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Date: Fri, 18 Jul 1997 10:57:16 -0500 (CDT)
From: dave adkins <adkin003@gold.tc.umn.edu>
Reply-To: dave adkins <adkin003@gold.tc.umn.edu>
To: current@FreeBSD.ORG
cc: David A Adkins <adkin003@gold.tc.umn.edu>
Subject: 4M pages and XFree3.3 32 bit mode and crash
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Hi,

Since the changes in the VM subsytem to use 4M pages, X dies when loading
a background in 24 and 32 bit mode. 

Initially I thought this might just be an SMP problem, but I had the same
failure with a UP kernel. The SVGA server only supports linear address and
MMIO so I couldn't try it with those features shut off. 

It appears that when the Xserver maps a region larger than 4M,
pmap_addr_hint rounds addr to the next 4M boundary which causes the crash. 
Comment out pmap_addr_hint and the Xserver run fine in 32 bit mode. 


dave adkins
adkin003@gold.tc.umn.edu