Bartosz Golaszewski <bgolaszewski@baylibre.com>:
From: Bartosz Golaszewski <bgolaszewski@baylibre.com>
I noticed that oftentimes I use regmap_update_bits() for simple bit
setting or clearing. In this case the fourth argument is superfluous as
it's always 0 or equal to the mask argument.
This series proposes to add simple bit operations for setting, clearing
and testing specific bits with regmap.
The second patch uses all three in a driver that got recently picked into
the net-next tree.
The patches obviously target different trees so - if you're ok with
the change itself - I propose you pick the first one into your regmap
tree for v5.8 and then I'll resend the second patch to add the first
user for these macros for v5.9.
v1 -> v2:
- convert the new macros to static inline functions
v2 -> v3:
- drop unneeded ternary operator
Bartosz Golaszewski (2):
regmap: provide helpers for simple bit operations
net: ethernet: mtk-star-emac: use regmap bitops
drivers/base/regmap/regmap.c | 22 +++++
drivers/net/ethernet/mediatek/mtk_star_emac.c | 80 ++++++++-----------
include/linux/regmap.h | 36 +++++++++
3 files changed, 93 insertions(+), 45 deletions(-)
base-commit: 8f3d9f3542
--
2.26.1
_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.orghttp://lists.infradead.org/mailman/listinfo/linux-arm-kernel
Looking at the Felix and Ocelot drivers, Maxim asked if it would be
possible to use them as a base for a new driver for the switch inside
NXP T1040. Turns out, it is! The result is a driver eerily similar to
Felix.
The biggest challenge seems to be getting register read/write API
generic enough to cover such wild bitfield variations between hardware
generations. There is a patch on the regmap core which I would like to
get in through the networking subsystem, if possible (and if Mark is
ok), since it's a trivial addition.
Maxim Kochetkov (4):
soc/mscc: ocelot: add MII registers description
net: mscc: ocelot: convert SYS_PAUSE_CFG register access to regfield
net: mscc: ocelot: extend watermark encoding function
net: dsa: ocelot: introduce driver for Seville VSC9953 switch
Vladimir Oltean (7):
regmap: add helper for per-port regfield initialization
net: mscc: ocelot: unexport ocelot_probe_port
net: mscc: ocelot: convert port registers to regmap
net: mscc: ocelot: convert QSYS_SWITCH_PORT_MODE and SYS_PORT_MODE to
regfields
net: dsa: ocelot: create a template for the DSA tags on xmit
net: mscc: ocelot: split writes to pause frame enable bit and to
thresholds
net: mscc: ocelot: disable flow control on NPI interface
drivers/net/dsa/ocelot/Kconfig | 12 +
drivers/net/dsa/ocelot/Makefile | 6 +
drivers/net/dsa/ocelot/felix.c | 49 +-
drivers/net/dsa/ocelot/felix_vsc9959.c | 72 +-
drivers/net/dsa/ocelot/seville.c | 742 +++++++++++++++
drivers/net/dsa/ocelot/seville.h | 50 +
drivers/net/dsa/ocelot/seville_vsc9953.c | 1064 ++++++++++++++++++++++
drivers/net/ethernet/mscc/ocelot.c | 87 +-
drivers/net/ethernet/mscc/ocelot.h | 9 +-
drivers/net/ethernet/mscc/ocelot_board.c | 21 +-
drivers/net/ethernet/mscc/ocelot_io.c | 18 +-
drivers/net/ethernet/mscc/ocelot_regs.c | 57 ++
include/linux/regmap.h | 8 +
include/soc/mscc/ocelot.h | 68 +-
include/soc/mscc/ocelot_dev.h | 78 --
include/soc/mscc/ocelot_qsys.h | 13 -
include/soc/mscc/ocelot_sys.h | 23 -
net/dsa/tag_ocelot.c | 21 +-
18 files changed, 2196 insertions(+), 202 deletions(-)
create mode 100644 drivers/net/dsa/ocelot/seville.c
create mode 100644 drivers/net/dsa/ocelot/seville.h
create mode 100644 drivers/net/dsa/ocelot/seville_vsc9953.c
base-commit: 8f3d9f3542
--
2.25.1
In many instances regmap_update_bits() is used for simple bit setting
and clearing. In these cases the last argument is redundant and we can
hide it with a static inline function.
This adds three new helpers for simple bit operations: set_bits,
clear_bits and test_bits (the last one defined as a regular function).
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Link: https://lore.kernel.org/r/20200528154503.26304-2-brgl@bgdev.pl
Signed-off-by: Mark Brown <broonie@kernel.org>
Similar to the standalone regfields, add an initializer for the users
who need to set .id_size and .id_offset in order to use the
regmap_fields_update_bits_base API.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Link: https://lore.kernel.org/r/20200527234113.2491988-2-olteanv@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>
We provided the right semantics on open drain lines being
by definition output but incidentally the irq set up function
would only allow IRQs on lines that were "not output".
Fix the semantics to allow output open drain lines to be used
for IRQs.
