re: port-amd64/49833: NetBSD-current (amd64/i386) reboot when start xinit on pc with HD6450

[matthew green <mrg%eterna.com.au@localhost>]

The following reply was made to PR port-amd64/49833; it has been noted by GNATS.

From: matthew green <mrg%eterna.com.au@localhost>
To: gnats-bugs%NetBSD.org@localhost
Cc: port-amd64-maintainer%netbsd.org@localhost, gnats-admin%netbsd.org@localhost,
    netbsd-bugs%netbsd.org@localhost
Subject: re: port-amd64/49833: NetBSD-current (amd64/i386) reboot when start xinit on pc with HD6450
Date: Sun, 19 Apr 2015 07:32:52 +1000

 this seems to be specific to HD6450 (at least, it doesn't happen
 on my hd5450, hd 4xxx, r300 systems.)  however, it does happen on
 the new 6450 i have.
 
 the problem seems to occur early in boot.  i patched
 radeon_bo_create() to look for the misaligned base/offset and it
 triggers before init starts:
 
 radeon0: warning: created bo 0xfffffe80bec46810 with base ffff80000573f760 offset fffffe8046364c38
 panic: kernel diagnostic assertion "(bo->tbo.mem.bus.base & (PAGE_SIZE - 1)) == 0" failed: file "/usr/src4/sys/external/bsd/drm2/dist/drm/radeon/radeon_object.c", line 205 bo bus base addr not page-aligned: ffff80000573f760
 cpu1: Begin traceback...
 vpanic() at netbsd:vpanic+0x13c
 kern_assert() at netbsd:kern_assert+0x4f
 radeon_bo_create() at netbsd:radeon_bo_create+0x23b
 radeon_ttm_init() at netbsd:radeon_ttm_init+0x171
 evergreen_init() at netbsd:evergreen_init+0xd9
 radeon_device_init() at netbsd:radeon_device_init+0x4d0
 radeon_driver_load_kms() at netbsd:radeon_driver_load_kms+0x6d
 drm_dev_register() at netbsd:drm_dev_register+0x87
 drm_pci_attach() at netbsd:drm_pci_attach+0x2d5
 radeon_attach_real() at netbsd:radeon_attach_real+0x68
 config_mountroot_thread() at netbsd:config_mountroot_thread+0x2c
 
 the "warning" is also a new message i added, so i could track
 what bo had what initial base/offset, and see where corruption
 is introduced, but i did not expect it to occur so early.
 
 
 more investigation required, but i wanted to share this info.
 
 
 .mrg.