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Author SHA1 Message Date
David Hildenbrand
4ca9b3859d mm/madvise: introduce MADV_POPULATE_(READ|WRITE) to prefault page tables
I. Background: Sparse Memory Mappings

When we manage sparse memory mappings dynamically in user space - also
sometimes involving MAP_NORESERVE - we want to dynamically populate/
discard memory inside such a sparse memory region.  Example users are
hypervisors (especially implementing memory ballooning or similar
technologies like virtio-mem) and memory allocators.  In addition, we want
to fail in a nice way (instead of generating SIGBUS) if populating does
not succeed because we are out of backend memory (which can happen easily
with file-based mappings, especially tmpfs and hugetlbfs).

While MADV_DONTNEED, MADV_REMOVE and FALLOC_FL_PUNCH_HOLE allow for
reliably discarding memory for most mapping types, there is no generic
approach to populate page tables and preallocate memory.

Although mmap() supports MAP_POPULATE, it is not applicable to the concept
of sparse memory mappings, where we want to populate/discard dynamically
and avoid expensive/problematic remappings.  In addition, we never
actually report errors during the final populate phase - it is best-effort
only.

fallocate() can be used to preallocate file-based memory and fail in a
safe way.  However, it cannot really be used for any private mappings on
anonymous files via memfd due to COW semantics.  In addition, fallocate()
does not actually populate page tables, so we still always get pagefaults
on first access - which is sometimes undesired (i.e., real-time workloads)
and requires real prefaulting of page tables, not just a preallocation of
backend storage.  There might be interesting use cases for sparse memory
regions along with mlockall(MCL_ONFAULT) which fallocate() cannot satisfy
as it does not prefault page tables.

II. On preallcoation/prefaulting from user space

Because we don't have a proper interface, what applications (like QEMU and
databases) end up doing is touching (i.e., reading+writing one byte to not
overwrite existing data) all individual pages.

However, that approach
1) Can result in wear on storage backing, because we end up reading/writing
   each page; this is especially a problem for dax/pmem.
2) Can result in mmap_sem contention when prefaulting via multiple
   threads.
3) Requires expensive signal handling, especially to catch SIGBUS in case
   of hugetlbfs/shmem/file-backed memory. For example, this is
   problematic in hypervisors like QEMU where SIGBUS handlers might already
   be used by other subsystems concurrently to e.g, handle hardware errors.
   "Simply" doing preallocation concurrently from other thread is not that
   easy.

III. On MADV_WILLNEED

Extending MADV_WILLNEED is not an option because
1. It would change the semantics: "Expect access in the near future." and
   "might be a good idea to read some pages" vs. "Definitely populate/
   preallocate all memory and definitely fail on errors.".
2. Existing users (like virtio-balloon in QEMU when deflating the balloon)
   don't want populate/prealloc semantics. They treat this rather as a hint
   to give a little performance boost without too much overhead - and don't
   expect that a lot of memory might get consumed or a lot of time
   might be spent.

IV. MADV_POPULATE_READ and MADV_POPULATE_WRITE

Let's introduce MADV_POPULATE_READ and MADV_POPULATE_WRITE, inspired by
MAP_POPULATE, with the following semantics:
1. MADV_POPULATE_READ can be used to prefault page tables just like
   manually reading each individual page. This will not break any COW
   mappings. The shared zero page might get mapped and no backend storage
   might get preallocated -- allocation might be deferred to
   write-fault time. Especially shared file mappings require an explicit
   fallocate() upfront to actually preallocate backend memory (blocks in
   the file system) in case the file might have holes.
2. If MADV_POPULATE_READ succeeds, all page tables have been populated
   (prefaulted) readable once.
3. MADV_POPULATE_WRITE can be used to preallocate backend memory and
   prefault page tables just like manually writing (or
   reading+writing) each individual page. This will break any COW
   mappings -- e.g., the shared zeropage is never populated.
4. If MADV_POPULATE_WRITE succeeds, all page tables have been populated
   (prefaulted) writable once.
5. MADV_POPULATE_READ and MADV_POPULATE_WRITE cannot be applied to special
   mappings marked with VM_PFNMAP and VM_IO. Also, proper access
   permissions (e.g., PROT_READ, PROT_WRITE) are required. If any such
   mapping is encountered, madvise() fails with -EINVAL.
6. If MADV_POPULATE_READ or MADV_POPULATE_WRITE fails, some page tables
   might have been populated.
7. MADV_POPULATE_READ and MADV_POPULATE_WRITE will return -EHWPOISON
   when encountering a HW poisoned page in the range.
8. Similar to MAP_POPULATE, MADV_POPULATE_READ and MADV_POPULATE_WRITE
   cannot protect from the OOM (Out Of Memory) handler killing the
   process.

While the use case for MADV_POPULATE_WRITE is fairly obvious (i.e.,
preallocate memory and prefault page tables for VMs), one issue is that
whenever we prefault pages writable, the pages have to be marked dirty,
because the CPU could dirty them any time.  while not a real problem for
hugetlbfs or dax/pmem, it can be a problem for shared file mappings: each
page will be marked dirty and has to be written back later when evicting.

MADV_POPULATE_READ allows for optimizing this scenario: Pre-read a whole
mapping from backend storage without marking it dirty, such that eviction
won't have to write it back.  As discussed above, shared file mappings
might require an explciit fallocate() upfront to achieve
preallcoation+prepopulation.

Although sparse memory mappings are the primary use case, this will also
be useful for other preallocate/prefault use cases where MAP_POPULATE is
not desired or the semantics of MAP_POPULATE are not sufficient: as one
example, QEMU users can trigger preallocation/prefaulting of guest RAM
after the mapping was created -- and don't want errors to be silently
suppressed.

Looking at the history, MADV_POPULATE was already proposed in 2013 [1],
however, the main motivation back than was performance improvements --
which should also still be the case.

V. Single-threaded performance comparison

I did a short experiment, prefaulting page tables on completely *empty
mappings/files* and repeated the experiment 10 times.  The results
correspond to the shortest execution time.  In general, the performance
benefit for huge pages is negligible with small mappings.

V.1: Private mappings

POPULATE_READ and POPULATE_WRITE is fastest.  Note that
Reading/POPULATE_READ will populate the shared zeropage where applicable
-- which result in short population times.

The fastest way to allocate backend storage (here: swap or huge pages) and
prefault page tables is POPULATE_WRITE.

V.2: Shared mappings

fallocate() is fastest, however, doesn't prefault page tables.
POPULATE_WRITE is faster than simple writes and read/writes.
POPULATE_READ is faster than simple reads.

Without a fd, the fastest way to allocate backend storage and prefault
page tables is POPULATE_WRITE.  With an fd, the fastest way is usually
FALLOCATE+POPULATE_READ or FALLOCATE+POPULATE_WRITE respectively; one
exception are actual files: FALLOCATE+Read is slightly faster than
FALLOCATE+POPULATE_READ.