Reported-by: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>
Tested-by: Hans Verkuil <hverkuil@xs4all.nl>
Cc: Russell King <linux@armlinux.org.uk>
Cc: stable@vger.kernel.org # v5.3+
Link: https://lore.kernel.org/r/20200527140758.162280-1-linus.walleij@linaro.org
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
This patch is to fix a crash:
[ ] kasan: GPF could be caused by NULL-ptr deref or user memory access
[ ] general protection fault: 0000 [#1] SMP KASAN PTI
[ ] RIP: 0010:ipv6_local_error+0xac/0x7a0
[ ] Call Trace:
[ ] xfrm6_local_error+0x1eb/0x300
[ ] xfrm_local_error+0x95/0x130
[ ] __xfrm6_output+0x65f/0xb50
[ ] xfrm6_output+0x106/0x46f
[ ] udp_tunnel6_xmit_skb+0x618/0xbf0 [ip6_udp_tunnel]
[ ] vxlan_xmit_one+0xbc6/0x2c60 [vxlan]
[ ] vxlan_xmit+0x6a0/0x4276 [vxlan]
[ ] dev_hard_start_xmit+0x165/0x820
[ ] __dev_queue_xmit+0x1ff0/0x2b90
[ ] ip_finish_output2+0xd3e/0x1480
[ ] ip_do_fragment+0x182d/0x2210
[ ] ip_output+0x1d0/0x510
[ ] ip_send_skb+0x37/0xa0
[ ] raw_sendmsg+0x1b4c/0x2b80
[ ] sock_sendmsg+0xc0/0x110
This occurred when sending a v4 skb over vxlan6 over ipsec, in which case
skb->protocol == htons(ETH_P_IPV6) while skb->sk->sk_family == AF_INET in
xfrm_local_error(). Then it will go to xfrm6_local_error() where it tries
to get ipv6 info from a ipv4 sk.
This issue was actually fixed by Commit 628e341f31 ("xfrm: make local
error reporting more robust"), but brought back by Commit 844d48746e
("xfrm: choose protocol family by skb protocol").
So to fix it, we should call xfrm6_local_error() only when skb->protocol
is htons(ETH_P_IPV6) and skb->sk->sk_family is AF_INET6.
Fixes: 844d48746e ("xfrm: choose protocol family by skb protocol")
Reported-by: Xiumei Mu <xmu@redhat.com>
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
comparison
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Merge tag 'drm-misc-fixes-2020-05-28' of git://anongit.freedesktop.org/drm/drm-misc into drm-fixes
Two ingenic fixes, one for a wrong cast, the other for a typo in a
comparison
Signed-off-by: Dave Airlie <airlied@redhat.com>
From: Maxime Ripard <maxime@cerno.tech>
Link: https://patchwork.freedesktop.org/patch/msgid/20200528110944.hanv4qgc6w7whnj3@gilmour.lan
Recent change in virtio_net_hdr_to_skb() broke some packetdrill tests.
When --mss=XXX option is set, packetdrill always provide gso_type & gso_size
for its inbound packets, regardless of packet size.
if (packet->tcp && packet->mss) {
if (packet->ipv4)
gso.gso_type = VIRTIO_NET_HDR_GSO_TCPV4;
else
gso.gso_type = VIRTIO_NET_HDR_GSO_TCPV6;
gso.gso_size = packet->mss;
}
Since many other programs could do the same, relax virtio_net_hdr_to_skb()
to no longer return an error, but instead ignore gso settings.
This keeps Willem intent to make sure no malicious packet could
reach gso stack.
Note that TCP stack has a special logic in tcp_set_skb_tso_segs()
to clear gso_size for small packets.
Fixes: 6dd912f826 ("net: check untrusted gso_size at kernel entry")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Willem de Bruijn <willemb@google.com>
Acked-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Make sure SCTP_ADDR_{MADE_PRIM,ADDED} are sent only for associations
that have been established.
These events are described in rfc6458#section-6.1
SCTP_PEER_ADDR_CHANGE:
This tag indicates that an address that is
part of an existing association has experienced a change of
state (e.g., a failure or return to service of the reachability
of an endpoint via a specific transport address).
Signed-off-by: Jonas Falkevik <jonas.falkevik@gmail.com>
Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Reviewed-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
In the copy_process() routine called by _do_fork(), failure to allocate
a PID (or further along in the function) will trigger an invocation to
exit_thread(). This is done to clean up from an earlier call to
copy_thread_tls(). Naturally, the child task is passed into exit_thread(),
however during the process, io_bitmap_exit() nullifies the parent's
io_bitmap rather than the child's.
As copy_thread_tls() has been called ahead of the failure, the reference
count on the calling thread's io_bitmap is incremented as we would expect.
However, io_bitmap_exit() doesn't accept any arguments, and thus assumes
it should trash the current thread's io_bitmap reference rather than the
child's. This is pretty sneaky in practice, because in all instances but
this one, exit_thread() is called with respect to the current task and
everything works out.
A determined attacker can issue an appropriate ioctl (i.e. KDENABIO) to
get a bitmap allocated, and force a clone3() syscall to fail by passing
in a zeroed clone_args structure. The kernel handles the erroneous struct
and the buggy code path is followed, and even though the parent's reference
to the io_bitmap is trashed, the child still holds a reference and thus
the structure will never be freed.
Fix this by tweaking io_bitmap_exit() and its subroutines to accept a
task_struct argument which to operate on.
Fixes: ea5f1cd7ab ("x86/ioperm: Remove bitmap if all permissions dropped")
Signed-off-by: Jay Lang <jaytlang@mit.edu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable#@vger.kernel.org
Link: https://lkml.kernel.org/r/20200524162742.253727-1-jaytlang@mit.edu
This reverts commit c58c1f8343.
io_uring does do the right thing for this case, and we're still returning
-EAGAIN to userspace for the cases we don't support. Revert this change
to avoid doing endless spins of resubmits.
Cc: stable@vger.kernel.org # v5.6
Reported-by: Bijan Mottahedeh <bijan.mottahedeh@oracle.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
KMSAN reported uninitialized data being written to disk when dumping
core. As a result, several kilobytes of kmalloc memory may be written
to the core file and then read by a non-privileged user.
Reported-by: sam <sunhaoyl@outlook.com>
Signed-off-by: Alexander Potapenko <glider@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Kees Cook <keescook@chromium.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: <stable@vger.kernel.org>
Link: http://lkml.kernel.org/r/20200419100848.63472-1-glider@google.com
Link: https://github.com/google/kmsan/issues/76
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Replace superfluous VM_BUG_ON() with comment about correct usage.
