Mike Kravetz 6d86b4ceb0 mm: hugetlb: proc: check for hugetlb shared PMD in /proc/PID/smaps ... commit 3489dbb696 upstream. Patch series "Fixes for hugetlb mapcount at most 1 for shared PMDs". This issue of mapcount in hugetlb pages referenced by shared PMDs was discussed in [1]. The following two patches address user visible behavior caused by this issue. [1] https://lore.kernel.org/linux-mm/Y9BF+OCdWnCSilEu@monkey/ This patch (of 2): A hugetlb page will have a mapcount of 1 if mapped by multiple processes via a shared PMD. This is because only the first process increases the map count, and subsequent processes just add the shared PMD page to their page table. page_mapcount is being used to decide if a hugetlb page is shared or private in /proc/PID/smaps. Pages referenced via a shared PMD were incorrectly being counted as private. To fix, check for a shared PMD if mapcount is 1. If a shared PMD is found count the hugetlb page as shared. A new helper to check for a shared PMD is added. [akpm@linux-foundation.org: simplification, per David] [akpm@linux-foundation.org: hugetlb.h: include page_ref.h for page_count()] Link: https://lkml.kernel.org/r/20230126222721.222195-2-mike.kravetz@oracle.com Fixes: 25ee01a2fc ("mm: hugetlb: proc: add hugetlb-related fields to /proc/PID/smaps") Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com> Acked-by: Peter Xu <peterx@redhat.com> Cc: David Hildenbrand <david@redhat.com> Cc: James Houghton <jthoughton@google.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Muchun Song <songmuchun@bytedance.com> Cc: Naoya Horiguchi <naoya.horiguchi@linux.dev> Cc: Vishal Moola (Oracle) <vishal.moola@gmail.com> Cc: Yang Shi <shy828301@gmail.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>		2023-02-22 12:50:28 +01:00
..
acpi	ACPI: CPPC: Do not prevent CPPC from working in the future	2022-08-25 11:18:15 +02:00
asm-generic	mm/khugepaged: fix GUP-fast interaction by sending IPI	2022-12-14 11:30:42 +01:00
clocksource
crypto	crypto: drbg - make reseeding from get_random_bytes() synchronous	2022-06-22 14:11:18 +02:00
drm	drm: fix EDID struct for old ARM OABI format	2022-06-14 18:11:31 +02:00
dt-bindings
keys
kvm
linux	mm: hugetlb: proc: check for hugetlb shared PMD in /proc/PID/smaps	2023-02-22 12:50:28 +01:00
math-emu
media	media: dvbdev: fix build warning due to comments	2023-01-18 11:41:42 +01:00
misc
net	l2tp: Serialize access to sk_user_data with sk_callback_lock	2023-02-06 07:52:37 +01:00
pcmcia
ras
rdma	RDMA/netlink: Add __maybe_unused to static inline in C file	2021-11-26 10:47:18 +01:00
scsi	scsi: stex: Properly zero out the passthrough command structure	2022-10-15 07:54:39 +02:00
soc
sound	ALSA: hda: add snd_hdac_stop_streams() helper	2023-01-18 11:41:39 +01:00
target	scsi: target: Fix ordered tag handling	2021-11-26 10:47:16 +01:00
trace	jbd2: use the correct print format	2023-01-18 11:42:02 +01:00
uapi	netfilter: conntrack: unify established states for SCTP paths	2023-02-06 07:52:47 +01:00
vdso
video	video: of_display_timing.h: include errno.h	2022-07-12 16:30:47 +02:00
xen	xen/gnttab: fix gnttab_end_foreign_access() without page specified	2022-03-11 11:22:39 +01:00