diff options
| author | Jan Beulich <jbeulich@novell.com> | 2008-06-18 09:28:00 +0100 |
|---|---|---|
| committer | Dave Airlie <airlied@redhat.com> | 2008-06-19 09:56:16 +1000 |
| commit | da503fa60b84d5945deb3ab74efdd0bec61df4a1 (patch) | |
| tree | 9883d28cabdab419567a2c0689d06c938460eaa1 /drivers/char/agp/generic.c | |
| parent | dcd981a77b2b35d169656d4b9cee208096ed7ccf (diff) | |
| download | linux-3.10-da503fa60b84d5945deb3ab74efdd0bec61df4a1.tar.gz linux-3.10-da503fa60b84d5945deb3ab74efdd0bec61df4a1.tar.bz2 linux-3.10-da503fa60b84d5945deb3ab74efdd0bec61df4a1.zip | |
agp: two-stage page destruction issue
besides it apparently being useful only in 2.6.24 (the changes in 2.6.25
really mean that it could be converted back to a single-stage mechanism),
I'm seeing an issue in Xen Dom0 kernels, which is caused by the calling
of gart_to_virt() in the second stage invocations of the destroy function.
I think that besides this being a real issue with Xen (where
unmap_page_from_agp() is not just a page table attribute change), this
also is invalid from a theoretical perspective: One should not assume that
gart_to_virt() is still valid after unmapping a page. So minimally (keeping
the 2-stage mechanism) a patch like the one below would be needed.
Jan
Signed-off-by: Dave Airlie <airlied@redhat.com>
Diffstat (limited to 'drivers/char/agp/generic.c')
| -rw-r--r-- | drivers/char/agp/generic.c | 7 |
1 files changed, 5 insertions, 2 deletions
diff --git a/drivers/char/agp/generic.c b/drivers/char/agp/generic.c index 7fc0c99a3a5..b6650a63197 100644 --- a/drivers/char/agp/generic.c +++ b/drivers/char/agp/generic.c @@ -202,10 +202,13 @@ void agp_free_memory(struct agp_memory *curr) } if (curr->page_count != 0) { for (i = 0; i < curr->page_count; i++) { - curr->bridge->driver->agp_destroy_page(gart_to_virt(curr->memory[i]), AGP_PAGE_DESTROY_UNMAP); + curr->memory[i] = (unsigned long)gart_to_virt(curr->memory[i]); + curr->bridge->driver->agp_destroy_page((void *)curr->memory[i], + AGP_PAGE_DESTROY_UNMAP); } for (i = 0; i < curr->page_count; i++) { - curr->bridge->driver->agp_destroy_page(gart_to_virt(curr->memory[i]), AGP_PAGE_DESTROY_FREE); + curr->bridge->driver->agp_destroy_page((void *)curr->memory[i], + AGP_PAGE_DESTROY_FREE); } } agp_free_key(curr->key); |