The fastest way to allocate backend storage prefault page tables is
FALLOCATE+POPULATE_WRITE -- except when dealing with actual files; then,
FALLOCATE+POPULATE_READ is fastest and won't directly mark all pages as
dirty.

v.3: Detailed results

==================================================
2 MiB MAP_PRIVATE:
**************************************************
Anon 4 KiB     : Read                     :     0.119 ms
Anon 4 KiB     : Write                    :     0.222 ms
Anon 4 KiB     : Read/Write               :     0.380 ms
Anon 4 KiB     : POPULATE_READ            :     0.060 ms
Anon 4 KiB     : POPULATE_WRITE           :     0.158 ms
Memfd 4 KiB    : Read                     :     0.034 ms
Memfd 4 KiB    : Write                    :     0.310 ms
Memfd 4 KiB    : Read/Write               :     0.362 ms
Memfd 4 KiB    : POPULATE_READ            :     0.039 ms
Memfd 4 KiB    : POPULATE_WRITE           :     0.229 ms
Memfd 2 MiB    : Read                     :     0.030 ms
Memfd 2 MiB    : Write                    :     0.030 ms
Memfd 2 MiB    : Read/Write               :     0.030 ms
Memfd 2 MiB    : POPULATE_READ            :     0.030 ms
Memfd 2 MiB    : POPULATE_WRITE           :     0.030 ms
tmpfs          : Read                     :     0.033 ms
tmpfs          : Write                    :     0.313 ms
tmpfs          : Read/Write               :     0.406 ms
tmpfs          : POPULATE_READ            :     0.039 ms
tmpfs          : POPULATE_WRITE           :     0.285 ms
file           : Read                     :     0.033 ms
file           : Write                    :     0.351 ms
file           : Read/Write               :     0.408 ms
file           : POPULATE_READ            :     0.039 ms
file           : POPULATE_WRITE           :     0.290 ms
hugetlbfs      : Read                     :     0.030 ms
hugetlbfs      : Write                    :     0.030 ms
hugetlbfs      : Read/Write               :     0.030 ms
hugetlbfs      : POPULATE_READ            :     0.030 ms
hugetlbfs      : POPULATE_WRITE           :     0.030 ms
**************************************************
4096 MiB MAP_PRIVATE:
**************************************************
Anon 4 KiB     : Read                     :   237.940 ms
Anon 4 KiB     : Write                    :   708.409 ms
Anon 4 KiB     : Read/Write               :  1054.041 ms
Anon 4 KiB     : POPULATE_READ            :   124.310 ms
Anon 4 KiB     : POPULATE_WRITE           :   572.582 ms
Memfd 4 KiB    : Read                     :   136.928 ms
Memfd 4 KiB    : Write                    :   963.898 ms
Memfd 4 KiB    : Read/Write               :  1106.561 ms
Memfd 4 KiB    : POPULATE_READ            :    78.450 ms
Memfd 4 KiB    : POPULATE_WRITE           :   805.881 ms
Memfd 2 MiB    : Read                     :   357.116 ms
Memfd 2 MiB    : Write                    :   357.210 ms
Memfd 2 MiB    : Read/Write               :   357.606 ms
Memfd 2 MiB    : POPULATE_READ            :   356.094 ms
Memfd 2 MiB    : POPULATE_WRITE           :   356.937 ms
tmpfs          : Read                     :   137.536 ms
tmpfs          : Write                    :   954.362 ms
tmpfs          : Read/Write               :  1105.954 ms
tmpfs          : POPULATE_READ            :    80.289 ms
tmpfs          : POPULATE_WRITE           :   822.826 ms
file           : Read                     :   137.874 ms
file           : Write                    :   987.025 ms
file           : Read/Write               :  1107.439 ms
file           : POPULATE_READ            :    80.413 ms
file           : POPULATE_WRITE           :   857.622 ms
hugetlbfs      : Read                     :   355.607 ms
hugetlbfs      : Write                    :   355.729 ms
hugetlbfs      : Read/Write               :   356.127 ms
hugetlbfs      : POPULATE_READ            :   354.585 ms
hugetlbfs      : POPULATE_WRITE           :   355.138 ms
**************************************************
2 MiB MAP_SHARED:
**************************************************
Anon 4 KiB     : Read                     :     0.394 ms
Anon 4 KiB     : Write                    :     0.348 ms
Anon 4 KiB     : Read/Write               :     0.400 ms
Anon 4 KiB     : POPULATE_READ            :     0.326 ms
Anon 4 KiB     : POPULATE_WRITE           :     0.273 ms
Anon 2 MiB     : Read                     :     0.030 ms
Anon 2 MiB     : Write                    :     0.030 ms
Anon 2 MiB     : Read/Write               :     0.030 ms
Anon 2 MiB     : POPULATE_READ            :     0.030 ms
Anon 2 MiB     : POPULATE_WRITE           :     0.030 ms
Memfd 4 KiB    : Read                     :     0.412 ms
Memfd 4 KiB    : Write                    :     0.372 ms
Memfd 4 KiB    : Read/Write               :     0.419 ms
Memfd 4 KiB    : POPULATE_READ            :     0.343 ms
Memfd 4 KiB    : POPULATE_WRITE           :     0.288 ms
Memfd 4 KiB    : FALLOCATE                :     0.137 ms
Memfd 4 KiB    : FALLOCATE+Read           :     0.446 ms
Memfd 4 KiB    : FALLOCATE+Write          :     0.330 ms
Memfd 4 KiB    : FALLOCATE+Read/Write     :     0.454 ms
Memfd 4 KiB    : FALLOCATE+POPULATE_READ  :     0.379 ms
Memfd 4 KiB    : FALLOCATE+POPULATE_WRITE :     0.268 ms
Memfd 2 MiB    : Read                     :     0.030 ms
Memfd 2 MiB    : Write                    :     0.030 ms
Memfd 2 MiB    : Read/Write               :     0.030 ms
Memfd 2 MiB    : POPULATE_READ            :     0.030 ms
Memfd 2 MiB    : POPULATE_WRITE           :     0.030 ms
Memfd 2 MiB    : FALLOCATE                :     0.030 ms
Memfd 2 MiB    : FALLOCATE+Read           :     0.031 ms
Memfd 2 MiB    : FALLOCATE+Write          :     0.031 ms
Memfd 2 MiB    : FALLOCATE+Read/Write     :     0.031 ms
Memfd 2 MiB    : FALLOCATE+POPULATE_READ  :     0.030 ms