Technically reverts commit 1d148e218a ("mm: add VM_BUG_ON_PAGE() to
page_mapcount()"), but context lines have changed.
Function isolate_migratepages_block() runs some checks out of lru_lock
when choose pages for migration. After checking PageLRU() it checks
extra page references by comparing page_count() and page_mapcount().
Between these two checks page could be removed from lru, freed and taken
by slab.
As a result this race triggers VM_BUG_ON(PageSlab()) in page_mapcount().
Race window is tiny. For certain workload this happens around once a
year.
page:ffffea0105ca9380 count:1 mapcount:0 mapping:ffff88ff7712c180 index:0x0 compound_mapcount: 0
flags: 0x500000000008100(slab|head)
raw: 0500000000008100 dead000000000100 dead000000000200 ffff88ff7712c180
raw: 0000000000000000 0000000080200020 00000001ffffffff 0000000000000000
page dumped because: VM_BUG_ON_PAGE(PageSlab(page))
------------[ cut here ]------------
kernel BUG at ./include/linux/mm.h:628!
invalid opcode: 0000 [#1] SMP NOPTI
CPU: 77 PID: 504 Comm: kcompactd1 Tainted: G W 4.19.109-27 #1
Hardware name: Yandex T175-N41-Y3N/MY81-EX0-Y3N, BIOS R05 06/20/2019
RIP: 0010:isolate_migratepages_block+0x986/0x9b0
The code in isolate_migratepages_block() was added in commit
119d6d59dc ("mm, compaction: avoid isolating pinned pages") before
adding VM_BUG_ON into page_mapcount().
This race has been predicted in 2015 by Vlastimil Babka (see link
below).
[akpm@linux-foundation.org: comment tweaks, per Hugh]
Fixes: 1d148e218a ("mm: add VM_BUG_ON_PAGE() to page_mapcount()")
Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Hugh Dickins <hughd@google.com>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: David Rientjes <rientjes@google.com>
Cc: <stable@vger.kernel.org>
Link: http://lkml.kernel.org/r/159032779896.957378.7852761411265662220.stgit@buzz
Link: https://lore.kernel.org/lkml/557710E1.6060103@suse.cz/
Link: https://lore.kernel.org/linux-mm/158937872515.474360.5066096871639561424.stgit@buzz/T/ (v1)
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When collapse_file() calls try_to_release_page(), it has already isolated
the page: so if releasing buffers happens to fail (as it sometimes does),
remember to putback_lru_page(): otherwise that page is left unreclaimable
and unfreeable, and the file extent uncollapsible.
Fixes: 99cb0dbd47 ("mm,thp: add read-only THP support for (non-shmem) FS")
Signed-off-by: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Song Liu <songliubraving@fb.com>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Rik van Riel <riel@surriel.com>
Cc: <stable@vger.kernel.org> [5.4+]
Link: http://lkml.kernel.org/r/alpine.LSU.2.11.2005231837500.1766@eggly.anvils
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Kmemleak reported many leaks while under memory pressue in,
slots = alloc_slots(pool, gfp);
which is referenced by "zhdr" in init_z3fold_page(),
zhdr->slots = slots;
However, "zhdr" could be gone without freeing slots as the later will be
freed separately when the last "handle" off of "handles" array is freed.
It will be within "slots" which is always aligned.
unreferenced object 0xc000000fdadc1040 (size 104):
comm "oom04", pid 140476, jiffies 4295359280 (age 3454.970s)
hex dump (first 32 bytes):
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
backtrace:
z3fold_zpool_malloc+0x7b0/0xe10
alloc_slots at mm/z3fold.c:214
(inlined by) init_z3fold_page at mm/z3fold.c:412
(inlined by) z3fold_alloc at mm/z3fold.c:1161
(inlined by) z3fold_zpool_malloc at mm/z3fold.c:1735
zpool_malloc+0x34/0x50
zswap_frontswap_store+0x60c/0xda0
zswap_frontswap_store at mm/zswap.c:1093
__frontswap_store+0x128/0x330
swap_writepage+0x58/0x110
pageout+0x16c/0xa40
shrink_page_list+0x1ac8/0x25c0
shrink_inactive_list+0x270/0x730
shrink_lruvec+0x444/0xf30
shrink_node+0x2a4/0x9c0
do_try_to_free_pages+0x158/0x640
try_to_free_pages+0x1bc/0x5f0
__alloc_pages_slowpath.constprop.60+0x4dc/0x15a0
__alloc_pages_nodemask+0x520/0x650
alloc_pages_vma+0xc0/0x420
handle_mm_fault+0x1174/0x1bf0
Signed-off-by: Qian Cai <cai@lca.pw>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Vitaly Wool <vitaly.wool@konsulko.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Link: http://lkml.kernel.org/r/20200522220052.2225-1-cai@lca.pw
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The intermediate result of the old term (4UL * 1024 * 1024 * 1024) is
4 294 967 296 or 0x100000000 which is no problem on 64 bit systems.
The patch does not change the later overall result of 0x100000 for
MAX_DMA32_PFN (after it has been shifted by PAGE_SHIFT). The new
calculation yields the same result, but does not require 64 bit
arithmetic.
On 32 bit systems the old calculation suffers from an arithmetic
overflow in that intermediate term in braces: 4UL aka unsigned long int
is 4 byte wide and an arithmetic overflow happens (the 0x100000000 does
not fit in 4 bytes), the in braces result is truncated to zero, the
following right shift does not alter that, so MAX_DMA32_PFN evaluates to
0 on 32 bit systems.
That wrong value is a problem in a comparision against MAX_DMA32_PFN in
the init code for swiotlb in pci_swiotlb_detect_4gb() to decide if
swiotlb should be active. That comparison yields the opposite result,
when compiling on 32 bit systems.
