Commit Graph

824686 Commits

Author SHA1 Message Date
Josef Bacik
a75d4c3337 filemap: kill page_cache_read usage in filemap_fault
Patch series "drop the mmap_sem when doing IO in the fault path", v6.

Now that we have proper isolation in place with cgroups2 we have started
going through and fixing the various priority inversions.  Most are all
gone now, but this one is sort of weird since it's not necessarily a
priority inversion that happens within the kernel, but rather because of
something userspace does.

We have giant applications that we want to protect, and parts of these
giant applications do things like watch the system state to determine how
healthy the box is for load balancing and such.  This involves running
'ps' or other such utilities.  These utilities will often walk
/proc/<pid>/whatever, and these files can sometimes need to
down_read(&task->mmap_sem).  Not usually a big deal, but we noticed when
we are stress testing that sometimes our protected application has latency
spikes trying to get the mmap_sem for tasks that are in lower priority
cgroups.

This is because any down_write() on a semaphore essentially turns it into
a mutex, so even if we currently have it held for reading, any new readers
will not be allowed on to keep from starving the writer.  This is fine,
except a lower priority task could be stuck doing IO because it has been
throttled to the point that its IO is taking much longer than normal.  But
because a higher priority group depends on this completing it is now stuck
behind lower priority work.

In order to avoid this particular priority inversion we want to use the
existing retry mechanism to stop from holding the mmap_sem at all if we
are going to do IO.  This already exists in the read case sort of, but
needed to be extended for more than just grabbing the page lock.  With
io.latency we throttle at submit_bio() time, so the readahead stuff can
block and even page_cache_read can block, so all these paths need to have
the mmap_sem dropped.

The other big thing is ->page_mkwrite.  btrfs is particularly shitty here
because we have to reserve space for the dirty page, which can be a very
expensive operation.  We use the same retry method as the read path, and
simply cache the page and verify the page is still setup properly the next
pass through ->page_mkwrite().

I've tested these patches with xfstests and there are no regressions.

This patch (of 3):

If we do not have a page at filemap_fault time we'll do this weird forced
page_cache_read thing to populate the page, and then drop it again and
loop around and find it.  This makes for 2 ways we can read a page in
filemap_fault, and it's not really needed.  Instead add a FGP_FOR_MMAP
flag so that pagecache_get_page() will return a unlocked page that's in
pagecache.  Then use the normal page locking and readpage logic already in
filemap_fault.  This simplifies the no page in page cache case
significantly.

[akpm@linux-foundation.org: fix comment text]
[josef@toxicpanda.com: don't unlock null page in FGP_FOR_MMAP case]
  Link: http://lkml.kernel.org/r/20190312201742.22935-1-josef@toxicpanda.com
Link: http://lkml.kernel.org/r/20181211173801.29535-2-josef@toxicpanda.com
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: "Kirill A. Shutemov" <kirill@shutemov.name>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-03-15 11:21:25 -07:00
Paolo Bonzini
c7a0e83cb6 Third PPC KVM update for 5.1
- Tell userspace about whether a particular hardware workaround for
   one of the Spectre vulnerabilities is available, so that userspace
   can inform the guest.
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Merge tag 'kvm-ppc-next-5.1-3' of git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc into HEAD

Third PPC KVM update for 5.1

- Tell userspace about whether a particular hardware workaround for
  one of the Spectre vulnerabilities is available, so that userspace
  can inform the guest.
2019-03-15 19:16:51 +01:00
Sean Christopherson
4633323648 MAINTAINERS: Add KVM selftests to existing KVM entry
It's safe to assume Paolo and Radim are maintaining the KVM selftests
given that the vast majority of commits have their SOBs.  Play nice
with get_maintainers and make it official.

Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-03-15 19:16:48 +01:00
Ben Gardon
92da008fa2 Revert "KVM/MMU: Flush tlb directly in the kvm_zap_gfn_range()"
This reverts commit 71883a62fc.

The above commit contains an optimization to kvm_zap_gfn_range which
uses gfn-limited TLB flushes, if enabled. If using these limited flushes,
kvm_zap_gfn_range passes lock_flush_tlb=false to slot_handle_level_range
which creates a race when the function unlocks to call cond_resched.
See an example of this race below:

CPU 0                   CPU 1                           CPU 3
// zap_direct_gfn_range
mmu_lock()
// *ptep == pte_1
*ptep = 0
if (lock_flush_tlb)
        flush_tlbs()
mmu_unlock()
                        // In invalidate range
                        // MMU notifier
                        mmu_lock()
                        if (pte != 0)
                                *ptep = 0
                                flush = true
                        if (flush)
                                flush_remote_tlbs()
                        mmu_unlock()
                        return
                        // Host MM reallocates
                        // page previously
                        // backing guest memory.
                                                        // Guest accesses
                                                        // invalid page
                                                        // through pte_1
                                                        // in its TLB!!

