[PATCH] unpaged: sound nopage get_page
authorHugh Dickins <hugh@veritas.com>
Tue, 22 Nov 2005 05:32:13 +0000 (21:32 -0800)
committerLinus Torvalds <torvalds@g5.osdl.org>
Tue, 22 Nov 2005 17:13:42 +0000 (09:13 -0800)
commit1cdca61bf8537043edde8ef784ce1a1351361dac
treedb9d45f8616240758cea40f5f657879f47f058fe
parent83e9b7e929d1323b9a155d186f77aa8c06155cc3
[PATCH] unpaged: sound nopage get_page

Something noticed when studying use of VM_RESERVED in different drivers:
snd_usX2Y_hwdep_pcm_vm_nopage omitted to get_page: fixed.

And how did this work before?  Aargh!  That nopage is returning a page from
within a buffer allocated by snd_malloc_pages, which allocates a high-order
page, then does SetPageReserved on each 0-order page within.

That would have worked in 2.6.14, because when the area was unmapped,
PageReserved inhibited put_page.  2.6.15-rc1 removed that inhibition (while
leaving ineffective PageReserveds around for now), but it hasn't caused
trouble because..  we've not been freeing from VM_RESERVED at all.

Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
sound/usb/usx2y/usx2yhwdeppcm.c