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alloc_tag: handle incomplete bulk allocations in vm_module_tags_populate

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alloc_pages_bulk_node() may partially succeed and allocate fewer than the
requested nr_pages.  There are several conditions under which this can
occur, but we have encountered the case where CONFIG_PAGE_OWNER is enabled
causing all bulk allocations to always fallback to single page allocations
due to commit 187ad460b8 ("mm/page_alloc: avoid page allocator recursion
with pagesets.lock held").

Currently vm_module_tags_populate() immediately fails when
alloc_pages_bulk_node() returns fewer than the requested number of pages. 
When this happens memory allocation profiling gets disabled, for example

[   14.297583] [9:       modprobe:  465] Failed to allocate memory for allocation tags in the module scsc_wlan. Memory allocation profiling is disabled!
[   14.299339] [9:       modprobe:  465] modprobe: Failed to insmod '/vendor/lib/modules/scsc_wlan.ko' with args '': Out of memory

This patch causes vm_module_tags_populate() to retry bulk allocations for
the remaining memory instead of failing immediately which will avoid the
disablement of memory allocation profiling.

Link: https://lkml.kernel.org/r/20250409225111.3770347-1-tjmercier@google.com
Fixes: 0f9b685626 ("alloc_tag: populate memory for module tags as needed")
Signed-off-by: T.J. Mercier <tjmercier@google.com>
Reported-by: Janghyuck Kim <janghyuck.kim@samsung.com>
Acked-by: Suren Baghdasaryan <surenb@google.com>
Cc: Kent Overstreet <kent.overstreet@linux.dev>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
This commit is contained in:
T.J. Mercier 2025-04-09 22:51:11 +00:00 • committed by Andrew Morton
parent 0aa8dbe5a8
commit e6e07b696d
1 changed files with 12 additions and 3 deletions
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15
lib/alloc_tag.c
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@ -422,11 +422,20 @@ static int vm_module_tags_populate(void)
unsigned long old_shadow_end = ALIGN(phys_end, MODULE_ALIGN);
unsigned long new_shadow_end = ALIGN(new_end, MODULE_ALIGN);
unsigned long more_pages;
unsigned long nr;
unsigned long nr = 0;
more_pages = ALIGN(new_end - phys_end, PAGE_SIZE) >> PAGE_SHIFT;
nr = alloc_pages_bulk_node(GFP_KERNEL | __GFP_NOWARN,
NUMA_NO_NODE, more_pages, next_page);
while (nr < more_pages) {
unsigned long allocated;
allocated = alloc_pages_bulk_node(GFP_KERNEL | __GFP_NOWARN,
NUMA_NO_NODE, more_pages - nr, next_page + nr);
if (!allocated)
break;
nr += allocated;
}
if (nr < more_pages ||
vmap_pages_range(phys_end, phys_end + (nr << PAGE_SHIFT), PAGE_KERNEL,
next_page, PAGE_SHIFT) < 0) {