Tested: Ran all kvm-unit-tests on a Intel Haswell machine with and
	without this patch. The patch introduced no new failures.

Signed-off-by: Ben Gardon <bgardon@google.com>
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-03-15 19:16:45 +01:00
Hannes Reinecke
52eaa798f4 scsi: ia64: simscsi: use request tag instead of serial_number
Use the request tag for logging instead of the scsi command serial
number.

Signed-off-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
[jejb: fix commit oneliner]
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2019-03-15 10:53:41 -07:00
Trond Myklebust
5e3863fd59 SUNRPC: Remove redundant check for the reply length in call_decode()
Now that we're using the xdr_stream functions to decode the header,
the test for the minimum reply length is redundant.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2019-03-15 13:11:36 -04:00
Trond Myklebust
928d42f7d8 SUNRPC: Handle the SYSTEM_ERR rpc error
Handle the SYSTEM_ERR rpc error by retrying the RPC call as if it
were a garbage argument.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2019-03-15 13:11:02 -04:00
Trond Myklebust
eb90a16e90 SUNRPC: rpc_decode_header() must always return a non-zero value on error
Ensure that when the "garbage args" case falls through, we do set
an error of EIO.

Fixes: a0584ee9ae ("SUNRPC: Use struct xdr_stream when decoding...")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2019-03-15 13:08:59 -04:00
Trond Myklebust
27adc78592 SUNRPC: Use the ENOTCONN error on socket disconnect
When the socket is closed, we currently send an EAGAIN error to all
pending requests in order to ask them to retransmit. Use ENOTCONN
instead, to ensure that they try to reconnect before attempting to
transmit.
This also helps SOFTCONN tasks to behave correctly in this
situation.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2019-03-15 13:08:20 -04:00
Trond Myklebust
513149607d SUNRPC: Fix the minimal size for reply buffer allocation
We must at minimum allocate enough memory to be able to see any auth
errors in the reply from the server.

Fixes: 2c94b8eca1 ("SUNRPC: Use au_rslack when computing reply...")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2019-03-15 13:06:35 -04:00
Trond Myklebust
9734ad57b0 SUNRPC: Fix a client regression when handling oversized replies
If the server sends a reply that is larger than the pre-allocated
buffer, then the current code may fail to register how much of
the stream that it has finished reading. This again can lead to
hangs.

Fixes: e92053a52e ("SUNRPC: Handle zero length fragments correctly")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2019-03-15 13:06:21 -04:00
Aaron Ma
bb6bccba39 iommu/amd: Fix NULL dereference bug in match_hid_uid
Add a non-NULL check to fix potential NULL pointer dereference
Cleanup code to call function once.

Signed-off-by: Aaron Ma <aaron.ma@canonical.com>
Fixes: 2bf9a0a127 ('iommu/amd: Add iommu support for ACPI HID devices')
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2019-03-15 16:22:05 +01:00
Russell King
4c2741ac5e Merge branches 'fixes', 'misc' and 'smp-hotplug' into for-next 2019-03-15 15:12:56 +00:00
David Hildenbrand
0266def913 xen/balloon: Fix mapping PG_offline pages to user space
The XEN balloon driver - in contrast to other balloon drivers - allows
to map some inflated pages to user space. Such pages are allocated via
alloc_xenballooned_pages() and freed via free_xenballooned_pages().
The pfn space of these allocated pages is used to map other things
by the hypervisor using hypercalls.

Pages marked with PG_offline must never be mapped to user space (as
this page type uses the mapcount field of struct pages).

So what we can do is, clear/set PG_offline when allocating/freeing an
inflated pages. This way, most inflated pages can be excluded by
dumping tools and the "reused for other purpose" balloon pages are
correctly not marked as PG_offline.

Fixes: 77c4adf6a6 (xen/balloon: mark inflated pages PG_offline)
Reported-by: Julien Grall <julien.grall@arm.com>
Tested-by: Julien Grall <julien.grall@arm.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
2019-03-15 15:35:35 +01:00
Peter Zijlstra
f764c58b7f perf/x86: Fixup typo in stub functions
Guenter reported a build warning for CONFIG_CPU_SUP_INTEL=n:

  > With allmodconfig-CONFIG_CPU_SUP_INTEL, this patch results in:
  >
  > In file included from arch/x86/events/amd/core.c:8:0:
  > arch/x86/events/amd/../perf_event.h:1036:45: warning: ‘struct cpu_hw_event’ declared inside parameter list will not be visible outside of this definition or declaration
  >  static inline int intel_cpuc_prepare(struct cpu_hw_event *cpuc, int cpu)

While harmless (an unsed pointer is an unused pointer, no matter the type)
it needs fixing.

