

> > (Full dmesg follows, as captured from a serial console)

> > [   22.555200] hpt366: HPT374 chipset detected
> > [   22.559489] hpt366 0000:03:06.0: IDE controller (0x1103:0x0008 rev 0x07)
> > [   22.566278] HPT366_IDE 0000:03:06.0: PCI INT A -> GSI 28 (level, low) -> IRQ 28
> > [   22.573729] usb 1-2: new full speed USB device using uhci_hcd and address 4
> > [   22.580726] pci 0000:03:06.1: PCI INT A -> GSI 28 (level, low) -> IRQ 28
> > [   22.587529] hpt366 0000:03:06.0: DPLL base: 48 MHz, f_CNT: 142, assuming 33 MHz PCI
> > [   22.602705] hpt366 0000:03:06.0: using 50 MHz DPLL clock
> > [   22.608181] hpt366 0000:03:06.0: 100% native mode on irq 28
> > [   22.613831] hpt366 0000:03:06.1: no clock data saved by BIOS

>    Aha, HPT374 workaround for reading BIOS clock data didn't get executed.

> > [   22.731015] usb 1-2: configuration #1 chosen from 1 choice
> > [   22.737191] ata2.00: ATA-6: ST3120022A, 3.04, max UDMA/100
> > [   22.738880] hub 1-2:1.0: USB hub found
> > [   22.746597] ata2.00: 234441648 sectors, multi 16: LBA48
> > [   22.747804] hpt366 0000:03:06.1: DPLL base: 33 MHz, f_CNT: 139, assuming

>    Uh, I wonder where did it get those 33 MHz DPLL base -- there's 
> simply no such base.  Looks like memory addressed by .host_priv got 
> corrupt...

   No, that's just wrong pointer arithmetics there:

       struct hpt_info *info = host->host_priv + (hwif->dev == host->dev[1]);

The 'host_priv' is declared as 'void *', hence in case the condition abobe is 
true, there will be added only 1 to host->host_priv, not sizeof(struct 
hpt_info) as it should've been...

MBR, Sergei

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