CVS commit: src/sys/uvm

["Rin Okuyama" <rin%netbsd.org@localhost>]

Module Name:    src
Committed By:   rin
Date:           Thu Jul  9 09:24:33 UTC 2020

Modified Files:
        src/sys/uvm: uvm_bio.c

Log Message:
PR kern/55467
tmpfs calls pmap_kenter_pa(9) with virtual address with page offset

Bisectioning revealed that the failure starts with this commit:

sys/fs/tmpfs/tmpfs_vnops.c rev 1.142:
http://cvsweb.netbsd.org/bsdweb.cgi/src/sys/fs/tmpfs/tmpfs_vnops.c#rev1.142

by which tmpfs became to use UBC_FAULTBUSY flag for ubc_uiomove(9).
If this flag is specified, pmap_kenter_pa(9) is called with virtual
address with page offset via ubc_alloc(9):

https://nxr.netbsd.org/xref/src/sys/uvm/uvm_bio.c#616

Most ports seem to neglect silently page offset of va argument for
pmap_kenter_pa(9). However, it causes KASSERT failure correctly for
powerpc/booke. So, truncate page offset there.

Now, tmpfs works just fine on evbppc-booke, and I've confirmed that
no new failures are detected by ATF.

Discussed with chs@. Thanks!


To generate a diff of this commit:
cvs rdiff -u -r1.120 -r1.121 src/sys/uvm/uvm_bio.c

Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.