This was not possible before
1b7e03ef75 ("x86, NUMA: Enable emulation on 32bit too")
when that MAX_DMA32_PFN was first made visible to x86_32 (and which
landed in v3.0).
In practice this wasn't a problem, unless CONFIG_SWIOTLB is active on
x86-32.
However if one has set CONFIG_IOMMU_INTEL, since
c5a5dc4cbb ("iommu/vt-d: Don't switch off swiotlb if bounce page is used")
there's a dependency on CONFIG_SWIOTLB, which was not necessarily
active before. That landed in v5.4, where we noticed it in the fli4l
Linux distribution. We have CONFIG_IOMMU_INTEL active on both 32 and 64
bit kernel configs there (I could not find out why, so let's just say
historical reasons).
The effect is at boot time 64 MiB (default size) were allocated for
bounce buffers now, which is a noticeable amount of memory on small
systems like pcengines ALIX 2D3 with 256 MiB memory, which are still
frequently used as home routers.
We noticed this effect when migrating from kernel v4.19 (LTS) to v5.4
(LTS) in fli4l and got that kernel messages for example:
Linux version 5.4.22 (buildroot@buildroot) (gcc version 7.3.0 (Buildroot 2018.02.8)) #1 SMP Mon Nov 26 23:40:00 CET 2018
…
Memory: 183484K/261756K available (4594K kernel code, 393K rwdata, 1660K rodata, 536K init, 456K bss , 78272K reserved, 0K cma-reserved, 0K highmem)
…
PCI-DMA: Using software bounce buffering for IO (SWIOTLB)
software IO TLB: mapped [mem 0x0bb78000-0x0fb78000] (64MB)
The initial analysis and the suggested fix was done by user 'sourcejedi'
at stackoverflow and explicitly marked as GPLv2 for inclusion in the
Linux kernel:
https://unix.stackexchange.com/a/520525/50007
The new calculation, which does not suffer from that overflow, is the
same as for arch/mips now as suggested by Robin Murphy.
The fix was tested by fli4l users on round about two dozen different
systems, including both 32 and 64 bit archs, bare metal and virtualized
machines.
[ bp: Massage commit message. ]
Fixes: 1b7e03ef75 ("x86, NUMA: Enable emulation on 32bit too")
Reported-by: Alan Jenkins <alan.christopher.jenkins@gmail.com>
Suggested-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Alexander Dahl <post@lespocky.de>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: stable@vger.kernel.org
Link: https://unix.stackexchange.com/q/520065/50007
Link: https://web.nettworks.org/bugs/browse/FFL-2560
Link: https://lkml.kernel.org/r/20200526175749.20742-1-post@lespocky.de
kobject_init_and_add() takes reference even when it fails.
If this function returns an error, kobject_put() must be called to
properly clean up the memory associated with the object. Previous
commit "b8eb718348b8" fixed a similar problem.
Fixes: 07699f9a7c ("bonding: add sysfs /slave dir for bond slave devices.")
Signed-off-by: Qiushi Wu <wu000273@umn.edu>
Acked-by: Jay Vosburgh <jay.vosburgh@canonical.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Pablo Neira Ayuso says:
====================
Netfilter fixes for net
The following patchset contains Netfilter fixes for net:
1) Uninitialized when used in __nf_conntrack_update(), from
Nathan Chancellor.
2) Comparison of unsigned expression in nf_confirm_cthelper().
3) Remove 'const' type qualifier with no effect.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
The commit 0ebeea8ca8 ("bpf: Restrict bpf_probe_read{, str}() only
to archs where they work") caused that bpf_probe_read{, str}() functions
were not longer available on architectures where the same logical address
might have different content in kernel and user memory mapping. These
architectures should use probe_read_{user,kernel}_str helpers.
For backward compatibility, the problematic functions are still available
on architectures where the user and kernel address spaces are not
overlapping. This is defined CONFIG_ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE.
At the moment, these backward compatible functions are enabled only on x86_64,
arm, and arm64. Let's do it also on powerpc that has the non overlapping
address space as well.
Fixes: 0ebeea8ca8 ("bpf: Restrict bpf_probe_read{, str}() only to archs where they work")
Signed-off-by: Petr Mladek <pmladek@suse.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/lkml/20200527122844.19524-1-pmladek@suse.com
Baikal-T1 SoC provides an embedded process, voltage and temperature
sensor to monitor an internal SoC environment (chip temperature, supply
voltage and process monitor) and on time detect critical situations,
which may cause the system instability and even damages. The IP-block
is based on the Analog Bits PVT sensor, but is equipped with a
dedicated control wrapper, which provides a MMIO registers-based access
to the sensor core functionality (APB3-bus based) and exposes an
additional functions like thresholds/data ready interrupts, its status
and masks, measurements timeout. All of these is used to create a hwmon
driver being added to the kernel by this commit.
The driver implements support for the hardware monitoring capabilities
of Baikal-T1 process, voltage and temperature sensors. PVT IP-core
consists of one temperature and four voltage sensors, each of which is
implemented as a dedicated hwmon channel config.
The driver can optionally provide the hwmon alarms for each sensor the
PVT controller supports. The alarms functionality is made compile-time
configurable due to the hardware interface implementation peculiarity,
which is connected with an ability to convert data from only one sensor
at a time. Additional limitation is that the controller performs the
thresholds checking synchronously with the data conversion procedure.
Due to these limitations in order to have the hwmon alarms
automatically detected the driver code must switch from one sensor to
another, read converted data and manually check the threshold status
bits. Depending on the measurements timeout settings this design may
cause additional burden on the system performance. By default if the
alarms kernel config is disabled the data conversion is performed by
the driver on demand when read operation is requested via corresponding
_input-file.