Memfd 2 MiB    : FALLOCATE+POPULATE_WRITE :     0.030 ms
tmpfs          : Read                     :     0.416 ms
tmpfs          : Write                    :     0.369 ms
tmpfs          : Read/Write               :     0.425 ms
tmpfs          : POPULATE_READ            :     0.346 ms
tmpfs          : POPULATE_WRITE           :     0.295 ms
tmpfs          : FALLOCATE                :     0.139 ms
tmpfs          : FALLOCATE+Read           :     0.447 ms
tmpfs          : FALLOCATE+Write          :     0.333 ms
tmpfs          : FALLOCATE+Read/Write     :     0.454 ms
tmpfs          : FALLOCATE+POPULATE_READ  :     0.380 ms
tmpfs          : FALLOCATE+POPULATE_WRITE :     0.272 ms
file           : Read                     :     0.191 ms
file           : Write                    :     0.511 ms
file           : Read/Write               :     0.524 ms
file           : POPULATE_READ            :     0.196 ms
file           : POPULATE_WRITE           :     0.434 ms
file           : FALLOCATE                :     0.004 ms
file           : FALLOCATE+Read           :     0.197 ms
file           : FALLOCATE+Write          :     0.554 ms
file           : FALLOCATE+Read/Write     :     0.480 ms
file           : FALLOCATE+POPULATE_READ  :     0.201 ms
file           : FALLOCATE+POPULATE_WRITE :     0.381 ms
hugetlbfs      : Read                     :     0.030 ms
hugetlbfs      : Write                    :     0.030 ms
hugetlbfs      : Read/Write               :     0.030 ms
hugetlbfs      : POPULATE_READ            :     0.030 ms
hugetlbfs      : POPULATE_WRITE           :     0.030 ms
hugetlbfs      : FALLOCATE                :     0.030 ms
hugetlbfs      : FALLOCATE+Read           :     0.031 ms
hugetlbfs      : FALLOCATE+Write          :     0.031 ms
hugetlbfs      : FALLOCATE+Read/Write     :     0.030 ms
hugetlbfs      : FALLOCATE+POPULATE_READ  :     0.030 ms
hugetlbfs      : FALLOCATE+POPULATE_WRITE :     0.030 ms
**************************************************
4096 MiB MAP_SHARED:
**************************************************
Anon 4 KiB     : Read                     :  1053.090 ms
Anon 4 KiB     : Write                    :   913.642 ms
Anon 4 KiB     : Read/Write               :  1060.350 ms
Anon 4 KiB     : POPULATE_READ            :   893.691 ms
Anon 4 KiB     : POPULATE_WRITE           :   782.885 ms
Anon 2 MiB     : Read                     :   358.553 ms
Anon 2 MiB     : Write                    :   358.419 ms
Anon 2 MiB     : Read/Write               :   357.992 ms
Anon 2 MiB     : POPULATE_READ            :   357.533 ms
Anon 2 MiB     : POPULATE_WRITE           :   357.808 ms
Memfd 4 KiB    : Read                     :  1078.144 ms
Memfd 4 KiB    : Write                    :   942.036 ms
Memfd 4 KiB    : Read/Write               :  1100.391 ms
Memfd 4 KiB    : POPULATE_READ            :   925.829 ms
Memfd 4 KiB    : POPULATE_WRITE           :   804.394 ms
Memfd 4 KiB    : FALLOCATE                :   304.632 ms
Memfd 4 KiB    : FALLOCATE+Read           :  1163.359 ms
Memfd 4 KiB    : FALLOCATE+Write          :   933.186 ms
Memfd 4 KiB    : FALLOCATE+Read/Write     :  1187.304 ms
Memfd 4 KiB    : FALLOCATE+POPULATE_READ  :  1013.660 ms
Memfd 4 KiB    : FALLOCATE+POPULATE_WRITE :   794.560 ms
Memfd 2 MiB    : Read                     :   358.131 ms
Memfd 2 MiB    : Write                    :   358.099 ms
Memfd 2 MiB    : Read/Write               :   358.250 ms
Memfd 2 MiB    : POPULATE_READ            :   357.563 ms
Memfd 2 MiB    : POPULATE_WRITE           :   357.334 ms
Memfd 2 MiB    : FALLOCATE                :   356.735 ms
Memfd 2 MiB    : FALLOCATE+Read           :   358.152 ms
Memfd 2 MiB    : FALLOCATE+Write          :   358.331 ms
Memfd 2 MiB    : FALLOCATE+Read/Write     :   358.018 ms
Memfd 2 MiB    : FALLOCATE+POPULATE_READ  :   357.286 ms
Memfd 2 MiB    : FALLOCATE+POPULATE_WRITE :   357.523 ms
tmpfs          : Read                     :  1087.265 ms
tmpfs          : Write                    :   950.840 ms
tmpfs          : Read/Write               :  1107.567 ms
tmpfs          : POPULATE_READ            :   922.605 ms
tmpfs          : POPULATE_WRITE           :   810.094 ms
tmpfs          : FALLOCATE                :   306.320 ms
tmpfs          : FALLOCATE+Read           :  1169.796 ms
tmpfs          : FALLOCATE+Write          :   933.730 ms
tmpfs          : FALLOCATE+Read/Write     :  1191.610 ms
tmpfs          : FALLOCATE+POPULATE_READ  :  1020.474 ms
tmpfs          : FALLOCATE+POPULATE_WRITE :   798.945 ms
file           : Read                     :   654.101 ms
file           : Write                    :  1259.142 ms
file           : Read/Write               :  1289.509 ms
file           : POPULATE_READ            :   661.642 ms
file           : POPULATE_WRITE           :  1106.816 ms
file           : FALLOCATE                :     1.864 ms
file           : FALLOCATE+Read           :   656.328 ms
file           : FALLOCATE+Write          :  1153.300 ms
file           : FALLOCATE+Read/Write     :  1180.613 ms
file           : FALLOCATE+POPULATE_READ  :   668.347 ms
file           : FALLOCATE+POPULATE_WRITE :   996.143 ms
hugetlbfs      : Read                     :   357.245 ms
hugetlbfs      : Write                    :   357.413 ms
hugetlbfs      : Read/Write               :   357.120 ms
hugetlbfs      : POPULATE_READ            :   356.321 ms
hugetlbfs      : POPULATE_WRITE           :   356.693 ms
hugetlbfs      : FALLOCATE                :   355.927 ms
hugetlbfs      : FALLOCATE+Read           :   357.074 ms
hugetlbfs      : FALLOCATE+Write          :   357.120 ms
hugetlbfs      : FALLOCATE+Read/Write     :   356.983 ms
hugetlbfs      : FALLOCATE+POPULATE_READ  :   356.413 ms
hugetlbfs      : FALLOCATE+POPULATE_WRITE :   356.266 ms
**************************************************

