It is very useful to be able to know whether or not get_random_bytes_wait
/ wait_for_random_bytes is going to block or not, or whether plain
get_random_bytes is going to return good randomness or bad randomness.
The particular use case is for mitigating certain attacks in WireGuard.
A handshake packet arrives and is queued up. Elsewhere a worker thread
takes items from the queue and processes them. In replying to these
items, it needs to use some random data, and it has to be good random
data. If we simply block until we can have good randomness, then it's
possible for an attacker to fill the queue up with packets waiting to be
processed. Upon realizing the queue is full, WireGuard will detect that
it's under a denial of service attack, and behave accordingly. A better
approach is just to drop incoming handshake packets if the crng is not
yet initialized.
This patch, therefore, makes that information directly accessible.
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
There is a lot of needless struct request_sense usage in the CDROM
code. These can all be struct scsi_sense_hdr instead, to avoid any
confusion over their respective structure sizes. This patch is a lot
of noise changing "sense" to "sshdr", but the final code is more
readable to distinguish between "sense" meaning "struct request_sense"
and "sshdr" meaning "struct scsi_sense_hdr".
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Introduce these two functions and export them such that the next patch
can add calls to these functions from the SCSI core.
Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com>
Acked-by: Tejun Heo <tj@kernel.org>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Derive the signature from the entire buffer (both AES cipher blocks)
instead of using just the first half of the first block, leaving out
data_crc entirely.
This addresses CVE-2018-1129.
Link: http://tracker.ceph.com/issues/24837
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Reviewed-by: Sage Weil <sage@redhat.com>
When a client authenticates with a service, an authorizer is sent with
a nonce to the service (ceph_x_authorize_[ab]) and the service responds
with a mutation of that nonce (ceph_x_authorize_reply). This lets the
client verify the service is who it says it is but it doesn't protect
against a replay: someone can trivially capture the exchange and reuse
the same authorizer to authenticate themselves.
Allow the service to reject an initial authorizer with a random
challenge (ceph_x_authorize_challenge). The client then has to respond
with an updated authorizer proving they are able to decrypt the
service's challenge and that the new authorizer was produced for this
specific connection instance.
The accepting side requires this challenge and response unconditionally
if the client side advertises they have CEPHX_V2 feature bit.
This addresses CVE-2018-1128.
Link: http://tracker.ceph.com/issues/24836
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Reviewed-by: Sage Weil <sage@redhat.com>
We already copy authorizer_reply_buf and authorizer_reply_buf_len into
ceph_connection. Factoring out __prepare_write_connect() requires two
more: authorizer_buf and authorizer_buf_len. Store the pointer to the
handshake in con->auth rather than piling on.
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Reviewed-by: Sage Weil <sage@redhat.com>
The request mtime field is used all over ceph, and is currently
represented as a 'timespec' structure in Linux. This changes it to
timespec64 to allow times beyond 2038, modifying all users at the
same time.
[ Remove now redundant ts variable in writepage_nounlock(). ]
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
ceph_con_keepalive_expired() is the last user of timespec_add() and some
of the last uses of ktime_get_real_ts(). Replacing this with timespec64
based interfaces lets us remove that deprecated API.
I'm introducing new ceph_encode_timespec64()/ceph_decode_timespec64()
here that take timespec64 structures and convert to/from ceph_timespec,
which is defined to have an unsigned 32-bit tv_sec member. This extends
the range of valid times to year 2106, avoiding the year 2038 overflow.
The ceph file system portion still uses the old functions for inode
timestamps, this will be done separately after the VFS layer is converted.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
The wire format dictates that the length of string fits into 4 bytes.
Take u32 instead of size_t to reflect that.
We were already truncating len in ceph_pagelist_encode_32() -- this
just pushes that truncation one level up.
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
The wire format dictates that payload_len fits into 4 bytes. Take u32
instead of size_t to reflect that.
All callers pass a small integer, so no changes required.
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
This contains a set of early-boot memory-management docs from Mike
Rapoport. It's been circulating on linux-mm for a long time; I finally
picked it up even though it changes a lot of .c files under mm/ (comments
only).
