Re: [patch -mm series] ia64 specific /dev/mem handlers

Andrew Morton
2005-03-03T11:37:04Z

jes@trained-monkey.org (Jes Sorensen) wrote:
>
> This patch introduces ia64 specific read/write handlers for /dev/mem
> access which is needed to avoid uncached pages to be accessed through
> the cached kernel window which can lead to random corruption.

This patch causes hiccups on my ia32e box.

linux:/home/akpm# /usr/sbin/hwscan --isapnp
zsh: 7528 segmentation fault /usr/sbin/hwscan --isapnp
linux:/home/akpm# /usr/sbin/hwscan --pci
zsh: 7529 segmentation fault /usr/sbin/hwscan --pci
linux:/home/akpm# /usr/sbin/hwscan --block
zsh: 7530 segmentation fault /usr/sbin/hwscan --block
linux:/home/akpm# /usr/sbin/hwscan --floppy
zsh: 7533 segmentation fault /usr/sbin/hwscan --floppy

strace ends with:

open("/proc/apm", O_RDONLY) = -1 ENOENT (No such file or directory)
open("/dev/mem", O_RDONLY) = 3
lseek(3, 1024, SEEK_SET) = 1024
read(3, 0x50a080, 256) = -1 EFAULT (Bad address)
close(3) = 0
--- SIGSEGV (Segmentation fault) @ 0 (0) ---
+++ killed by SIGSEGV +++