[1] https://lkml.org/lkml/2013/6/27/698

[akpm@linux-foundation.org: coding style fixes]

Link: https://lkml.kernel.org/r/20210419135443.12822-3-david@redhat.com
Signed-off-by: David Hildenbrand <david@redhat.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Jann Horn <jannh@google.com>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Rik van Riel <riel@surriel.com>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Cc: Helge Deller <deller@gmx.de>
Cc: Chris Zankel <chris@zankel.net>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Rolf Eike Beer <eike-kernel@sf-tec.de>
Cc: Ram Pai <linuxram@us.ibm.com>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-06-30 20:47:30 -07:00
Feng Tang
7858d7bca7 mm/mempolicy: don't handle MPOL_LOCAL like a fake MPOL_PREFERRED policy
MPOL_LOCAL policy has been setup as a real policy, but it is still handled
like a faked POL_PREFERRED policy with one internal MPOL_F_LOCAL flag bit
set, and there are many places having to judge the real 'prefer' or the
'local' policy, which are quite confusing.

In current code, there are 4 cases that MPOL_LOCAL are used:

1. user specifies 'local' policy

2. user specifies 'prefer' policy, but with empty nodemask

3. system 'default' policy is used

4. 'prefer' policy + valid 'preferred' node with MPOL_F_STATIC_NODES
   flag set, and when it is 'rebind' to a nodemask which doesn't contains
   the 'preferred' node, it will perform as 'local' policy

So make 'local' a real policy instead of a fake 'prefer' one, and kill
MPOL_F_LOCAL bit, which can greatly reduce the confusion for code reading.

For case 4, the logic of mpol_rebind_preferred() is confusing, as Michal
Hocko pointed out:

: I do believe that rebinding preferred policy is just bogus and it should
: be dropped altogether on the ground that a preference is a mere hint from
: userspace where to start the allocation.  Unless I am missing something
: cpusets will be always authoritative for the final placement.  The
: preferred node just acts as a starting point and it should be really
: preserved when cpusets changes.  Otherwise we have a very subtle behavior
: corner cases.

So dump all the tricky transformation between 'prefer' and 'local', and
just record the new nodemask of rebinding.

[feng.tang@intel.com: fix a problem in mpol_set_nodemask(), per Michal Hocko]
  Link: https://lkml.kernel.org/r/1622560492-1294-3-git-send-email-feng.tang@intel.com
[feng.tang@intel.com: refine code and comments of mpol_set_nodemask(), per Michal]
  Link: https://lkml.kernel.org/r/20210603081807.GE56979@shbuild999.sh.intel.com

Link: https://lkml.kernel.org/r/1622469956-82897-3-git-send-email-feng.tang@intel.com
Signed-off-by: Feng Tang <feng.tang@intel.com>
Suggested-by: Michal Hocko <mhocko@suse.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Ben Widawsky <ben.widawsky@intel.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Huang Ying <ying.huang@intel.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-06-30 20:47:29 -07:00
Axel Rasmussen
964ab0040f userfaultfd/shmem: advertise shmem minor fault support
Now that the feature is fully implemented (the faulting path hooks exist
so userspace is notified, and the ioctl to resolve such faults is
available), advertise this as a supported feature.

Link: https://lkml.kernel.org/r/20210503180737.2487560-6-axelrasmussen@google.com
Signed-off-by: Axel Rasmussen <axelrasmussen@google.com>
Acked-by: Hugh Dickins <hughd@google.com>
Acked-by: Peter Xu <peterx@redhat.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Brian Geffon <bgeffon@google.com>
Cc: "Dr . David Alan Gilbert" <dgilbert@redhat.com>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: Joe Perches <joe@perches.com>
Cc: Kirill A. Shutemov <kirill@shutemov.name>
Cc: Lokesh Gidra <lokeshgidra@google.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
Cc: Mina Almasry <almasrymina@google.com>
Cc: Oliver Upton <oupton@google.com>
Cc: Shaohua Li <shli@fb.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Wang Qing <wangqing@vivo.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-06-30 20:47:27 -07:00
Gleb Fotengauer-Malinovskiy
808e9df477 userfaultfd: uapi: fix UFFDIO_CONTINUE ioctl request definition
This ioctl request reads from uffdio_continue structure written by
userspace which justifies _IOC_WRITE flag.  It also writes back to that
structure which justifies _IOC_READ flag.

See NOTEs in include/uapi/asm-generic/ioctl.h for more information.

Fixes: f619147104 ("userfaultfd: add UFFDIO_CONTINUE ioctl")
Signed-off-by: Gleb Fotengauer-Malinovskiy <glebfm@altlinux.org>
Acked-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Axel Rasmussen <axelrasmussen@google.com>
Reviewed-by: Dmitry V. Levin <ldv@altlinux.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-06-25 10:53:26 -07:00
Linus Torvalds
9ed13a17e3 Merge tag 'net-5.13-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Pull networking fixes from Jakub Kicinski:
 "Networking fixes for 5.13-rc7, including fixes from wireless, bpf,
  bluetooth, netfilter and can.

  Current release - regressions:

   - mlxsw: spectrum_qdisc: Pass handle, not band number to find_class()
     to fix modifying offloaded qdiscs

   - lantiq: net: fix duplicated skb in rx descriptor ring

   - rtnetlink: fix regression in bridge VLAN configuration, empty info
     is not an error, bot-generated "fix" was not needed

   - libbpf: s/rx/tx/ typo on umem->rx_ring_setup_done to fix umem
     creation

  Current release - new code bugs:

   - ethtool: fix NULL pointer dereference during module EEPROM dump via
     the new netlink API

   - mlx5e: don't update netdev RQs with PTP-RQ, the special purpose
     queue should not be visible to the stack

   - mlx5e: select special PTP queue only for SKBTX_HW_TSTAMP skbs

   - mlx5e: verify dev is present in get devlink port ndo, avoid a panic

  Previous releases - regressions:

   - neighbour: allow NUD_NOARP entries to be force GCed

   - further fixes for fallout from reorg of WiFi locking (staging:
     rtl8723bs, mac80211, cfg80211)

   - skbuff: fix incorrect msg_zerocopy copy notifications

   - mac80211: fix NULL ptr deref for injected rate info

   - Revert "net/mlx5: Arm only EQs with EQEs" it may cause missed IRQs

  Previous releases - always broken:

   - bpf: more speculative execution fixes

   - netfilter: nft_fib_ipv6: skip ipv6 packets from any to link-local

   - udp: fix race between close() and udp_abort() resulting in a panic

   - fix out of bounds when parsing TCP options before packets are
     validated (in netfilter: synproxy, tc: sch_cake and mptcp)

   - mptcp: improve operation under memory pressure, add missing
     wake-ups

   - mptcp: fix double-lock/soft lookup in subflow_error_report()

   - bridge: fix races (null pointer deref and UAF) in vlan tunnel
     egress

   - ena: fix DMA mapping function issues in XDP

   - rds: fix memory leak in rds_recvmsg

  Misc:

   - vrf: allow larger MTUs

   - icmp: don't send out ICMP messages with a source address of 0.0.0.0

   - cdc_ncm: switch to eth%d interface naming"