* make memblock_discard description kernel-doc compatible
* add brief description for memblock_setclr_flag and describe its
parameters
* fixup return value descriptions
Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Since kernel-doc does not like anonymous enums the name is required for
adding documentation. While on it, I've also updated all the function
declarations to use 'enum memblock_flags' instead of unsigned long.
Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
The BTF conflicts were simple overlapping changes.
The virtio_net conflict was an overlap of a fix of statistics counter,
happening alongisde a move over to a bonafide statistics structure
rather than counting value on the stack.
Signed-off-by: David S. Miller <davem@davemloft.net>
When porting (Q)SPI controller drivers from the MTD layer to the SPI
layer, the naming scheme for the memory devices changes. To be able
to keep compatibility with the old drivers naming scheme, a name
field is added to struct spi_mem and a hook is added to let controller
drivers set a custom name for the memory device.
Example for the FSL QSPI driver:
Name with the old driver: 21e0000.qspi,
or with multiple devices: 21e0000.qspi-0, 21e0000.qspi-1, ...
Name with the new driver without spi_mem_get_name: spi4.0
Suggested-by: Boris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: Frieder Schrempf <frieder.schrempf@exceet.de>
Reviewed-by: Boris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Fix a typo in the @drvpriv description.
Signed-off-by: Frieder Schrempf <frieder.schrempf@exceet.de>
Acked-by: Boris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
There are dedicated macros (lower_32_bits and upper_32_bits)
available to extract the lower and upper 32 bits. They provide
better readability and could prevent some compilation warnings.
Signed-off-by: Roman Kiryanov <rkir@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
goldfish.h refers to external symbols such as
dma_addr_t and writel. This causes compilation errors
if this file is included before other header files.
The mentioned symbols are defined in types.h (dma_addr_t)
and io.h (writel).
Signed-off-by: Roman Kiryanov <rkir@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Before setting channel->rescind in vmbus_rescind_cleanup(), we should make
sure the channel callback won't run any more, otherwise a high-level
driver like pci_hyperv, which may be infinitely waiting for the host VSP's
response and notices the channel has been rescinded, can't safely give
up: e.g., in hv_pci_protocol_negotiation() -> wait_for_response(), it's
unsafe to exit from wait_for_response() and proceed with the on-stack
variable "comp_pkt" popped. The issue was originally spotted by
Michael Kelley <mikelley@microsoft.com>.
In vmbus_close_internal(), the patch also minimizes the range protected by
disabling/enabling channel->callback_event: we don't really need that for
the whole function.
Signed-off-by: Dexuan Cui <decui@microsoft.com>
Reviewed-by: Michael Kelley <mikelley@microsoft.com>
Cc: stable@vger.kernel.org
Cc: K. Y. Srinivasan <kys@microsoft.com>
Cc: Stephen Hemminger <sthemmin@microsoft.com>
Cc: Michael Kelley <mikelley@microsoft.com>
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
There is no more need for SCIx_RZ_SCIFA_REGTYPE now that
SCIx_SH4_SCIF_REGTYPE can provide the same register/address definitions.
Also, R7S9210 no longer needs a special compatible since the standard
"renesas,scif" will work just fine.
Signed-off-by: Chris Brandt <chris.brandt@renesas.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The only user is fuse_create_new_entry(), and there it's used to
mitigate the same mkdir/open-by-handle race as in nfs_mkdir().
The same solution applies - unhash the mkdir argument, then
call d_splice_alias() and if that returns a reference to preexisting
alias, dput() and report success. ->mkdir() argument left unhashed
negative with the preexisting alias moved in the right place is just
fine from the ->mkdir() callers point of view.
Cc: Miklos Szeredi <miklos@szeredi.hu>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
The value of ring_buffer_record_is_set_on() is either true or false, so have
its return value be bool.
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
The value of ring_buffer_record_is_on() is either true or false, so have its
return value be bool.
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
A lot of code become ugly because of open coding allocations for bitmaps.
Introduce three helpers to allow users be more clear of intention
and keep their code neat.
