Re: [PATCH] x86_64: fix problems due to use of "outb" to port 80 on some AMD64x2 laptops, etc.

On 14-12-07 19:02, H. Peter Anvin wrote:

I believe this will suffer from the issue that was raised: this will use

udelay() long before loop calibration (and no, we can't just "be conservative" since there is no "conservative" value we can use.)

Worse, I suspect that at least the PIT, which may need to be used for udelay calibration, is one of the devices that may be affected. I have seen the Verilog for a contemporary chipset, and it can only access the PIT once per microsecond -- this actually has to do with the definition of the PIT; some of the PIT operations are ill-defined if allowed at a higher frequency than the PIT clock.

Was reported before indeed:

http://linux.derkeiler.com/Mailing-Lists/Kernel/2003-09/5764.html

Rene.

--
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/

---

• References:
  • [PATCH] x86_64: fix problems due to use of "outb" to port 80 on some AMD64x2 laptops, etc.
    • From: "David P. Reed" <[email protected]>
  • Re: [PATCH] x86_64: fix problems due to use of "outb" to port 80 on some AMD64x2 laptops, etc.
    • From: Ingo Molnar <[email protected]>
  • Re: [PATCH] x86_64: fix problems due to use of "outb" to port 80 on some AMD64x2 laptops, etc.
    • From: "H. Peter Anvin" <[email protected]>

• Prev by Date: Re: [PATCH 3/3] net: wireless: bcm43xx: big_buffer_sem semaphore to mutex
• Next by Date: Re: 2.6.22-stable causes oomkiller to be invoked
• Previous by thread: Re: [PATCH] x86_64: fix problems due to use of "outb" to port 80 on some AMD64x2 laptops, etc.
• Next by thread: Re: [PATCH] x86_64: fix problems due to use of "outb" to port 80 on some AMD64x2 laptops, etc.
• Index(es):
  • Date
  • Thread

[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]