Co-developed-by: Maxim Kaurkin <maxim.kaurkin@baikalelectronics.ru>
Signed-off-by: Maxim Kaurkin <maxim.kaurkin@baikalelectronics.ru>
Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
Cc: Alexey Malahov <Alexey.Malahov@baikalelectronics.ru>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: linux-mips@vger.kernel.org
Cc: devicetree@vger.kernel.org
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
For hwmon drivers using the hwmon_device_register_with_info() API, it
is desirable to have a generic notification mechanism available. This
mechanism can be used to notify userspace as well as the thermal
subsystem if the driver experiences any events, such as warning or
critical alarms.
Implement hwmon_notify_event() to provide this mechanism. The function
generates a sysfs event and a udev event. If the device is registered
with the thermal subsystem and the event is associated with a temperature
sensor, also notify the thermal subsystem that a thermal event occurred.
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
Cc: Maxim Kaurkin <Maxim.Kaurkin@baikalelectronics.ru>
Cc: Alexey Malahov <Alexey.Malahov@baikalelectronics.ru>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: linux-mips@vger.kernel.org
Cc: devicetree@vger.kernel.org
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Baikal-T1 SoC is equipped with an embedded process, voltage and
temperature sensor to monitor the chip internal environment like
temperature, supply voltage and transistors performance.
This bindings describes the external Baikal-T1 PVT control interfaces
like MMIO registers space, interrupt request number and clocks source.
These are then used by the corresponding hwmon device driver to
implement the sysfs files-based access to the sensors functionality.
Co-developed-by: Maxim Kaurkin <maxim.kaurkin@baikalelectronics.ru>
Signed-off-by: Maxim Kaurkin <maxim.kaurkin@baikalelectronics.ru>
Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
Reviewed-by: Rob Herring <robh@kernel.org>
Cc: Alexey Malahov <Alexey.Malahov@baikalelectronics.ru>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: linux-mips@vger.kernel.org
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
There is ecspi ERR009165 on i.mx6/7 soc family, which cause FIFO
transfer to be send twice in DMA mode. Please get more information from:
https://www.nxp.com/docs/en/errata/IMX6DQCE.pdf. The workaround is adding
new sdma ram script which works in XCH mode as PIO inside sdma instead
of SMC mode, meanwhile, 'TX_THRESHOLD' should be 0. The issue should be
exist on all legacy i.mx6/7 soc family before i.mx6ul.
NXP fix this design issue from i.mx6ul, so newer chips including i.mx6ul/
6ull/6sll do not need this workaroud anymore. All other i.mx6/7/8 chips
still need this workaroud. This patch set add new 'fsl,imx6ul-ecspi'
for ecspi driver and 'ecspi_fixed' in sdma driver to choose if need errata
or not.
The first two reverted patches should be the same issue, though, it
seems 'fixed' by changing to other shp script. Hope Sean or Sascha could
have the chance to test this patch set if could fix their issues.
Besides, enable sdma support for i.mx8mm/8mq and fix ecspi1 not work
on i.mx8mm because the event id is zero.
PS:
Please get sdma firmware from below linux-firmware and copy it to your
local rootfs /lib/firmware/imx/sdma.
https://git.kernel.org/pub/scm/linux/kernel/git/firmware/linux-firmware.git/tree/imx/sdma
v2:
1.Add commit log for reverted patches.
2.Add comment for 'ecspi_fixed' in sdma driver.
3.Add 'fsl,imx6sll-ecspi' compatible instead of 'fsl,imx6ul-ecspi'
rather than remove.
v3:
1.Confirm with design team make sure ERR009165 fixed on i.mx6ul/i.mx6ull
/i.mx6sll, not fixed on i.mx8m/8mm and other i.mx6/7 legacy chips.
Correct dts related dts patch in v2.
2.Clean eratta information in binding doc and new 'tx_glitch_fixed' flag
in spi-imx driver to state ERR009165 fixed or not.
3.Enlarge burst size to fifo size for tx since tx_wml set to 0 in the
errata workaroud, thus improve performance as possible.
v4:
1.Add Ack tag from Mark and Vinod
2.Remove checking 'event_id1' zero as 'event_id0'.
v5:
1.Add the last patch for compatible with the current uart driver which
using rom script, so both uart ram script and rom script supported
in latest firmware, by default uart rom script used. UART driver
will be broken without this patch.
v6:
1.Resend after rebase the latest next branch.
2.Remove below No.13~No.15 patches of v5 because they were mergered.
ARM: dts: imx6ul: add dma support on ecspi
ARM: dts: imx6sll: correct sdma compatible
arm64: defconfig: Enable SDMA on i.mx8mq/8mm
3.Revert "dmaengine: imx-sdma: fix context cache" since
'context_loaded' removed.
v7:
1.Put the last patch 13/13 'Revert "dmaengine: imx-sdma: fix context
cache"' to the ahead of 03/13 'Revert "dmaengine: imx-sdma: refine
to load context only once" so that no building waring during comes out
during bisect.
2.Address Sascha's comments, including eliminating any i.mx6sx in this
series, adding new 'is_imx6ul_ecspi()' instead imx in imx51 and taking
care SMC bit for PIO.
3.Add back missing 'Reviewed-by' tag on 08/15(v5):09/13(v7)
'spi: imx: add new i.mx6ul compatible name in binding doc'
v8:
1.remove 0003-Revert-dmaengine-imx-sdma-fix-context-cache.patch and merge
it into 04/13 of v7
2.add 0005-spi-imx-fallback-to-PIO-if-dma-setup-failure.patch for no any
ecspi function broken even if sdma firmware not updated.
3.merge 'tx.dst_maxburst' changes in the two continous patches into one
patch to avoid confusion.
4.fix typo 'duplicated'.
