From: Hirokazu Takahashi Hi Dave, I found a bug. Would you apply the following patch, please. The patch is against 2.6.11-rc1-mm1-mhp1 and should be applied right after AA-PM-10.3-rename_rewind_page_to_unwind_page.patch . > Well, here it is, the grand new nonlinear implementation. The fun part > is, it's only half of nonlinear for now. What Andy Whitcroft did was > split nonlinear up into two pieces: > > http://sr71.net/patches/2.6.11/2.6.11-rc1-mm1-mhp1/ > http://sr71.net/patches/2.6.11/2.6.11-rc1-mm1-mhp1/patch-2.6.11-rc1-mm1-mhp1.gz > > the one config that I know compiles: > http://sr71.net/patches/2.6.11/2.6.11-rc1-mm1-mhp1/configs/config-i386-sparse-hotplug unwind() may cause Oops if the inode which the target page belongs is just removing and the page is under writeback, as end_page_writeback() tries to refer the inode via newpage->mapping which may not exit anymore. newpage->mapping should be set NULL before calling end_page_writeback(). Signed-off-by: Dave Hansen --- memhotplug-dave/mm/mmigrate.c | 2 +- 1 files changed, 1 insertion(+), 1 deletion(-) diff -puN mm/mmigrate.c~AA-PM-32-unwind_may_cause_Oops_against_removing_pages mm/mmigrate.c --- memhotplug/mm/mmigrate.c~AA-PM-32-unwind_may_cause_Oops_against_removing_pages 2005-03-28 16:38:17.000000000 -0800 +++ memhotplug-dave/mm/mmigrate.c 2005-03-28 16:38:17.000000000 -0800 @@ -195,9 +195,9 @@ unwind_page(struct page *page, struct pa /* no page_cache_get(page); needed */ read_unlock_irq(&mapping->tree_lock); out: + newpage->mapping = NULL; if (PageWriteback(newpage)) end_page_writeback(newpage); /* XXX */ - newpage->mapping = NULL; newpage->private = 0; ClearPageSwapCache(newpage); /* XXX unmap needed? No, it shouldn't. Handled by fault handlers. */ _