Reported-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Fixes: d01b1f96a8 ("perf/x86/intel: Make cpuc allocations consistent")
Link: http://lkml.kernel.org/r/20190315081410.GR5996@hirez.programming.kicks-ass.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-03-15 13:12:42 +01:00
Peter Zijlstra
ede271b059 perf/x86/intel: Fix memory corruption
Through:

  validate_event()
    x86_pmu.get_event_constraints(.idx=-1)
      tfa_get_event_constraints()
        dyn_constraint()

cpuc->constraint_list[-1] is used, which is an obvious out-of-bound access.

In this case, simply skip the TFA constraint code, there is no event
constraint with just PMC3, therefore the code will never result in the
empty set.

Fixes: 400816f60c ("perf/x86/intel: Implement support for TSX Force Abort")
Reported-by: Tony Jones <tonyj@suse.com>
Reported-by: "DSouza, Nelson" <nelson.dsouza@intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Tony Jones <tonyj@suse.com>
Tested-by: "DSouza, Nelson" <nelson.dsouza@intel.com>
Cc: eranian@google.com
Cc: jolsa@redhat.com
Cc: stable@kernel.org
Link: https://lkml.kernel.org/r/20190314130705.441549378@infradead.org
2019-03-15 12:22:51 +01:00
Aurelien Aptel
bc31d0cdcf CIFS: fix POSIX lock leak and invalid ptr deref
We have a customer reporting crashes in lock_get_status() with many
"Leaked POSIX lock" messages preceeding the crash.

 Leaked POSIX lock on dev=0x0:0x56 ...
 Leaked POSIX lock on dev=0x0:0x56 ...
 Leaked POSIX lock on dev=0x0:0x56 ...
 Leaked POSIX lock on dev=0x0:0x53 ...
 Leaked POSIX lock on dev=0x0:0x53 ...
 Leaked POSIX lock on dev=0x0:0x53 ...
 Leaked POSIX lock on dev=0x0:0x53 ...
 POSIX: fl_owner=ffff8900e7b79380 fl_flags=0x1 fl_type=0x1 fl_pid=20709
 Leaked POSIX lock on dev=0x0:0x4b ino...
 Leaked locks on dev=0x0:0x4b ino=0xf911400000029:
 POSIX: fl_owner=ffff89f41c870e00 fl_flags=0x1 fl_type=0x1 fl_pid=19592
 stack segment: 0000 [#1] SMP
 Modules linked in: binfmt_misc msr tcp_diag udp_diag inet_diag unix_diag af_packet_diag netlink_diag rpcsec_gss_krb5 arc4 ecb auth_rpcgss nfsv4 md4 nfs nls_utf8 lockd grace cifs sunrpc ccm dns_resolver fscache af_packet iscsi_ibft iscsi_boot_sysfs vmw_vsock_vmci_transport vsock xfs libcrc32c sb_edac edac_core crct10dif_pclmul crc32_pclmul ghash_clmulni_intel drbg ansi_cprng vmw_balloon aesni_intel aes_x86_64 lrw gf128mul glue_helper ablk_helper cryptd joydev pcspkr vmxnet3 i2c_piix4 vmw_vmci shpchp fjes processor button ac btrfs xor raid6_pq sr_mod cdrom ata_generic sd_mod ata_piix vmwgfx crc32c_intel drm_kms_helper syscopyarea sysfillrect sysimgblt fb_sys_fops ttm serio_raw ahci libahci drm libata vmw_pvscsi sg dm_multipath dm_mod scsi_dh_rdac scsi_dh_emc scsi_dh_alua scsi_mod autofs4

