Re: [Qemu-devel] [PATCH_v2] ahci.c: mask unused flags when reading size PRDT DBC

[Kevin Wolf]

Am 01.07.2014 um 13:13 hat address@hidden geschrieben:
> From: Reza Jelveh <address@hidden>
> 
> The data byte count(DBC) read from the description information is defined for
> bits 21:00. Bits 30:22 are reserved and bit 31 is the Interrupt on Completion
> (I) flag.
> 
> Completion interrupts are triggered after every transaction instead of on
> I-flag in QEMU. tbl_entry_size is a signed integer and improperly reading the
> DBC leads to a negative offset that causes sglist allocation to fail.
> 
> Signed-off-by: Reza Jelveh <address@hidden>
> ---
> This requires a custom ovmf image with sata controller for testing:
> 
> http://reza.jelveh.me/assets/OVMF.fd.bz2
> 
> Signed-off-by: Reza Jelveh <address@hidden>

Reviewed-by: Kevin Wolf <address@hidden>

The spec also seems to require an even byte count, which we don't seem
to check. Do we want to add this? (In a separate patch, of course.)

We'll also want a qtest case to verify the fix and for regression
testing. John?

And finally, please don't forget to CC the block maintainers (Stefan and
me) for any AHCI patches.

Kevin