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authorJakub Kicinski <kuba@kernel.org>2023-06-08 11:34:28 -0700
committerJakub Kicinski <kuba@kernel.org>2023-06-08 11:35:14 -0700
commit449f6bc17a51e68b06cfd742898e5ff3fe6e04d7 (patch)
treeed59929e7d1fa057ac6998075986a4cdfb85eb5a /include/linux/page-flags.h
parentbfd019d10fdabf70f9b01264aea6d6c7595f9226 (diff)
parent25041a4c02c7cf774d8b6ed60586fd64f1cdaa81 (diff)
Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Cross-merge networking fixes after downstream PR. Conflicts: net/sched/sch_taprio.c d636fc5dd692 ("net: sched: add rcu annotations around qdisc->qdisc_sleeping") dced11ef84fb ("net/sched: taprio: don't overwrite "sch" variable in taprio_dump_class_stats()") net/ipv4/sysctl_net_ipv4.c e209fee4118f ("net/ipv4: ping_group_range: allow GID from 2147483648 to 4294967294") ccce324dabfe ("tcp: make the first N SYN RTO backoffs linear") https://lore.kernel.org/all/20230605100816.08d41a7b@canb.auug.org.au/ No adjacent changes. Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Diffstat (limited to 'include/linux/page-flags.h')
-rw-r--r--include/linux/page-flags.h6
1 files changed, 6 insertions, 0 deletions
diff --git a/include/linux/page-flags.h b/include/linux/page-flags.h
index 1c68d67b832f..92a2063a0a23 100644
--- a/include/linux/page-flags.h
+++ b/include/linux/page-flags.h
@@ -617,6 +617,12 @@ PAGEFLAG_FALSE(VmemmapSelfHosted, vmemmap_self_hosted)
* Please note that, confusingly, "page_mapping" refers to the inode
* address_space which maps the page from disk; whereas "page_mapped"
* refers to user virtual address space into which the page is mapped.
+ *
+ * For slab pages, since slab reuses the bits in struct page to store its
+ * internal states, the page->mapping does not exist as such, nor do these
+ * flags below. So in order to avoid testing non-existent bits, please
+ * make sure that PageSlab(page) actually evaluates to false before calling
+ * the following functions (e.g., PageAnon). See mm/slab.h.
*/
#define PAGE_MAPPING_ANON 0x1
#define PAGE_MAPPING_MOVABLE 0x2