Note, due to multiple circular dependencies we may not provide
the helpers as inliners. For now we keep them exported and, perhaps,
at some point in the future we will sort out header inclusion and
inheritance.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Commit 2c4541e24c ("mm: use vma_init() to initialize VMAs on stack and
data segments") tried to initialize various left-over ad-hoc vma's
"properly", but actually made things worse for the temporary vma's used
for TLB flushing.
vma_init() doesn't actually initialize all of the vma, just a few
fields, so doing something like
- struct vm_area_struct vma = { .vm_mm = tlb->mm, };
+ struct vm_area_struct vma;
+
+ vma_init(&vma, tlb->mm);
was actually very bad: instead of having a nicely initialized vma with
every field but "vm_mm" zeroed, you'd have an entirely uninitialized vma
with only a couple of fields initialized. And they weren't even fields
that the code in question mostly cared about.
The flush_tlb_range() function takes a "struct vma" rather than a
"struct mm_struct", because a few architectures actually care about what
kind of range it is - being able to only do an ITLB flush if it's a
range that doesn't have data accesses enabled, for example. And all the
normal users already have the vma for doing the range invalidation.
But a few people want to call flush_tlb_range() with a range they just
made up, so they also end up using a made-up vma. x86 just has a
special "flush_tlb_mm_range()" function for this, but other
architectures (arm and ia64) do the "use fake vma" thing instead, and
thus got caught up in the vma_init() changes.
At the same time, the TLB flushing code really doesn't care about most
other fields in the vma, so vma_init() is just unnecessary and
pointless.
This fixes things by having an explicit "this is just an initializer for
the TLB flush" initializer macro, which is used by the arm/arm64/ia64
people who mis-use this interface with just a dummy vma.
Fixes: 2c4541e24c ("mm: use vma_init() to initialize VMAs on stack and data segments")
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Kirill Shutemov <kirill.shutemov@linux.intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Hugh Dickins <hughd@google.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Introduce a new TCP stats to record the number of reordering events seen
and expose it in both tcp_info (TCP_INFO) and opt_stats
(SOF_TIMESTAMPING_OPT_STATS).
Application can use this stats to track the frequency of the reordering
events in addition to the existing reordering stats which tracks the
magnitude of the latest reordering event.
Note: this new stats tracks reordering events triggered by ACKs, which
could often be fewer than the actual number of packets being delivered
out-of-order.
Signed-off-by: Wei Wang <weiwan@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Neal Cardwell <ncardwell@google.com>
Acked-by: Soheil Hassas Yeganeh <soheil@google.com>
Acked-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Introduce a new TCP stat to record the number of DSACK blocks received
(RFC4989 tcpEStatsStackDSACKDups) and expose it in both tcp_info
(TCP_INFO) and opt_stats (SOF_TIMESTAMPING_OPT_STATS).
Signed-off-by: Wei Wang <weiwan@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Neal Cardwell <ncardwell@google.com>
Acked-by: Soheil Hassas Yeganeh <soheil@google.com>
Acked-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Introduce a new TCP stat to record the number of bytes retransmitted
(RFC4898 tcpEStatsPerfOctetsRetrans) and expose it in both tcp_info
(TCP_INFO) and opt_stats (SOF_TIMESTAMPING_OPT_STATS).
Signed-off-by: Wei Wang <weiwan@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Neal Cardwell <ncardwell@google.com>
Acked-by: Soheil Hassas Yeganeh <soheil@google.com>
Acked-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Introduce a new TCP stat to record the number of bytes sent
(RFC4898 tcpEStatsPerfHCDataOctetsOut) and expose it in both tcp_info
(TCP_INFO) and opt_stats (SOF_TIMESTAMPING_OPT_STATS).
Signed-off-by: Wei Wang <weiwan@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Neal Cardwell <ncardwell@google.com>
Acked-by: Soheil Hassas Yeganeh <soheil@google.com>
Acked-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add SPI_3WIRE support to spi-gpio controller introducing
set_line_direction function pointer in spi_bitbang data structure.