 Supported: Yes
 CPU: 6 PID: 28250 Comm: lsof Not tainted 4.4.156-94.64-default #1
 Hardware name: VMware, Inc. VMware Virtual Platform/440BX Desktop Reference Platform, BIOS 6.00 04/05/2016
 task: ffff88a345f28740 ti: ffff88c74005c000 task.ti: ffff88c74005c000
 RIP: 0010:[<ffffffff8125dcab>]  [<ffffffff8125dcab>] lock_get_status+0x9b/0x3b0
 RSP: 0018:ffff88c74005fd90  EFLAGS: 00010202
 RAX: ffff89bde83e20ae RBX: ffff89e870003d18 RCX: 0000000049534f50
 RDX: ffffffff81a3541f RSI: ffffffff81a3544e RDI: ffff89bde83e20ae
 RBP: 0026252423222120 R08: 0000000020584953 R09: 000000000000ffff
 R10: 0000000000000000 R11: ffff88c74005fc70 R12: ffff89e5ca7b1340
 R13: 00000000000050e5 R14: ffff89e870003d30 R15: ffff89e5ca7b1340
 FS:  00007fafd64be800(0000) GS:ffff89f41fd00000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: 0000000001c80018 CR3: 000000a522048000 CR4: 0000000000360670
 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
 Stack:
  0000000000000208 ffffffff81a3d6b6 ffff89e870003d30 ffff89e870003d18
  ffff89e5ca7b1340 ffff89f41738d7c0 ffff89e870003d30 ffff89e5ca7b1340
  ffffffff8125e08f 0000000000000000 ffff89bc22b67d00 ffff88c74005ff28
 Call Trace:
  [<ffffffff8125e08f>] locks_show+0x2f/0x70
  [<ffffffff81230ad1>] seq_read+0x251/0x3a0
  [<ffffffff81275bbc>] proc_reg_read+0x3c/0x70
  [<ffffffff8120e456>] __vfs_read+0x26/0x140
  [<ffffffff8120e9da>] vfs_read+0x7a/0x120
  [<ffffffff8120faf2>] SyS_read+0x42/0xa0
  [<ffffffff8161cbc3>] entry_SYSCALL_64_fastpath+0x1e/0xb7

When Linux closes a FD (close(), close-on-exec, dup2(), ...) it calls
filp_close() which also removes all posix locks.

The lock struct is initialized like so in filp_close() and passed
down to cifs

	...
        lock.fl_type = F_UNLCK;
        lock.fl_flags = FL_POSIX | FL_CLOSE;
        lock.fl_start = 0;
        lock.fl_end = OFFSET_MAX;
	...

Note the FL_CLOSE flag, which hints the VFS code that this unlocking
is done for closing the fd.

filp_close()
  locks_remove_posix(filp, id);
    vfs_lock_file(filp, F_SETLK, &lock, NULL);
      return filp->f_op->lock(filp, cmd, fl) => cifs_lock()
        rc = cifs_setlk(file, flock, type, wait_flag, posix_lck, lock, unlock, xid);
          rc = server->ops->mand_unlock_range(cfile, flock, xid);
          if (flock->fl_flags & FL_POSIX && !rc)
                  rc = locks_lock_file_wait(file, flock)

Notice how we don't call locks_lock_file_wait() which does the
generic VFS lock/unlock/wait work on the inode if rc != 0.

If we are closing the handle, the SMB server is supposed to remove any
locks associated with it. Similarly, cifs.ko frees and wakes up any
lock and lock waiter when closing the file:

cifs_close()
  cifsFileInfo_put(file->private_data)
	/*
	 * Delete any outstanding lock records. We'll lose them when the file
	 * is closed anyway.
	 */
	down_write(&cifsi->lock_sem);
	list_for_each_entry_safe(li, tmp, &cifs_file->llist->locks, llist) {
		list_del(&li->llist);
		cifs_del_lock_waiters(li);
		kfree(li);
	}
	list_del(&cifs_file->llist->llist);
	kfree(cifs_file->llist);
	up_write(&cifsi->lock_sem);

So we can safely ignore unlocking failures in cifs_lock() if they
happen with the FL_CLOSE flag hint set as both the server and the
client take care of it during the actual closing.

This is not a proper fix for the unlocking failure but it's safe and
it seems to prevent the lock leakages and crashes the customer
experiences.

Signed-off-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: NeilBrown <neil@brown.name>
Signed-off-by: Steve French <stfrench@microsoft.com>
Acked-by: Pavel Shilovsky <pshilov@microsoft.com>
2019-03-14 19:32:36 -05:00
Ronnie Sahlberg
f5778c3987 SMB3: Allow SMB3 FSCTL queries to be sent to server from tools
For debugging purposes we often have to be able to query
additional information only available via SMB3 FSCTL
from the server from user space tools (e.g. like
cifs-utils's smbinfo).  See MS-FSCC and MS-SMB2 protocol
specifications for more details.

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2019-03-14 19:32:36 -05:00
Ronnie Sahlberg
f16994797e cifs: fix incorrect handling of smb2_set_sparse() return in smb3_simple_falloc
smb2_set_sparse does not return -errno, it returns a boolean where
true means success.
Change this to just ignore the return value just like the other callsites.

Additionally add code to handle the case where we must set the file sparse
and possibly also extending it.