Robin Gong (13):
Revert "ARM: dts: imx6q: Use correct SDMA script for SPI5 core"
Revert "ARM: dts: imx6: Use correct SDMA script for SPI cores"
Revert "dmaengine: imx-sdma: refine to load context only once"
dmaengine: imx-sdma: remove duplicated sdma_load_context
spi: imx: fallback to PIO if dma setup failure
dmaengine: imx-sdma: add mcu_2_ecspi script
spi: imx: fix ERR009165
spi: imx: remove ERR009165 workaround on i.mx6ul
spi: imx: add new i.mx6ul compatible name in binding doc
dmaengine: imx-sdma: remove ERR009165 on i.mx6ul
dma: imx-sdma: add i.mx6ul compatible name
dmaengine: imx-sdma: fix ecspi1 rx dma not work on i.mx8mm
dmaengine: imx-sdma: add uart rom script
.../devicetree/bindings/dma/fsl-imx-sdma.txt | 1 +
.../devicetree/bindings/spi/fsl-imx-cspi.txt | 1 +
arch/arm/boot/dts/imx6q.dtsi | 2 +-
arch/arm/boot/dts/imx6qdl.dtsi | 8 +-
drivers/dma/imx-sdma.c | 67 ++++++++++------
drivers/spi/spi-imx.c | 92 +++++++++++++++++++---
include/linux/platform_data/dma-imx-sdma.h | 8 +-
7 files changed, 135 insertions(+), 44 deletions(-)
--
2.7.4
_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.orghttp://lists.infradead.org/mailman/listinfo/linux-arm-kernel
pm_runtime_get_sync() increments the runtime PM usage counter even
when it returns an error code. Thus a pairing decrement is needed on
the error handling path to keep the counter balanced.
Signed-off-by: Dinghao Liu <dinghao.liu@zju.edu.cn>
Link: https://lore.kernel.org/r/20200523124758.28604-1-dinghao.liu@zju.edu.cn
Signed-off-by: Mark Brown <broonie@kernel.org>
pm_runtime_get_sync() increments the runtime PM usage counter even
when it returns an error code. Thus a pairing decrement is needed on
the error handling path to keep the counter balanced.
Signed-off-by: Dinghao Liu <dinghao.liu@zju.edu.cn>
Link: https://lore.kernel.org/r/20200523122909.25247-1-dinghao.liu@zju.edu.cn
Signed-off-by: Mark Brown <broonie@kernel.org>
pm_runtime_get_sync() increments the runtime PM usage counter even
when it returns an error code. Thus a pairing decrement is needed on
the error handling path to keep the counter balanced.
Signed-off-by: Dinghao Liu <dinghao.liu@zju.edu.cn>
Link: https://lore.kernel.org/r/20200523125704.30300-1-dinghao.liu@zju.edu.cn
Signed-off-by: Mark Brown <broonie@kernel.org>
Fallback to PIO in case dma setup failed. For example, sdma firmware not
updated but ERR009165 workaroud added in kernel.
Signed-off-by: Robin Gong <yibin.gong@nxp.com>
Acked-by: Sascha Hauer <s.hauer@pengutronix.de>
Link: https://lore.kernel.org/r/1590006865-20900-6-git-send-email-yibin.gong@nxp.com
Signed-off-by: Mark Brown <broonie@kernel.org>
If boot_secondary() was successful, and cpu_online() was an error in
__cpu_up(), -EIO was returned, but 0 is returned by commit d22b115cbf
("arm64/kernel: Simplify __cpu_up() by bailing out early").
Therefore, bringup_wait_for_ap() causes the primary core to wait for a
long time, which may cause boot failure.
This commit sets -EIO to return code under the same conditions.
Fixes: d22b115cbf ("arm64/kernel: Simplify __cpu_up() by bailing out early")
Signed-off-by: Nobuhiro Iwamatsu <nobuhiro1.iwamatsu@toshiba.co.jp>
Tested-by: Yuji Ishikawa <yuji2.ishikawa@toshiba.co.jp>
Acked-by: Will Deacon <will@kernel.org>
Cc: Gavin Shan <gshan@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/r/20200527233457.2531118-1-nobuhiro1.iwamatsu@toshiba.co.jp
[catalin.marinas@arm.com: return -EIO at the end of the function]
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
In order to be compatible with devices of different versions, V1 in the
accelerator driver is now isolated, and other versions are the previous
V2 processing flow.
Signed-off-by: Weili Qian <qianweili@huawei.com>
Signed-off-by: Shukun Tan <tanshukun1@huawei.com>
Reviewed-by: Zhou Wang <wangzhou1@hisilicon.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Now, in crypto-engine, if hardware queue is full (-ENOSPC),
requeue request regardless of MAY_BACKLOG flag.
If hardware throws any other error code (like -EIO, -EINVAL,
-ENOMEM, etc.) only MAY_BACKLOG requests are enqueued back into
crypto-engine's queue, since the others can be dropped.
The latter case can be fatal error, so those cannot be recovered from.
For example, in CAAM driver, -EIO is returned in case the job descriptor
is broken, so there is no possibility to fix the job descriptor.
Therefore, these errors might be fatal error, so we shouldn’t
requeue the request. This will just be pass back and forth between
crypto-engine and hardware.
Fixes: 6a89f492f8 ("crypto: engine - support for parallel requests based on retry mechanism")
Signed-off-by: Iuliana Prodan <iuliana.prodan@nxp.com>
Reported-by: Horia Geantă <horia.geanta@nxp.com>
Reviewed-by: Horia Geantă <horia.geanta@nxp.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Put the rseq_syscall check point at the prologue of the syscall
will break the a0 ... a7. This will casue system call bug when
DEBUG_RSEQ is enabled.
So move it to the epilogue of syscall, but before syscall_trace.
Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
There is no fixup or feature in the patch, we only cleanup with:
- Remove unnecessary reg used (r11, r12), just use r9 & r10 &
syscallid regs as temp useage.
