Mike Kravetz fdf40e5824 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>		2023-02-09 11:26:44 +01:00
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Kconfig	…
Makefile	…
array.c	proc: stop using seq_get_buf in proc_task_name	2021-09-08 11:50:25 -07:00
base.c	proc: fix a dentry lock race between release_task and lookup	2022-08-17 14:24:08 +02:00
bootconfig.c	proc: bootconfig: Add null pointer check	2022-04-08 14:24:12 +02:00
cmdline.c	…
consoles.c	…
cpuinfo.c	…
devices.c	…
fd.c	procfs: prevent unprivileged processes accessing fdinfo dir	2022-05-18 10:26:50 +02:00
fd.h	…
generic.c	proc: fix dentry/inode overinstantiating under /proc/${pid}/net	2022-06-09 10:23:10 +02:00
inode.c	proc: delete redundant subset=pid check	2021-05-06 19:24:11 -07:00
internal.h	…
interrupts.c	…
kcore.c	fs/proc/kcore: use page_offline_(freeze|thaw)	2021-06-30 20:47:28 -07:00
kmsg.c	…
loadavg.c	sched: Make nr_running() return 32-bit value	2021-05-12 21:34:14 +02:00
meminfo.c	mm: memcontrol: convert NR_FILE_PMDMAPPED account to pages	2021-02-24 13:38:29 -08:00
namespaces.c	…
nommu.c	…
page.c	…
proc_net.c	proc: fix dentry/inode overinstantiating under /proc/${pid}/net	2022-06-09 10:23:10 +02:00
proc_sysctl.c	sysctl: add a new register_sysctl_init() interface	2023-02-01 08:27:19 +01:00
proc_tty.c	…
root.c	…
self.c	…
softirqs.c	…
stat.c	fs/proc/uptime.c: Fix idle time reporting in /proc/uptime	2021-11-18 19:16:13 +01:00
task_mmu.c	mm: hugetlb: proc: check for hugetlb shared PMD in /proc/PID/smaps	2023-02-09 11:26:44 +01:00
task_nommu.c	…
thread_self.c	…
uptime.c	fs/proc/uptime.c: Fix idle time reporting in /proc/uptime	2021-11-18 19:16:13 +01:00
util.c	…
version.c	…
vmcore.c	proc/vmcore: fix clearing user buffer by properly using clear_user()	2021-12-01 09:04:44 +01:00