* tag 'net-5.13-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (139 commits)
  net: ethernet: fix potential use-after-free in ec_bhf_remove
  selftests/net: Add icmp.sh for testing ICMP dummy address responses
  icmp: don't send out ICMP messages with a source address of 0.0.0.0
  net: ll_temac: Avoid ndo_start_xmit returning NETDEV_TX_BUSY
  net: ll_temac: Fix TX BD buffer overwrite
  net: ll_temac: Add memory-barriers for TX BD access
  net: ll_temac: Make sure to free skb when it is completely used
  MAINTAINERS: add Guvenc as SMC maintainer
  bnxt_en: Call bnxt_ethtool_free() in bnxt_init_one() error path
  bnxt_en: Fix TQM fastpath ring backing store computation
  bnxt_en: Rediscover PHY capabilities after firmware reset
  cxgb4: fix wrong shift.
  mac80211: handle various extensible elements correctly
  mac80211: reset profile_periodicity/ema_ap
  cfg80211: avoid double free of PMSR request
  cfg80211: make certificate generation more robust
  mac80211: minstrel_ht: fix sample time check
  net: qed: Fix memcpy() overflow of qed_dcbx_params()
  net: cdc_eem: fix tx fixup skb leak
  net: hamradio: fix memory leak in mkiss_close
  ...
2021-06-18 18:55:29 -07:00
Toke Høiland-Jørgensen
3218274773 icmp: don't send out ICMP messages with a source address of 0.0.0.0
When constructing ICMP response messages, the kernel will try to pick a
suitable source address for the outgoing packet. However, if no IPv4
addresses are configured on the system at all, this will fail and we end up
producing an ICMP message with a source address of 0.0.0.0. This can happen
on a box routing IPv4 traffic via v6 nexthops, for instance.

Since 0.0.0.0 is not generally routable on the internet, there's a good
chance that such ICMP messages will never make it back to the sender of the
original packet that the ICMP message was sent in response to. This, in
turn, can create connectivity and PMTUd problems for senders. Fortunately,
RFC7600 reserves a dummy address to be used as a source for ICMP
messages (192.0.0.8/32), so let's teach the kernel to substitute that
address as a last resort if the regular source address selection procedure
fails.

Below is a quick example reproducing this issue with network namespaces:

ip netns add ns0
ip l add type veth peer netns ns0
ip l set dev veth0 up
ip a add 10.0.0.1/24 dev veth0
ip a add fc00:dead:cafe:42::1/64 dev veth0
ip r add 10.1.0.0/24 via inet6 fc00:dead:cafe:42::2
ip -n ns0 l set dev veth0 up
ip -n ns0 a add fc00:dead:cafe:42::2/64 dev veth0
ip -n ns0 r add 10.0.0.0/24 via inet6 fc00:dead:cafe:42::1
ip netns exec ns0 sysctl -w net.ipv4.icmp_ratelimit=0
ip netns exec ns0 sysctl -w net.ipv4.ip_forward=1
tcpdump -tpni veth0 -c 2 icmp &
ping -w 1 10.1.0.1 > /dev/null
tcpdump: verbose output suppressed, use -v[v]... for full protocol decode
listening on veth0, link-type EN10MB (Ethernet), snapshot length 262144 bytes
IP 10.0.0.1 > 10.1.0.1: ICMP echo request, id 29, seq 1, length 64
IP 0.0.0.0 > 10.0.0.1: ICMP net 10.1.0.1 unreachable, length 92
2 packets captured
2 packets received by filter
0 packets dropped by kernel

With this patch the above capture changes to:
IP 10.0.0.1 > 10.1.0.1: ICMP echo request, id 31127, seq 1, length 64
IP 192.0.0.8 > 10.0.0.1: ICMP net 10.1.0.1 unreachable, length 92

Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Reported-by: Juliusz Chroboczek <jch@irif.fr>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-18 12:13:24 -07:00
Linus Torvalds
39519f6a56 Merge tag 'fixes_for_v5.13-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs
Pull quota and fanotify fixes from Jan Kara:
 "A fixup finishing disabling of quotactl_path() syscall (I've missed
  archs using different way to declare syscalls) and a fix of an fd leak
  in error handling path of fanotify"

* tag 'fixes_for_v5.13-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs:
  quota: finish disable quotactl_path syscall
  fanotify: fix copy_event_to_user() fid error clean up
2021-06-17 09:49:48 -07:00
Marcin Juszkiewicz
8b1462b67f quota: finish disable quotactl_path syscall
In commit 5b9fedb31e ("quota: Disable quotactl_path syscall") Jan Kara
disabled quotactl_path syscall on several architectures.

This commit disables it on all architectures using unified list of
system calls:

- arm64
- arc
- csky
- h8300
- hexagon
- nds32
- nios2
- openrisc
- riscv (32/64)

CC: Jan Kara <jack@suse.cz>
CC: Christian Brauner <christian.brauner@ubuntu.com>
CC: Sascha Hauer <s.hauer@pengutronix.de>
Link: https://lore.kernel.org/lkml/20210512153621.n5u43jsytbik4yze@wittgenstein
Link: https://lore.kernel.org/r/20210614153712.313707-1-marcin@juszkiewicz.com.pl
Fixes: 5b9fedb31e ("quota: Disable quotactl_path syscall")
Acked-by: Christian Brauner <christian.brauner@ubuntu.com>
Signed-off-by: Marcin Juszkiewicz <marcin@juszkiewicz.com.pl>
Signed-off-by: Jan Kara <jack@suse.cz>
2021-06-15 11:22:45 +02:00
Linus Torvalds
b2568eeb96 Merge tag 'io_uring-5.13-2021-06-12' of git://git.kernel.dk/linux-block
Pull io_uring fixes from Jens Axboe:
 "Just an API change for the registration changes that went into this
  release. Better to get it sorted out now than before it's too late"

* tag 'io_uring-5.13-2021-06-12' of git://git.kernel.dk/linux-block:
  io_uring: add feature flag for rsrc tags
  io_uring: change registration/upd/rsrc tagging ABI
2021-06-12 11:53:20 -07:00
Pavel Begunkov
9690557e22 io_uring: add feature flag for rsrc tags
Add IORING_FEAT_RSRC_TAGS indicating that io_uring supports a bunch of
new IORING_REGISTER operations, in particular
IORING_REGISTER_[FILES[,UPDATE]2,BUFFERS[2,UPDATE]] that support rsrc
tagging, and also indicating implemented dynamic fixed buffer updates.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/9b995d4045b6c6b4ab7510ca124fd25ac2203af7.1623339162.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-06-10 16:33:51 -06:00
Pavel Begunkov
992da01aa9 io_uring: change registration/upd/rsrc tagging ABI
There are ABI moments about recently added rsrc registration/update and
tagging that might become a nuisance in the future. First,
IORING_REGISTER_RSRC[_UPD] hide different types of resources under it,
so breaks fine control over them by restrictions. It works for now, but
once those are wanted under restrictions it would require a rework.

It was also inconvenient trying to fit a new resource not supporting
all the features (e.g. dynamic update) into the interface, so better
to return to IORING_REGISTER_* top level dispatching.

Second, register/update were considered to accept a type of resource,
however that's not a good idea because there might be several ways of
registration of a single resource type, e.g. we may want to add
non-contig buffers or anything more exquisite as dma mapped memory.
So, remove IORING_RSRC_[FILE,BUFFER] out of the ABI, and place them
internally for now to limit changes.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/9b554897a7c17ad6e3becc48dfed2f7af9f423d5.1623339162.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-06-10 16:33:51 -06:00
Linus Torvalds
9d32fa5d74 Merge tag 'net-5.13-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Pull networking fixes from Jakub Kicinski:
 "Networking fixes, including fixes from bpf, wireless, netfilter and
  wireguard trees.