Fixes xfstests: generic/236 generic/350 generic/420

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2019-03-14 19:32:36 -05:00
Steve French
dd0ac2d24b smb2: fix typo in definition of a few error flags
As Sergey Senozhatsky pointed out __constant_cpu_to_le32()
is misspelled in a few definitions in the list of status
codes smb2status.h as __constanst_cpu_to_le32()

Signed-off-by: Steve French <stfrench@microsoft.com>
CC: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
2019-03-14 19:32:36 -05:00
Aurelien Aptel
c847dccfbd CIFS: make mknod() an smb_version_op
This cleanup removes cifs specific code from SMB2/SMB3 code paths
which is cleaner and easier to maintain as the code to handle
special files is improved.  Below is an example creating special files
using 'sfu' mount option over SMB3 to Windows (with this patch)
(Note that to Samba server, support for saving dos attributes
has to be enabled for the SFU mount option to work).

In the future this will also make implementation of creating
special files as reparse points easier (as Windows NFS server does
for example).

   root@smf-Thinkpad-P51:~# stat -c "%F" /mnt2/char
   character special file

   root@smf-Thinkpad-P51:~# stat -c "%F" /mnt2/block
   block special file

Signed-off-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
2019-03-14 19:32:36 -05:00
Steve French
6552580286 cifs: minor documentation updates
Also updated a comment describing use of the GlobalMid_Lock

Signed-off-by: Steve French <stfrench@microsoft.com>
2019-03-14 19:32:36 -05:00
Steve French
d44d13723b cifs: remove unused value pointed out by Coverity
Detected by CoverityScan CID#1438719 ("Unused Value")

buf is reset again before being used so these two lines of code
are useless.

Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
2019-03-14 19:32:36 -05:00
Steve French
31ba4331d5 SMB3: passthru query info doesn't check for SMB3 FSCTL passthru
The passthrough queries from user space tools like smbinfo can be either
SMB3 QUERY_INFO or SMB3 FSCTL, but we are not checking for the latter.
Temporarily we return EOPNOTSUPP for SMB3 FSCTL passthrough requests
but once compounding fsctls is fixed can enable.

Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
2019-03-14 19:32:36 -05:00
Steve French
779ede040d smb3: add dynamic tracepoints for simple fallocate and zero range
Can be helpful in debugging various xfstests that are currently
skipped or failing due to missing features in our current
implementation of fallocate.

Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
2019-03-14 19:32:35 -05:00
Ronnie Sahlberg
72c419d9b0 cifs: fix smb3_zero_range so it can expand the file-size when required
This allows fallocate -z to work against a Windows2016 share.

This is due to the SMB3 ZERO_RANGE command does not modify the filesize.
To address this we will now append a compounded SET-INFO to update the
end-of-file information.

This brings xfstests generic/469 closer to working against a windows share.

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2019-03-14 19:32:35 -05:00
Ronnie Sahlberg
ccdc77a305 cifs: add SMB2_ioctl_init/free helpers to be used with compounding
Define an _init() and a _free() function for SMB2_init so that we will
be able to use it with compounds.

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2019-03-14 19:32:35 -05:00
Steve French
8191576a12 smb3: Add dynamic trace points for various compounded smb3 ops
Adds trace points for enter and exit (done vs. error) for:

	compounded query and setinfo, hardlink, rename,
	mkdir, rmdir, set_eof, delete (unlink)

Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
2019-03-14 19:32:35 -05:00
Ronnie Sahlberg
b0f6df737a cifs: cache FILE_ALL_INFO for the shared root handle
When we open the shared root handle also ask for FILE_ALL_INFORMATION since
we can do this at zero cost as part of a compound.
Cache this information as long as the lease is held and return and serve any
future requests from cache.

This allows us to serve "stat /<mountpoint>" directly from cache and avoid
a network roundtrip.  Since clients often want to do this quite a lot
this improve performance slightly.

As an example: xfstest generic/533 performs 43 stat operations on the root
of the share while it is run. Which are eliminated with this patch.

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
2019-03-14 19:32:35 -05:00
Steve French
ab7b10cf4f smb3: display volume serial number for shares in /proc/fs/cifs/DebugData
It can be helpful for debugging.  According to MS-FSCC:

"A 32-bit unsigned integer that contains the serial number of the
volume. The serial number is an opaque value generated by the file
system at format time"

Signed-off-by: Steve French <stfrench@microsoft.com>
Acked-by: Pavel Shilovsky <pshilov@microsoft.com>
2019-03-14 19:32:35 -05:00
Ronnie Sahlberg
257b78099b cifs: simplify how we handle credits in compound_send_recv()
Since we can now wait for multiple requests atomically in
wait_for_free_request() we can now greatly simplify the handling
of the credits in this function.

This fixes a potential deadlock where many concurrent compound requests
could each have reserved 1 or 2 credits each but are all blocked
waiting for the final credits they need to be able to issue the requests
to the server.

