Subject: Re: CVS commit: src
To: None <firstname.lastname@example.org>
From: Jason Thorpe <email@example.com>
Date: 12/05/1998 14:34:40
On Sat, 5 Dec 1998 01:13:11 -0800 (PST)
Jonathan Stone <firstname.lastname@example.org> wrote:
> Module Name: src
> Committed By: jonathan
> Date: Sat Dec 5 09:13:10 UTC 1998
> Modified Files:
> src/sys/arch/mips/mips: pmap.c
> Log Message:
> Track PV_REFERENCED bit as for PV_MODIFIED, to make mdsetimage work correctly.
> Compatiblity with Mach VM: clear pmap-private bits in pmap_remove() if !UVM.
That latter bit is WRONG. For example, the hp300 pmap SPECIFICALLY remembers
the ref/mod bits from the PTE in the pmap_attributes entry for that page
when a mapping is removed.
"referenced" and "modifed" are attributes of the hardware page, not the
mapping of it. Consider if a page is double-mapped. With your change,
you have now broken mod/ref tracking for double-mapped pages when one
of the mappings is removed.
Jason R. Thorpe email@example.com
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