Hi David, Yes, there are a lot of differences.
Did you try other protections flags like VM_IO (I think this is selected automatically in mem.c) and VM_RESERVED? Fred -----Original Message----- From: David Ashley To: linuxppc-embedded at lists.linuxppc.org Sent: 2/14/02 6:06 PM Subject: RE: Linux 2.4.17 bug, mmap of /dev/mem Hmmm. Too many differences, the biggest being 2.4.17 vs 2.4.2. I forgot to mention to the mailing list that the order of reads/writes to a page matters. In every mmap'd page, if the access order is: reads only = no problem writes only = no problem write, read, then anything = no problem read, write = trouble Each page is a separate entity. Meaning if I mmap 2 pages of /dev/mem, then write to page 0, I'll not have any trouble from page 0 from then on. But if I read from page 1, then write to page 1, there is a chance of corrupting linux. -Dave >Hi David, > >I tested your application on my board (Embedded Planet CLLF (mpc860), Linux >2.4.2) and made a script that executes it as fast as possible. >I let it run for 10 minutes on several telnet sessions simultaneously but I >do not see anything strange... The memory I write to is NVRAM. > >Frederic ** Sent via the linuxppc-embedded mail list. See http://lists.linuxppc.org/