Set a default timeout of 60 seconds for compounded requests.

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
2019-03-14 19:32:35 -05:00
Steve French
7937ca961c smb3: add dynamic tracepoint for timeout waiting for credits
To help debug credit starvation problems where we timeout
waiting for server to grant the client credits.

Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
2019-03-14 19:32:35 -05:00
Steve French
ffd1ef1e50 smb3: display security information in /proc/fs/cifs/DebugData more accurately
When the server required encryption (but we didn't connect to it with the
"seal" mount option) we weren't displaying in /proc/fs/cifs/DebugData that
the tcon for that share was encrypted. Similarly we were not displaying
that signing was required when ses->sign was enabled (we only
checked ses->server->sign).  This makes it easier to debug when in
fact the connection is signed (or sealed), whether for performance
or security questions.

Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
2019-03-14 19:32:35 -05:00
Ronnie Sahlberg
2b53b929fa cifs: add a timeout argument to wait_for_free_credits
A negative timeout is the same as the current behaviour, i.e. no timeout.

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
2019-03-14 19:32:35 -05:00
Ronnie Sahlberg
16b34aa44b cifs: prevent starvation in wait_for_free_credits for multi-credit requests
Reserve the last MAX_COMPOUND credits for any request asking for >1 credit.
This is to prevent future compound requests from becoming starved while waiting
for potentially many requests is there is a large number of concurrent
singe-credit requests.

However, we need to protect from servers that are very slow to hand out
new credits on new sessions so we only do this IFF there are 2*MAX_COMPOUND
(arbitrary) credits already in flight.

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
2019-03-14 19:32:35 -05:00
Ronnie Sahlberg
b227d215de cifs: wait_for_free_credits() make it possible to wait for >=1 credits
Change wait_for_free_credits() to allow waiting for >=1 credits instead of just
a single credit.

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
2019-03-14 19:32:35 -05:00
Ronnie Sahlberg
4230cff8c0 cifs: pass flags down into wait_for_free_credits()
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
2019-03-14 19:32:35 -05:00
Ronnie Sahlberg
480b1cb9da cifs: change wait_for_free_request() to take flags as argument
and compute timeout and optyp from it.

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
2019-03-14 19:32:35 -05:00
Masami Hiramatsu
a039480e9e tracing/probe: Verify alloc_trace_*probe() result
Since alloc_trace_*probe() returns -EINVAL only if !event && !group,
it should not happen in trace_*probe_create(). If we catch that case
there is a bug. So use WARN_ON_ONCE() instead of pr_info().

Link: http://lkml.kernel.org/r/155253785078.14922.16902223633734601469.stgit@devnote2

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-03-14 19:54:21 -04:00
Masami Hiramatsu
5b7a962209 tracing/probe: Check event/group naming rule at parsing
Check event and group naming rule at parsing it instead
of allocating probes.

Link: http://lkml.kernel.org/r/155253784064.14922.2336893061156236237.stgit@devnote2

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-03-14 19:54:11 -04:00
Masami Hiramatsu
b4443c17a3 tracing/probe: Check the size of argument name and body
Check the size of argument name and expression is not 0
and smaller than maximum length.

Link: http://lkml.kernel.org/r/155253783029.14922.12650939303827581096.stgit@devnote2

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-03-14 19:53:57 -04:00
Masami Hiramatsu
dec65d79fd tracing/probe: Check event name length correctly
Ensure given name of event is not too long when parsing it,
and fix to update event name offset correctly when the group
name is given. For example, this makes probe event to check
the "p:foo/" error case correctly.

Link: http://lkml.kernel.org/r/155253782046.14922.14724124823730168629.stgit@devnote2

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-03-14 19:53:47 -04:00
Masami Hiramatsu
287c038c0b tracing/probe: Check maxactive error cases
Check maxactive on kprobe error case, because maxactive
is only for kretprobe, not for kprobe. Also, maxactive
should not be 0, it should be at least 1.

Link: http://lkml.kernel.org/r/155253780952.14922.15784129810238750331.stgit@devnote2

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-03-14 19:53:29 -04:00
Linus Torvalds
f261c4e529 Merge branch 'akpm' (patches from Andrew)
Merge misc patches from Andrew Morton:

- a little bit more MM

- a few fixups

[ The "little bit more MM" is actually just one of the three patches
  Andrew sent for mm/filemap.c, I'm still mulling over two more of them
  from Josef Bacik     - Linus ]

* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
  include/linux/swap.h: use offsetof() instead of custom __swapoffset macro
  tools/testing/selftests/proc/proc-pid-vm.c: test with vsyscall in mind
  zram: default to lzo-rle instead of lzo
  filemap: pass vm_fault to the mmap ra helpers
2019-03-14 15:10:10 -07:00
Pi-Hsun Shih
a4046c06be include/linux/swap.h: use offsetof() instead of custom __swapoffset macro
Use offsetof() to calculate offset of a field to take advantage of
compiler built-in version when possible, and avoid UBSAN warning when
compiling with Clang:

  UBSAN: Undefined behaviour in mm/swapfile.c:3010:38
  member access within null pointer of type 'union swap_header'
  CPU: 6 PID: 1833 Comm: swapon Tainted: G S                4.19.23 #43
  Call trace:
   dump_backtrace+0x0/0x194
   show_stack+0x20/0x2c
   __dump_stack+0x20/0x28
   dump_stack+0x70/0x94
   ubsan_epilogue+0x14/0x44
   ubsan_type_mismatch_common+0xf4/0xfc
   __ubsan_handle_type_mismatch_v1+0x34/0x54
   __se_sys_swapon+0x654/0x1084
   __arm64_sys_swapon+0x1c/0x24
   el0_svc_common+0xa8/0x150
   el0_svc_compat_handler+0x2c/0x38
   el0_svc_compat+0x8/0x18

Link: http://lkml.kernel.org/r/20190312081902.223764-1-pihsun@chromium.org
Signed-off-by: Pi-Hsun Shih <pihsun@chromium.org>
Acked-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-03-14 14:36:20 -07:00
Alexey Dobriyan
17415606f9 tools/testing/selftests/proc/proc-pid-vm.c: test with vsyscall in mind
: selftests: proc: proc-pid-vm
: ========================================
: proc-pid-vm: proc-pid-vm.c:277: main: Assertion `rv == strlen(buf0)' failed.
: Aborted

Because the vsyscall mapping is enabled.  Read from vsyscall page to tell
if vsyscall is being used.

Link: http://lkml.kernel.org/r/20190307183204.GA11405@avx2
Link: http://lkml.kernel.org/r/20190219094722.GB28258@shao2-debian
Fixes: 34aab6bec23e7e9 ("proc: test /proc/*/maps, smaps, smaps_rollup, statm")
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Reported-by: kernel test robot <rong.a.chen@intel.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>
2019-03-14 14:36:20 -07:00
Dave Rodgman
ce82f19fd5 zram: default to lzo-rle instead of lzo
lzo-rle gives higher performance and similar compression ratios to lzo.

Link: http://lkml.kernel.org/r/20190205155944.16007-4-dave.rodgman@arm.com
Signed-off-by: Dave Rodgman <dave.rodgman@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-03-14 14:36:20 -07:00
Josef Bacik
2a1180f1bd filemap: pass vm_fault to the mmap ra helpers
All of the arguments to these functions come from the vmf.

Cut down on the amount of arguments passed by simply passing in the vmf
to these two helpers.

Link: http://lkml.kernel.org/r/20181211173801.29535-3-josef@toxicpanda.com
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: "Kirill A. Shutemov" <kirill@shutemov.name>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-03-14 14:36:20 -07:00
Linus Torvalds
3b319ee220 Additional ACPI updates for 5.1-rc1
- Fix a crash caused by unloading an SSDT overlay (Andy Shevchenko).
 
  - Prevent user space from getting confusing error values on failing
    ACPI sysfs accesses (Rafael Wysocki).
 
  - Simplify leaf node detection in the PPTT parsing code by using a
    new flag defined in ACPI 6.3 (Jeremy Linton).
 
  - Add missing "static" in some places in the ACPI configfs code
    (Andy Shevchenko).
 
  - Fix acpidbg tool path in the ACPI documentation (Flavio Suligoi).
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Merge tag 'acpi-5.1-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull more ACPI updates from Rafael Wysocki:
 "These fix a couple of issues and do some cleanups on top of the
  previous ACPI changes for 5.1-rc1.

  Specifics:

   - Fix a crash caused by unloading an SSDT overlay (Andy Shevchenko)

   - Prevent user space from getting confusing error values on failing
     ACPI sysfs accesses (Rafael Wysocki)

   - Simplify leaf node detection in the PPTT parsing code by using a
     new flag defined in ACPI 6.3 (Jeremy Linton)

   - Add missing "static" in some places in the ACPI configfs code (Andy
     Shevchenko)

   - Fix acpidbg tool path in the ACPI documentation (Flavio Suligoi)"

* tag 'acpi-5.1-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  ACPI: sysfs: Prevent get_status() from returning acpi_status
  ACPI / device_sysfs: Avoid OF modalias creation for removed device
  ACPI / configfs: Mark local data structures static
  ACPI / configfs: Mark local functions static
  ACPI: tables: Simplify PPTT leaf node detection
  ACPI: Documentation: Fix path for acpidbg tool
2019-03-14 10:48:14 -07:00
Linus Torvalds
9352ca585b Additional power management updates for 5.1-rc1
- Fix registration of new cpuidle governors partially broken during
    the 5.0 development cycle by mistake (Rafael Wysocki).
 