- Add _TIF_SYSCALL_WORK and _TIF_WORK_MASK to gather macros.
Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
Current implementation could destory a4 & a5 when strace, so we need to get them
from pt_regs by SAVE_ALL.
Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
When connected mode is set, and we have connected and datagram traffic in
parallel, ipoib might crash with double free of datagram skb.
The current mechanism assumes that the order in the completion queue is
the same as the order of sent packets for all QPs. Order is kept only for
specific QP, in case of mixed UD and CM traffic we have few QPs (one UD and
few CM's) in parallel.
The problem:
----------------------------------------------------------
Transmit queue:
-----------------
UD skb pointer kept in queue itself, CM skb kept in spearate queue and
uses transmit queue as a placeholder to count the number of total
transmitted packets.
0 1 2 3 4 5 6 7 8 9 10 11 12 13 .........127
------------------------------------------------------------
NL ud1 UD2 CM1 ud3 cm2 cm3 ud4 cm4 ud5 NL NL NL ...........
------------------------------------------------------------
^ ^
tail head
Completion queue (problematic scenario) - the order not the same as in
the transmit queue:
1 2 3 4 5 6 7 8 9
------------------------------------
ud1 CM1 UD2 ud3 cm2 cm3 ud4 cm4 ud5
------------------------------------
1. CM1 'wc' processing
- skb freed in cm separate ring.
- tx_tail of transmit queue increased although UD2 is not freed.
Now driver assumes UD2 index is already freed and it could be used for
new transmitted skb.
0 1 2 3 4 5 6 7 8 9 10 11 12 13 .........127
------------------------------------------------------------
NL NL UD2 CM1 ud3 cm2 cm3 ud4 cm4 ud5 NL NL NL ...........
------------------------------------------------------------
^ ^ ^
(Bad)tail head
(Bad - Could be used for new SKB)
In this case (due to heavy load) UD2 skb pointer could be replaced by new
transmitted packet UD_NEW, as the driver assumes its free. At this point
we will have to process two 'wc' with same index but we have only one
pointer to free.
During second attempt to free the same skb we will have NULL pointer
exception.
2. UD2 'wc' processing
- skb freed according the index we got from 'wc', but it was already
overwritten by mistake. So actually the skb that was released is the
skb of the new transmitted packet and not the original one.
3. UD_NEW 'wc' processing
- attempt to free already freed skb. NUll pointer exception.
The fix:
-----------------------------------------------------------------------
The fix is to stop using the UD ring as a placeholder for CM packets, the
cyclic ring variables tx_head and tx_tail will manage the UD tx_ring, a
new cyclic variables global_tx_head and global_tx_tail are introduced for
managing and counting the overall outstanding sent packets, then the send
queue will be stopped and waken based on these variables only.
Note that no locking is needed since global_tx_head is updated in the xmit
flow and global_tx_tail is updated in the NAPI flow only. A previous
attempt tried to use one variable to count the outstanding sent packets,
but it did not work since xmit and NAPI flows can run at the same time and
the counter will be updated wrongly. Thus, we use the same simple cyclic
head and tail scheme that we have today for the UD tx_ring.
Fixes: 2c104ea683 ("IB/ipoib: Get rid of the tx_outstanding variable in all modes")
Link: https://lore.kernel.org/r/20200527134705.480068-1-leon@kernel.org
Signed-off-by: Valentine Fatiev <valentinef@mellanox.com>
Signed-off-by: Alaa Hleihel <alaa@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Acked-by: Doug Ledford <dledford@redhat.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
[Why]
If VUPDATE_END is before VUPDATE_START the delay calculated can become
very large, causing a soft hang.
[How]
Take the absolute value of the difference between START and END.
Signed-off-by: Aric Cyr <aric.cyr@amd.com>
Reviewed-by: Nicholas Kazlauskas <Nicholas.Kazlauskas@amd.com>
Acked-by: Qingqing Zhuo <qingqing.zhuo@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org
get_cursor_position already handles the case where the cursor has
negative off-screen coordinates by not setting
dc_cursor_position.enabled.
Signed-off-by: Simon Ser <contact@emersion.fr>
Fixes: 626bf90fe0 ("drm/amd/display: add basic atomic check for cursor plane")
Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: Nicholas Kazlauskas <nicholas.kazlauskas@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org
Be there a platform with the following layout:
Regular NIC
|
+----> DSA master for switch port
|
+----> DSA master for another switch port
After changing DSA back to static lockdep class keys in commit
1a33e10e4a ("net: partially revert dynamic lockdep key changes"), this
kernel splat can be seen:
[ 13.361198] ============================================
[ 13.366524] WARNING: possible recursive locking detected
[ 13.371851] 5.7.0-rc4-02121-gc32a05ecd7af-dirty #988 Not tainted
[ 13.377874] --------------------------------------------
[ 13.383201] swapper/0/0 is trying to acquire lock:
[ 13.388004] ffff0000668ff298 (&dsa_slave_netdev_xmit_lock_key){+.-.}-{2:2}, at: __dev_queue_xmit+0x84c/0xbe0
