From: Andi Kleen <[email protected]>
Date: Tue, 24 Apr 2007 21:28:11 +0200
> On Tuesday 24 April 2007 08:03:03 Ashok Raj wrote:
> > PCI specs permit zero length reads (ZLR) even if the mapping for that region
> > is write only. Support for this feature is indicated by the presence of a bit
> > in the DMAR capability. If a particular DMAR does not support this capability
> > we map write-only regions as read-write.
> >
> > This option can also provides a workaround for some drivers that request
> > a write-only mapping when they really should request a read-write.
> > (We ran into one such case in eepro100.c in handling rx_ring_dma)
>
> Better just fix the drivers instead of adding such hacks
I totally agree.
It is a feature when we have a device which can enforce such
permissions correctly and thus trap such bad uses. If you
paper around it, these things will never get fixed.
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [email protected]
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
[Index of Archives]
[Kernel Newbies]
[Netfilter]
[Bugtraq]
[Photo]
[Stuff]
[Gimp]
[Yosemite News]
[MIPS Linux]
[ARM Linux]
[Linux Security]
[Linux RAID]
[Video 4 Linux]
[Linux for the blind]
[Linux Resources]
