The patch titled mm: print vmalloc() state after allocation failures has been added to the -mm tree. Its filename is mm-print-vmalloc-state-after-allocation-failures.patch Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/SubmitChecklist when testing your code *** See http://userweb.kernel.org/~akpm/stuff/added-to-mm.txt to find out what to do about this The current -mm tree may be found at http://userweb.kernel.org/~akpm/mmotm/ ------------------------------------------------------ Subject: mm: print vmalloc() state after allocation failures From: Dave Hansen <dave@xxxxxxxxxxxxxxxxxx> I was tracking down a page allocation failure that ended up in vmalloc(). Since vmalloc() uses 0-order pages, if somebody asks for an insane amount of memory, we'll still get a warning with "order:0" in it. That's not very useful. During recovery, vmalloc() also nicely frees all of the memory that it got up to the point of the failure. That is wonderful, but it also quickly hides any issues. We have a much different sitation if vmalloc() repeatedly fails 10GB in to: vmalloc(100 * 1<<30); versus repeatedly failing 4096 bytes in to a: vmalloc(8192); This patch will print out messages that look like this: [ 68.123503] vmalloc: allocation failure, allocated 6680576 of 13426688 bytes [ 68.124218] bash: page allocation failure: order:0, mode:0xd2 [ 68.124811] Pid: 3770, comm: bash Not tainted 2.6.39-rc3-00082-g85f2e68-dirty #333 [ 68.125579] Call Trace: [ 68.125853] [<ffffffff810f6da6>] warn_alloc_failed+0x146/0x170 [ 68.126464] [<ffffffff8107e05c>] ? printk+0x6c/0x70 [ 68.126791] [<ffffffff8112b5d4>] ? alloc_pages_current+0x94/0xe0 [ 68.127661] [<ffffffff8111ed37>] __vmalloc_node_range+0x237/0x290 ... The 'order' variable is added for clarity when calling warn_alloc_failed() to avoid having an unexplained '0' as an argument. The 'tmp_mask' is because adding an open-coded '| __GFP_NOWARN' would take us over 80 columns for the alloc_pages_node() call. If we are going to add a line, it might as well be one that makes the sucker easier to read. As a side issue, I also noticed that ctl_ioctl() does vmalloc() based solely on an unverified value passed in from userspace. Granted, it's under CAP_SYS_ADMIN, but it still frightens me a bit. Signed-off-by: Dave Hansen <dave@xxxxxxxxxxxxxxxxxx> Cc: Johannes Weiner <hannes@xxxxxxxxxxx> Cc: David Rientjes <rientjes@xxxxxxxxxx> Cc: Michal Nazarewicz <mina86@xxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- mm/vmalloc.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) diff -puN mm/vmalloc.c~mm-print-vmalloc-state-after-allocation-failures mm/vmalloc.c --- a/mm/vmalloc.c~mm-print-vmalloc-state-after-allocation-failures +++ a/mm/vmalloc.c @@ -1534,6 +1534,7 @@ static void *__vmalloc_node(unsigned lon static void *__vmalloc_area_node(struct vm_struct *area, gfp_t gfp_mask, pgprot_t prot, int node, void *caller) { + const int order = 0; struct page **pages; unsigned int nr_pages, array_size, i; gfp_t nested_gfp = (gfp_mask & GFP_RECLAIM_MASK) | __GFP_ZERO; @@ -1560,11 +1561,12 @@ static void *__vmalloc_area_node(struct for (i = 0; i < area->nr_pages; i++) { struct page *page; + gfp_t tmp_mask = gfp_mask | __GFP_NOWARN; if (node < 0) - page = alloc_page(gfp_mask); + page = alloc_page(tmp_mask); else - page = alloc_pages_node(node, gfp_mask, 0); + page = alloc_pages_node(node, tmp_mask, order); if (unlikely(!page)) { /* Successfully allocated i pages, free them in __vunmap() */ @@ -1579,6 +1581,9 @@ static void *__vmalloc_area_node(struct return area->addr; fail: + warn_alloc_failed(gfp_mask, order, "vmalloc: allocation failure, " + "allocated %ld of %ld bytes\n", + (area->nr_pages*PAGE_SIZE), area->size); vfree(area->addr); return NULL; } _ Patches currently in -mm which might be from dave@xxxxxxxxxxxxxxxxxx are mm-increase-reclaim_distance-to-30.patch mm-convert-vma-vm_flags-to-64-bit.patch mm-add-__nocast-attribute-to-vm_flags.patch fremap-convert-vm_flags-to-unsigned-long-long.patch procfs-convert-vm_flags-to-unsigned-long-long.patch include-linux-gfph-work-around-apparent-sparse-confusion.patch include-linux-gfph-convert-bug_on-into-vm_bug_on.patch mm-rename-alloc_pages_exact.patch mm-make-new-alloc_pages_exact.patch mm-reuse-__free_pages_exact-in-__alloc_pages_exact.patch mm-break-out-page-allocation-warning-code.patch mm-print-vmalloc-state-after-allocation-failures.patch sparse-define-dummy-build_bug_on-definition-for-sparse.patch sparse-define-__must_be_array-for-__checker__.patch sparse-undef-__compiletime_warningerror-if-__checker__-is-defined.patch -- To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html