  The bpf vs lockdown+audit fix is the most notable.

  Things haven't slowed down just yet, both in terms of regressions in
  current release and largish fixes for older code, but we usually see a
  slowdown only after -rc5.

  Current release - regressions:

   - virtio-net: fix page faults and crashes when XDP is enabled

   - mlx5e: fix HW timestamping with CQE compression, and make sure they
     are only allowed to coexist with capable devices

   - stmmac:
      - fix kernel panic due to NULL pointer dereference of
        mdio_bus_data
      - fix double clk unprepare when no PHY device is connected

  Current release - new code bugs:

   - mt76: a few fixes for the recent MT7921 devices and runtime power
     management

  Previous releases - regressions:

   - ice:
      - track AF_XDP ZC enabled queues in bitmap to fix copy mode Tx
      - fix allowing VF to request more/less queues via virtchnl
      - correct supported and advertised autoneg by using PHY
        capabilities
      - allow all LLDP packets from PF to Tx

   - kbuild: quote OBJCOPY var to avoid a pahole call break the build

  Previous releases - always broken:

   - bpf, lockdown, audit: fix buggy SELinux lockdown permission checks

   - mt76: address the recent FragAttack vulnerabilities not covered by
     generic fixes

   - ipv6: fix KASAN: slab-out-of-bounds Read in
     fib6_nh_flush_exceptions

   - Bluetooth:
      - fix the erroneous flush_work() order, to avoid double free
      - use correct lock to prevent UAF of hdev object

   - nfc: fix NULL ptr dereference in llcp_sock_getname() after failed
     connect

   - ieee802154: multiple fixes to error checking and return values

   - igb: fix XDP with PTP enabled

   - intel: add correct exception tracing for XDP

   - tls: fix use-after-free when TLS offload device goes down and back
     up

   - ipvs: ignore IP_VS_SVC_F_HASHED flag when adding service

   - netfilter: nft_ct: skip expectations for confirmed conntrack

   - mptcp: fix falling back to TCP in presence of out of order packets
     early in connection lifetime

   - wireguard: switch from O(n) to a O(1) algorithm for maintaining
     peers, fixing stalls and a large memory leak in the process

  Misc:

   - devlink: correct VIRTUAL port to not have phys_port attributes

   - Bluetooth: fix VIRTIO_ID_BT assigned number

   - net: return the correct errno code ENOBUF -> ENOMEM

   - wireguard:
      - peer: allocate in kmem_cache saving 25% on peer memory
      - do not use -O3"

* tag 'net-5.13-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (91 commits)
  cxgb4: avoid link re-train during TC-MQPRIO configuration
  sch_htb: fix refcount leak in htb_parent_to_leaf_offload
  wireguard: allowedips: free empty intermediate nodes when removing single node
  wireguard: allowedips: allocate nodes in kmem_cache
  wireguard: allowedips: remove nodes in O(1)
  wireguard: allowedips: initialize list head in selftest
  wireguard: peer: allocate in kmem_cache
  wireguard: use synchronize_net rather than synchronize_rcu
  wireguard: do not use -O3
  wireguard: selftests: make sure rp_filter is disabled on vethc
  wireguard: selftests: remove old conntrack kconfig value
  virtchnl: Add missing padding to virtchnl_proto_hdrs
  ice: Allow all LLDP packets from PF to Tx
  ice: report supported and advertised autoneg using PHY capabilities
  ice: handle the VF VSI rebuild failure
  ice: Fix VFR issues for AVF drivers that expect ATQLEN cleared
  ice: Fix allowing VF to request more/less queues via virtchnl
  virtio-net: fix for skb_over_panic inside big mode
  ipv6: Fix KASAN: slab-out-of-bounds Read in fib6_nh_flush_exceptions
  fib: Return the correct errno code
  ...
2021-06-04 18:25:39 -07:00
David S. Miller
579028dec1 Merge tag 'for-net-2021-06-03' of git://git.kernel.org/pub/scm/linux/kernel/git/bluetooth/bluetooth
bluetooth pull request for net:

 - Fixes UAF and CVE-2021-3564
 - Fix VIRTIO_ID_BT to use an unassigned ID
 - Fix firmware loading on some Intel Controllers

Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-03 15:32:21 -07:00
Marcel Holtmann
a83d958504 Bluetooth: Fix VIRTIO_ID_BT assigned number
It turned out that the VIRTIO_ID_* are not assigned in the virtio_ids.h
file in the upstream kernel. Picking the next free one was wrong and
there is a process that has been followed now.

See https://github.com/oasis-tcs/virtio-spec/issues/108 for details.

Fixes: afd2daa26c ("Bluetooth: Add support for virtio transport driver")
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
2021-06-03 14:01:55 -07:00
Linus Torvalds
231bc53906 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/hid/hid
Pull HID fixes from Jiri Kosina:

 - memory leak fix in usbhid from Anirudh Rayabharam

 - additions for a few new recognized generic key IDs from Dmitry
   Torokhov

 - Asus T101HA and Dell K15A quirks from Hans de Goede

 - memory leak fix in amd_sfh from Basavaraj Natikar

 - Win8 compatibility and Stylus fixes in multitouch driver from
   Ahelenia Ziemiańska

 - NULL pointer dereference fix in hid-magicmouse from Johan Hovold

 - assorted other small fixes and device ID additions

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/hid/hid: (33 commits)
  HID: asus: Cleanup Asus T101HA keyboard-dock handling
  HID: magicmouse: fix NULL-deref on disconnect
  HID: intel-ish-hid: ipc: Add Alder Lake device IDs
  HID: i2c-hid: fix format string mismatch
  HID: amd_sfh: Fix memory leak in amd_sfh_work
  HID: amd_sfh: Use devm_kzalloc() instead of kzalloc()
  HID: ft260: improve error handling of ft260_hid_feature_report_get()
  HID: magicmouse: fix crash when disconnecting Magic Trackpad 2
  HID: gt683r: add missing MODULE_DEVICE_TABLE
  HID: pidff: fix error return code in hid_pidff_init()
  HID: logitech-hidpp: initialize level variable
  HID: multitouch: Disable event reporting on suspend on the Asus T101HA touchpad
  HID: core: Remove extraneous empty line before EXPORT_SYMBOL_GPL(hid_check_keys_pressed)
  HID: hid-sensor-custom: Process failure of sensor_hub_set_feature()
  HID: i2c-hid: Skip ELAN power-on command after reset
  HID: usbhid: fix info leak in hid_submit_ctrl
  HID: Add BUS_VIRTUAL to hid_connect logging
  HID: multitouch: set Stylus suffix for Stylus-application devices, too
  HID: multitouch: require Finger field to mark Win8 reports as MT
  HID: remove the unnecessary redefinition of a macro
  ...
2021-06-01 17:26:06 -10:00
Linus Torvalds
224478289c Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull KVM fixes from Paolo Bonzini:
 "ARM fixes:

   - Another state update on exit to userspace fix

   - Prevent the creation of mixed 32/64 VMs

   - Fix regression with irqbypass not restarting the guest on failed
     connect

   - Fix regression with debug register decoding resulting in
     overlapping access

   - Commit exception state on exit to usrspace

   - Fix the MMU notifier return values

   - Add missing 'static' qualifiers in the new host stage-2 code

  x86 fixes:

   - fix guest missed wakeup with assigned devices

   - fix WARN reported by syzkaller

   - do not use BIT() in UAPI headers

   - make the kvm_amd.avic parameter bool

  PPC fixes:

   - make halt polling heuristics consistent with other architectures

  selftests:

   - various fixes

   - new performance selftest memslot_perf_test

   - test UFFD minor faults in demand_paging_test"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (44 commits)
  selftests: kvm: fix overlapping addresses in memslot_perf_test
  KVM: X86: Kill off ctxt->ud
  KVM: X86: Fix warning caused by stale emulation context
  KVM: X86: Use kvm_get_linear_rip() in single-step and #DB/#BP interception
  KVM: x86/mmu: Fix comment mentioning skip_4k
  KVM: VMX: update vcpu posted-interrupt descriptor when assigning device
  KVM: rename KVM_REQ_PENDING_TIMER to KVM_REQ_UNBLOCK
  KVM: x86: add start_assignment hook to kvm_x86_ops
  KVM: LAPIC: Narrow the timer latency between wait_lapic_expire and world switch
  selftests: kvm: do only 1 memslot_perf_test run by default
  KVM: X86: Use _BITUL() macro in UAPI headers
  KVM: selftests: add shared hugetlbfs backing source type
  KVM: selftests: allow using UFFD minor faults for demand paging
  KVM: selftests: create alias mappings when using shared memory
  KVM: selftests: add shmem backing source type
  KVM: selftests: refactor vm_mem_backing_src_type flags
  KVM: selftests: allow different backing source types
  KVM: selftests: compute correct demand paging size
  KVM: selftests: simplify setup_demand_paging error handling
  KVM: selftests: Print a message if /dev/kvm is missing
  ...
2021-05-29 06:02:25 -10:00
Joe Richey
fb1070d18e KVM: X86: Use _BITUL() macro in UAPI headers
Replace BIT() in KVM's UPAI header with _BITUL(). BIT() is not defined
in the UAPI headers and its usage may cause userspace build errors.

Fixes: fb04a1eddb ("KVM: X86: Implement ring-based dirty memory tracking")
Signed-off-by: Joe Richey <joerichey@google.com>
Message-Id: <20210521085849.37676-3-joerichey94@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-05-27 07:45:57 -04:00
Linus Torvalds
a0e31f3a38 Merge branch 'for-v5.13-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace
Pull siginfo fix from Eric Biederman:
 "During the merge window an issue with si_perf and the siginfo ABI came
  up. The alpha and sparc siginfo structure layout had changed with the
  addition of SIGTRAP TRAP_PERF and the new field si_perf.

  The reason only alpha and sparc were affected is that they are the
  only architectures that use si_trapno.

  Looking deeper it was discovered that si_trapno is used for only a few
  select signals on alpha and sparc, and that none of the other
  _sigfault fields past si_addr are used at all. Which means technically
  no regression on alpha and sparc.

  While the alignment concerns might be dismissed the abuse of si_errno
  by SIGTRAP TRAP_PERF does have the potential to cause regressions in
  existing userspace.

  While we still have time before userspace starts using and depending
  on the new definition siginfo for SIGTRAP TRAP_PERF this set of
  changes cleans up siginfo_t.

   - The si_trapno field is demoted from magic alpha and sparc status
     and made an ordinary union member of the _sigfault member of
     siginfo_t. Without moving it of course.

   - si_perf is replaced with si_perf_data and si_perf_type ending the
     abuse of si_errno.

   - Unnecessary additions to signalfd_siginfo are removed"

* 'for-v5.13-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace:
  signalfd: Remove SIL_PERF_EVENT fields from signalfd_siginfo
  signal: Deliver all of the siginfo perf data in _perf
  signal: Factor force_sig_perf out of perf_sigtrap
  signal: Implement SIL_FAULT_TRAPNO
  siginfo: Move si_trapno inside the union inside _si_fault
2021-05-21 06:12:52 -10:00
Linus Torvalds
50f09a3dd5 Merge tag 'char-misc-5.13-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc
Pull char/misc driver fixes from Greg KH:
 "Here is a big set of char/misc/other driver fixes for 5.13-rc3.

  The majority here is the fallout of the umn.edu re-review of all prior
  submissions. That resulted in a bunch of reverts along with the
  "correct" changes made, such that there is no regression of any of the
  potential fixes that were made by those individuals. I would like to
  thank the over 80 different developers who helped with the review and
  fixes for this mess.

  Other than that, there's a few habanna driver fixes for reported
  issues, and some dyndbg fixes for reported problems.

  All of these have been in linux-next for a while with no reported
  problems"

* tag 'char-misc-5.13-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (82 commits)
  misc: eeprom: at24: check suspend status before disable regulator
  uio_hv_generic: Fix another memory leak in error handling paths
  uio_hv_generic: Fix a memory leak in error handling paths
  uio/uio_pci_generic: fix return value changed in refactoring
  Revert "Revert "ALSA: usx2y: Fix potential NULL pointer dereference""
  dyndbg: drop uninformative vpr_info
  dyndbg: avoid calling dyndbg_emit_prefix when it has no work
  binder: Return EFAULT if we fail BINDER_ENABLE_ONEWAY_SPAM_DETECTION
  cdrom: gdrom: initialize global variable at init time
  brcmfmac: properly check for bus register errors
  Revert "brcmfmac: add a check for the status of usb_register"
  video: imsttfb: check for ioremap() failures
  Revert "video: imsttfb: fix potential NULL pointer dereferences"
  net: liquidio: Add missing null pointer checks
  Revert "net: liquidio: fix a NULL pointer dereference"
  media: gspca: properly check for errors in po1030_probe()
  Revert "media: gspca: Check the return value of write_bridge for timeout"
  media: gspca: mt9m111: Check write_bridge for timeout
  Revert "media: gspca: mt9m111: Check write_bridge for timeout"
  media: dvb: Add check on sp8870_readreg return
  ...
2021-05-20 06:31:52 -10:00
Eric W. Biederman
922e301304 signalfd: Remove SIL_PERF_EVENT fields from signalfd_siginfo
With the addition of ssi_perf_data and ssi_perf_type struct signalfd_siginfo
is dangerously close to running out of space.  All that remains is just
enough space for two additional 64bit fields.  A practice of adding all
possible siginfo_t fields into struct singalfd_siginfo can not be supported
as adding the missing fields ssi_lower, ssi_upper, and ssi_pkey would
require two 64bit fields and one 32bit fields.  In practice the fields
ssi_perf_data and ssi_perf_type can never be used by signalfd as the signal
that generates them always delivers them synchronously to the thread that
triggers them.

