Reposting from this kernel bug: https://bugzilla.kernel.org/show_bug.cgi?id=50241
I've tested the patch and it solves a highly repeatable OOPS with the CedarView driver that I'm porting.
From 3552913d3a1c2d3c4ce158e91dc18cd12b522cb2 Mon Sep 17 00:00:00 2001 From: Yakui Zhao yakui.zhao@intel.com Date: Tue, 7 Feb 2012 15:33:13 -0500 Subject: [PATCH] Clear the ttm page allocated from high memory zone correctly
The TTM page can be allocated from high memory. In such case it is wrong to use the page_address(page) as the virtual address for the high memory page.
Signed-off-by: Zhao Yakui yakui.zhao@intel.com --- drivers/gpu/drm/ttm/ttm_page_alloc.c | 5 ++++- 1 files changed, 4 insertions(+), 1 deletions(-)
diff --git a/drivers/gpu/drm/ttm/ttm_page_alloc.c b/drivers/gpu/drm/ttm/ttm_page_alloc.c index d948575..df976d9 100644 --- a/drivers/gpu/drm/ttm/ttm_page_alloc.c +++ b/drivers/gpu/drm/ttm/ttm_page_alloc.c @@ -708,7 +708,10 @@ int ttm_get_pages(struct list_head *pages, int flags, /* clear the pages coming from the pool if requested */ if (flags & TTM_PAGE_FLAG_ZERO_ALLOC) { list_for_each_entry(p, pages, lru) { - clear_page(page_address(p)); + if (PageHighMem(p)) + clear_highpage(p); + else + clear_page(page_address(p)); } }
On 11/13/2012 07:31 PM, Jonathan Morton wrote:
Reposting from this kernel bug: https://bugzilla.kernel.org/show_bug.cgi?id=50241
I've tested the patch and it solves a highly repeatable OOPS with the CedarView driver that I'm porting.
From 3552913d3a1c2d3c4ce158e91dc18cd12b522cb2 Mon Sep 17 00:00:00 2001
From: Yakui Zhao yakui.zhao@intel.com Date: Tue, 7 Feb 2012 15:33:13 -0500 Subject: [PATCH] Clear the ttm page allocated from high memory zone correctly
The TTM page can be allocated from high memory. In such case it is wrong to use the page_address(page) as the virtual address for the high memory page.
Signed-off-by: Zhao Yakui yakui.zhao@intel.com
drivers/gpu/drm/ttm/ttm_page_alloc.c | 5 ++++- 1 files changed, 4 insertions(+), 1 deletions(-)
diff --git a/drivers/gpu/drm/ttm/ttm_page_alloc.c b/drivers/gpu/drm/ttm/ttm_page_alloc.c index d948575..df976d9 100644 --- a/drivers/gpu/drm/ttm/ttm_page_alloc.c +++ b/drivers/gpu/drm/ttm/ttm_page_alloc.c @@ -708,7 +708,10 @@ int ttm_get_pages(struct list_head *pages, int flags, /* clear the pages coming from the pool if requested */ if (flags & TTM_PAGE_FLAG_ZERO_ALLOC) { list_for_each_entry(p, pages, lru) {
clear_page(page_address(p));
if (PageHighMem(p))clear_highpage(p);elseclear_page(page_address(p));
This is a pretty bad bug. I think the only reason it hasn't been hit more often is that TTM_PAGE_FLAG_ZERO_ALLOC may not be used that often. Please resend this patch with
Cc: stable@vger.kernel.org Reviewed-by: Thomas Hellstrom thellstrom@vmware.com
Thanks, Thomas
dri-devel@lists.freedesktop.org
-
Jonathan Morton -
Thomas Hellstrom