Spi-gpio controller has been tested using hts221 temp/rh iio sensor
running in 3wire mode and lsm6dsm running in 4wire mode
Signed-off-by: Lorenzo Bianconi <lorenzo.bianconi@redhat.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Add the capability to specify the flag parameter used in
bitbang_txrx_be_cpha{0,1} through the txrx_word function pointers of
spi_bitbang data structure. That feature will be used to add spi-3wire
support to the spi-gpio controller
Signed-off-by: Lorenzo Bianconi <lorenzo.bianconi@redhat.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Now that it is possible to do dynamic allocations during the
identification phase, convert the onfi_params structure (which is only
needed with ONFI compliant chips) into a pointer that will be allocated
only if needed.
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Reviewed-by: Boris Brezillon <boris.brezillon@bootlin.com>
Commit 59b356ffd0 ("mtd: m25p80: restore the status of SPI flash when
exiting") is the latest from a long history of attempts to add reboot
handling to handle stateful addressing modes on SPI flash. Some prior
mostly-related discussions:
http://lists.infradead.org/pipermail/linux-mtd/2013-March/046343.html
[PATCH 1/3] mtd: m25p80: utilize dedicated 4-byte addressing commands
http://lists.infradead.org/pipermail/barebox/2014-September/020682.html
[RFC] MTD m25p80 3-byte addressing and boot problem
http://lists.infradead.org/pipermail/linux-mtd/2015-February/057683.html
[PATCH 2/2] m25p80: if supported put chip to deep power down if not used
Previously, attempts to add reboot-time software reset handling were
rejected, but the latest attempt was not.
Quick summary of the problem:
Some systems (e.g., boot ROM or bootloader) assume that they can read
initial boot code from their SPI flash using 3-byte addressing. If the
flash is left in 4-byte mode after reset, these systems won't boot. The
above patch provided a shutdown/remove hook to attempt to reset the
addressing mode before we reboot. Notably, this patch misses out on
huge classes of unexpected reboots (e.g., crashes, watchdog resets).
Unfortunately, it is essentially impossible to solve this problem 100%:
if your system doesn't know how to reset the SPI flash to power-on
defaults at initialization time, no amount of software can really rescue
you -- there will always be a chance of some unexpected reset that
leaves your flash in an addressing mode that your boot sequence didn't
expect.
While it is not directly harmful to perform hacks like the
aforementioned commit on all 4-byte addressing flash, a
properly-designed system should not need the hack -- and in fact,
providing this hack may mask the fact that a given system is indeed
broken. So this patch attempts to apply this unsound hack more narrowly,
providing a strong suggestion to developers and system designers that
this is truly a hack. With luck, system designers can catch their errors
early on in their development cycle, rather than applying this hack long
term. But apparently enough systems are out in the wild that we still
have to provide this hack.
Document a new device tree property to denote systems that do not have a
proper hardware (or software) reset mechanism, and apply the hack (with
a loud warning) only in this case.
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>
Current DMA direction definitions in pci-dma-compat.h and dma-direction.h
are mirrored in value. Unify them to enhance readability and avoid
possible inconsistency.
Signed-off-by: Shunyong Yang <shunyong.yang@hxt-semitech.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Cc: Joey Zheng <yu.zheng@hxt-semitech.com>
A bit larger this time around, due to introduction of "dpu1" support
for the display controller in sdm845 and beyond. This has been on
list and undergoing refactoring since Feb (going from ~110kloc to
~30kloc), and all my review complaints have been addressed, so I'd be
happy to see this upstream so further feature work can procede on top
of upstream.
Also includes the gpu coredump support, which should be useful for
debugging gpu crashes. And various other misc fixes and such.
Signed-off-by: Dave Airlie <airlied@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/CAF6AEGv-8y3zguY0Mj1vh=o+vrv_bJ8AwZ96wBXYPvMeQT2XcA@mail.gmail.com
dm_kcopyd_copy() only ever returns 0 so there is no need for callers to
account for possible failure. Same goes for dm_kcopyd_zero().
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
We never use RCU protection for it, just a lot of cargo-cult
rcu_deference_protects calls.
Note that we do keep the kfree_rcu call for it, as the references through
struct sock are RCU protected and thus might require a grace period before
freeing.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
After a live data migration event at the NFS server, the client may send
I/O requests to the wrong server, causing a live hang due to repeated
recovery events. On the wire, this will appear as an I/O request failing
with NFS4ERR_BADSESSION, followed by successful CREATE_SESSION, repeatedly.