Therefore until someone actually needs the fields ssi_perf_data and
ssi_perf_type in signalfd_siginfo remove them.  This leaves a bit more room
for future expansion.

v1: https://lkml.kernel.org/r/20210503203814.25487-12-ebiederm@xmission.com
v2: https://lkml.kernel.org/r/20210505141101.11519-12-ebiederm@xmission.com
Link: https://lkml.kernel.org/r/20210517195748.8880-5-ebiederm@xmission.com
Reviewed-by: Marco Elver <elver@google.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2021-05-18 16:20:54 -05:00
Eric W. Biederman
0683b53197 signal: Deliver all of the siginfo perf data in _perf
Don't abuse si_errno and deliver all of the perf data in _perf member
of siginfo_t.

Note: The data field in the perf data structures in a u64 to allow a
pointer to be encoded without needed to implement a 32bit and 64bit
version of the same structure.  There already exists a 32bit and 64bit
versions siginfo_t, and the 32bit version can not include a 64bit
member as it only has 32bit alignment.  So unsigned long is used in
siginfo_t instead of a u64 as unsigned long can encode a pointer on
all architectures linux supports.

v1: https://lkml.kernel.org/r/m11rarqqx2.fsf_-_@fess.ebiederm.org
v2: https://lkml.kernel.org/r/20210503203814.25487-10-ebiederm@xmission.com
v3: https://lkml.kernel.org/r/20210505141101.11519-11-ebiederm@xmission.com
Link: https://lkml.kernel.org/r/20210517195748.8880-4-ebiederm@xmission.com
Reviewed-by: Marco Elver <elver@google.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2021-05-18 16:20:54 -05:00
Eric W. Biederman
add0b32ef9 siginfo: Move si_trapno inside the union inside _si_fault
It turns out that linux uses si_trapno very sparingly, and as such it
can be considered extra information for a very narrow selection of
signals, rather than information that is present with every fault
reported in siginfo.

As such move si_trapno inside the union inside of _si_fault.  This
results in no change in placement, and makes it eaiser
to extend _si_fault in the future as this reduces the number of
special cases.  In particular with si_trapno included in the union it
is no longer a concern that the union must be pointer aligned on most
architectures because the union follows immediately after si_addr
which is a pointer.

This change results in a difference in siginfo field placement on
sparc and alpha for the fields si_addr_lsb, si_lower, si_upper,
si_pkey, and si_perf.  These architectures do not implement the
signals that would use si_addr_lsb, si_lower, si_upper, si_pkey, and
si_perf.  Further these architecture have not yet implemented the
userspace that would use si_perf.

The point of this change is in fact to correct these placement issues
before sparc or alpha grow userspace that cares.  This change was
discussed[1] and the agreement is that this change is currently safe.

[1]: https://lkml.kernel.org/r/CAK8P3a0+uKYwL1NhY6Hvtieghba2hKYGD6hcKx5n8=4Gtt+pHA@mail.gmail.com
Acked-by: Marco Elver <elver@google.com>
v1: https://lkml.kernel.org/r/m1tunns7yf.fsf_-_@fess.ebiederm.org
v2: https://lkml.kernel.org/r/20210505141101.11519-5-ebiederm@xmission.com
Link: https://lkml.kernel.org/r/20210517195748.8880-1-ebiederm@xmission.com
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2021-05-18 16:17:03 -05:00
Linus Torvalds
8f4ae0f68c Merge tag 'block-5.13-2021-05-14' of git://git.kernel.dk/linux-block
Pull block fixes from Jens Axboe:

 - Fix for shared tag set exit (Bart)

 - Correct ioctl range for zoned ioctls (Damien)

 - Removed dead/unused function (Lin)

 - Fix perf regression for shared tags (Ming)

 - Fix out-of-bounds issue with kyber and preemption (Omar)

 - BFQ merge fix (Paolo)

 - Two error handling fixes for nbd (Sun)

 - Fix weight update in blk-iocost (Tejun)

 - NVMe pull request (Christoph):
      - correct the check for using the inline bio in nvmet (Chaitanya
        Kulkarni)
      - demote unsupported command warnings (Chaitanya Kulkarni)
      - fix corruption due to double initializing ANA state (me, Hou Pu)
      - reset ns->file when open fails (Daniel Wagner)
      - fix a NULL deref when SEND is completed with error in nvmet-rdma
        (Michal Kalderon)

 - Fix kernel-doc warning (Bart)

* tag 'block-5.13-2021-05-14' of git://git.kernel.dk/linux-block:
  block/partitions/efi.c: Fix the efi_partition() kernel-doc header
  blk-mq: Swap two calls in blk_mq_exit_queue()
  blk-mq: plug request for shared sbitmap
  nvmet: use new ana_log_size instead the old one
  nvmet: seset ns->file when open fails
  nbd: share nbd_put and return by goto put_nbd
  nbd: Fix NULL pointer in flush_workqueue
  blkdev.h: remove unused codes blk_account_rq
  block, bfq: avoid circular stable merges
  blk-iocost: fix weight updates of inner active iocgs
  nvmet: demote fabrics cmd parse err msg to debug
  nvmet: use helper to remove the duplicate code
  nvmet: demote discovery cmd parse err msg to debug
  nvmet-rdma: Fix NULL deref when SEND is completed with error
  nvmet: fix inline bio check for passthru
  nvmet: fix inline bio check for bdev-ns
  nvme-multipath: fix double initialization of ANA state
  kyber: fix out of bounds access when preempted
  block: uapi: fix comment about block device ioctl
2021-05-15 08:52:30 -07:00
Damien Le Moal
63c8af5687 block: uapi: fix comment about block device ioctl
Fix the comment mentioning ioctl command range used for zoned block
devices to reflect the range of commands actually implemented.

Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>
Link: https://lore.kernel.org/r/20210509234806.3000-1-damien.lemoal@wdc.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-05-10 09:26:18 -06:00
Greg Kroah-Hartman
ba2b062ffa Merge tag 'misc-habanalabs-fixes-2021-05-08' of https://git.kernel.org/pub/scm/linux/kernel/git/ogabbay/linux into char-misc-linus
Oded writes:

This tag contains the following fixes for 5.13-rc2:

- Expose PLL information per ASIC. This also fixes some casting warnings.
- Skip reading further firmware errors in case PCI link is down.
- Security firmware error should be handled as error and not warning.
- Allow user to ignore firmware errors.
- Fix bug in timeout calculation when waiting for interrupt of CS.
- Fix bug of potential use-after-free.

* tag 'misc-habanalabs-fixes-2021-05-08' of https://git.kernel.org/pub/scm/linux/kernel/git/ogabbay/linux:
  habanalabs/gaudi: Fix a potential use after free in gaudi_memset_device_memory
  habanalabs: wait for interrupt wrong timeout calculation
  habanalabs: ignore f/w status error
  habanalabs: change error level of security not ready
  habanalabs: skip reading f/w errors on bad status
  habanalabs: expose ASIC specific PLL index
2021-05-10 16:30:03 +02:00