  - Avoid integer overflows in the menu cpuidle governor by making
    it discard the overflowing data points upfront (Rafael Wysocki).
 
  - Fix minor mistake in the recent update of the iowait boost
    computation in the intel_pstate driver (Rafael Wysocki).
 
  - Drop incorrect __init annotation from one function in the pxa2xx
    cpufreq driver (Arnd Bergmann).
 
  - Fix the operating performance points (OPP) framework
    initialization for devices in multiple power domains if
    only one of them is scalable (Rajendra Nayak).
 
  - Fix mistake in dev_pm_opp_set_rate() which causes it to skip
    updating the performance state if the new frequency is the same
    as the old one (Viresh Kumar).
 
  - Rework the cancellation of wakeup source timers to avoid
    potential issues with it and do some cleanups unlocked by
    that change (Viresh Kumar, Rafael Wysocki).
 
  - Clean up the code computing the active/suspended time of devices
    in the PM-runtime framework after recent changes (Ulf Hansson).
 
  - Make the power management infrastructure code use pr_fmt()
    consistently (Joe Perches).
 
  - Clean up the generic power domains (genpd) framework somewhat
    (Aisheng Dong).
 
  - Improve kerneldoc comments for two functions in the cpufreq core
    (Rafael Wysocki).
 
  - Fix typo in a PM QoS file description comment (Aisheng Dong).
 
  - Update the handling of CPU boost frequencies in the cpupower
    utility (Abhishek Goel).
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Merge tag 'pm-5.1-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull more power management updates from Rafael Wysocki:
 "These are mostly fixes and cleanups on top of the previously merged
  power management material for 5.1-rc1 with one cpupower utility update
  that wasn't pushed earlier due to unfortunate timing.

  Specifics:

   - Fix registration of new cpuidle governors partially broken during
     the 5.0 development cycle by mistake (Rafael Wysocki).

   - Avoid integer overflows in the menu cpuidle governor by making it
     discard the overflowing data points upfront (Rafael Wysocki).

   - Fix minor mistake in the recent update of the iowait boost
     computation in the intel_pstate driver (Rafael Wysocki).

   - Drop incorrect __init annotation from one function in the pxa2xx
     cpufreq driver (Arnd Bergmann).

   - Fix the operating performance points (OPP) framework initialization
     for devices in multiple power domains if only one of them is
     scalable (Rajendra Nayak).

   - Fix mistake in dev_pm_opp_set_rate() which causes it to skip
     updating the performance state if the new frequency is the same as
     the old one (Viresh Kumar).

   - Rework the cancellation of wakeup source timers to avoid potential
     issues with it and do some cleanups unlocked by that change (Viresh
     Kumar, Rafael Wysocki).

   - Clean up the code computing the active/suspended time of devices in
     the PM-runtime framework after recent changes (Ulf Hansson).

   - Make the power management infrastructure code use pr_fmt()
     consistently (Joe Perches).

   - Clean up the generic power domains (genpd) framework somewhat
     (Aisheng Dong).

   - Improve kerneldoc comments for two functions in the cpufreq core
     (Rafael Wysocki).

   - Fix typo in a PM QoS file description comment (Aisheng Dong).

   - Update the handling of CPU boost frequencies in the cpupower
     utility (Abhishek Goel)"

* tag 'pm-5.1-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  cpuidle: governor: Add new governors to cpuidle_governors again
  cpufreq: intel_pstate: Fix up iowait_boost computation
  PM / OPP: Update performance state when freq == old_freq
  PM / wakeup: Drop wakeup_source_drop()
  PM / wakeup: Rework wakeup source timer cancellation
  PM / domains: Remove one unnecessary blank line
  PM / Domains: Return early for all errors in _genpd_power_off()
  PM / Domains: Improve warn for multiple states but no governor
  OPP: Fix handling of multiple power domains
  PM / QoS: Fix typo in file description
  cpufreq: pxa2xx: remove incorrect __init annotation
  PM-runtime: Call pm_runtime_active|suspended_time() from sysfs
  PM-runtime: Consolidate code to get active/suspended time
  PM: Add and use pr_fmt()
  cpufreq: Improve kerneldoc comments for cpufreq_cpu_get/put()
  cpuidle: menu: Avoid overflows when computing variance
  tools/power/cpupower: Display boost frequency separately
2019-03-14 10:30:06 -07:00