NFS4ERR_BADSSESSION is returned because the session ID being used was
issued by the other server and is not valid at the old server.
The failure is caused by async worker threads having cached the transport
(xprt) in the rpc_task structure. After the migration recovery completes,
the task is redispatched and the task resends the request to the wrong
server based on the old value still present in tk_xprt.
The solution is to recompute the tk_xprt field of the rpc_task structure
so that the request goes to the correct server.
Signed-off-by: Bill Baker <bill.baker@oracle.com>
Reviewed-by: Chuck Lever <chuck.lever@oracle.com>
Tested-by: Helen Chao <helen.chao@oracle.com>
Fixes: fb43d17210 ("SUNRPC: Use the multipath iterator to assign a ...")
Cc: stable@vger.kernel.org # v4.9+
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
The existing rpc_print_iostats has a few shortcomings. First, the naming
is not consistent with other functions in the kernel that display stats.
Second, it is really displaying stats for an rpc_clnt structure as it
displays both xprt stats and per-op stats. Third, it does not handle
rpc_clnt clones, which is important for the one in-kernel tree caller
of this function, the NFS client's nfs_show_stats function.
Fix all of the above by renaming the rpc_print_iostats to
rpc_clnt_show_stats and looping through any rpc_clnt clones via
cl_parent.
Once this interface is fixed, this addresses a problem with NFSv4.
Before this patch, the /proc/self/mountstats always showed incorrect
counts for NFSv4 lease and session related opcodes such as SEQUENCE,
RENEW, SETCLIENTID, CREATE_SESSION, etc. These counts were always 0
even though many ops would go over the wire. The reason for this is
there are multiple rpc_clnt structures allocated for any given NFSv4
mount, and inside nfs_show_stats() we callled into rpc_print_iostats()
which only handled one of them, nfs_server->client. Fix these counts
by calling sunrpc's new rpc_clnt_show_stats() function, which handles
cloned rpc_clnt structs and prints the stats together.
Note that one side-effect of the above is that multiple mounts from
the same NFS server will show identical counts in the above ops due
to the fact the one rpc_clnt (representing the NFSv4 client state)
is shared across mounts.
Signed-off-by: Dave Wysochanski <dwysocha@redhat.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Currently drivers have to check if they already have a umem
installed for a given queue and return an error if so. Make
better use of XDP_QUERY_XSK_UMEM and move this functionality
to the core.
We need to keep rtnl across the calls now.
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com>
Acked-by: Björn Töpel <bjorn.topel@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
We used to depend on real_num_rx_queues as a upper bound for sanity
checks. For AF_XDP socket validation it's useful if the check behaves
the same regardless of CONFIG_SYSFS setting.
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When a PCI device is detected, pdev->is_added is set to 1 and proc and
sysfs entries are created.
When the device is removed, pdev->is_added is checked for one and then
device is detached with clearing of proc and sys entries and at end,
pdev->is_added is set to 0.
is_added and is_busmaster are bit fields in pci_dev structure sharing same
memory location.
A strange issue was observed with multiple removal and rescan of a PCIe
NVMe device using sysfs commands where is_added flag was observed as zero
instead of one while removing device and proc,sys entries are not cleared.
This causes issue in later device addition with warning message
"proc_dir_entry" already registered.
Debugging revealed a race condition between the PCI core setting the
is_added bit in pci_bus_add_device() and the NVMe driver reset work-queue
setting the is_busmaster bit in pci_set_master(). As these fields are not
handled atomically, that clears the is_added bit.
Move the is_added bit to a separate private flag variable and use atomic
functions to set and retrieve the device addition state. This avoids the
race because is_added no longer shares a memory location with is_busmaster.
Link: https://bugzilla.kernel.org/show_bug.cgi?id=200283
Signed-off-by: Hari Vyas <hari.vyas@broadcom.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Lukas Wunner <lukas@wunner.de>
Acked-by: Michael Ellerman <mpe@ellerman.id.au>