[ 13.397879]
[ 13.397879] but task is already holding lock:
[ 13.403727] ffff0000661a1698 (&dsa_slave_netdev_xmit_lock_key){+.-.}-{2:2}, at: __dev_queue_xmit+0x84c/0xbe0
[ 13.413593]
[ 13.413593] other info that might help us debug this:
[ 13.420140] Possible unsafe locking scenario:
[ 13.420140]
[ 13.426075] CPU0
[ 13.428523] ----
[ 13.430969] lock(&dsa_slave_netdev_xmit_lock_key);
[ 13.435946] lock(&dsa_slave_netdev_xmit_lock_key);
[ 13.440924]
[ 13.440924] *** DEADLOCK ***
[ 13.440924]
[ 13.446860] May be due to missing lock nesting notation
[ 13.446860]
[ 13.453668] 6 locks held by swapper/0/0:
[ 13.457598] #0: ffff800010003de0 ((&idev->mc_ifc_timer)){+.-.}-{0:0}, at: call_timer_fn+0x0/0x400
[ 13.466593] #1: ffffd4d3fb478700 (rcu_read_lock){....}-{1:2}, at: mld_sendpack+0x0/0x560
[ 13.474803] #2: ffffd4d3fb478728 (rcu_read_lock_bh){....}-{1:2}, at: ip6_finish_output2+0x64/0xb10
[ 13.483886] #3: ffffd4d3fb478728 (rcu_read_lock_bh){....}-{1:2}, at: __dev_queue_xmit+0x6c/0xbe0
[ 13.492793] #4: ffff0000661a1698 (&dsa_slave_netdev_xmit_lock_key){+.-.}-{2:2}, at: __dev_queue_xmit+0x84c/0xbe0
[ 13.503094] #5: ffffd4d3fb478728 (rcu_read_lock_bh){....}-{1:2}, at: __dev_queue_xmit+0x6c/0xbe0
[ 13.512000]
[ 13.512000] stack backtrace:
[ 13.516369] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.7.0-rc4-02121-gc32a05ecd7af-dirty #988
[ 13.530421] Call trace:
[ 13.532871] dump_backtrace+0x0/0x1d8
[ 13.536539] show_stack+0x24/0x30
[ 13.539862] dump_stack+0xe8/0x150
[ 13.543271] __lock_acquire+0x1030/0x1678
[ 13.547290] lock_acquire+0xf8/0x458
[ 13.550873] _raw_spin_lock+0x44/0x58
[ 13.554543] __dev_queue_xmit+0x84c/0xbe0
[ 13.558562] dev_queue_xmit+0x24/0x30
[ 13.562232] dsa_slave_xmit+0xe0/0x128
[ 13.565988] dev_hard_start_xmit+0xf4/0x448
[ 13.570182] __dev_queue_xmit+0x808/0xbe0
[ 13.574200] dev_queue_xmit+0x24/0x30
[ 13.577869] neigh_resolve_output+0x15c/0x220
[ 13.582237] ip6_finish_output2+0x244/0xb10
[ 13.586430] __ip6_finish_output+0x1dc/0x298
[ 13.590709] ip6_output+0x84/0x358
[ 13.594116] mld_sendpack+0x2bc/0x560
[ 13.597786] mld_ifc_timer_expire+0x210/0x390
[ 13.602153] call_timer_fn+0xcc/0x400
[ 13.605822] run_timer_softirq+0x588/0x6e0
[ 13.609927] __do_softirq+0x118/0x590
[ 13.613597] irq_exit+0x13c/0x148
[ 13.616918] __handle_domain_irq+0x6c/0xc0
[ 13.621023] gic_handle_irq+0x6c/0x160
[ 13.624779] el1_irq+0xbc/0x180
[ 13.627927] cpuidle_enter_state+0xb4/0x4d0
[ 13.632120] cpuidle_enter+0x3c/0x50
[ 13.635703] call_cpuidle+0x44/0x78
[ 13.639199] do_idle+0x228/0x2c8
[ 13.642433] cpu_startup_entry+0x2c/0x48
[ 13.646363] rest_init+0x1ac/0x280
[ 13.649773] arch_call_rest_init+0x14/0x1c
[ 13.653878] start_kernel+0x490/0x4bc
Lockdep keys themselves were added in commit ab92d68fc2 ("net: core:
add generic lockdep keys"), and it's very likely that this splat existed
since then, but I have no real way to check, since this stacked platform
wasn't supported by mainline back then.
>From Taehee's own words:
This patch was considered that all stackable devices have LLTX flag.
But the dsa doesn't have LLTX, so this splat happened.
After this patch, dsa shares the same lockdep class key.
On the nested dsa interface architecture, which you illustrated,
the same lockdep class key will be used in __dev_queue_xmit() because
dsa doesn't have LLTX.
So that lockdep detects deadlock because the same lockdep class key is
used recursively although actually the different locks are used.
There are some ways to fix this problem.
1. using NETIF_F_LLTX flag.
If possible, using the LLTX flag is a very clear way for it.
But I'm so sorry I don't know whether the dsa could have LLTX or not.
2. using dynamic lockdep again.
It means that each interface uses a separate lockdep class key.
So, lockdep will not detect recursive locking.
But this way has a problem that it could consume lockdep class key
too many.
Currently, lockdep can have 8192 lockdep class keys.
- you can see this number with the following command.
cat /proc/lockdep_stats
lock-classes: 1251 [max: 8192]
...
The [max: 8192] means that the maximum number of lockdep class keys.
If too many lockdep class keys are registered, lockdep stops to work.
So, using a dynamic(separated) lockdep class key should be considered
carefully.
In addition, updating lockdep class key routine might have to be existing.
(lockdep_register_key(), lockdep_set_class(), lockdep_unregister_key())
3. Using lockdep subclass.
A lockdep class key could have 8 subclasses.
The different subclass is considered different locks by lockdep
infrastructure.
But "lock-classes" is not counted by subclasses.
So, it could avoid stopping lockdep infrastructure by an overflow of
lockdep class keys.
This approach should also have an updating lockdep class key routine.
(lockdep_set_subclass())
4. Using nonvalidate lockdep class key.
The lockdep infrastructure supports nonvalidate lockdep class key type.
It means this lockdep is not validated by lockdep infrastructure.
So, the splat will not happen but lockdep couldn't detect real deadlock
case because lockdep really doesn't validate it.
I think this should be used for really special cases.
(lockdep_set_novalidate_class())
Further discussion here:
https://patchwork.ozlabs.org/project/netdev/patch/20200503052220.4536-2-xiyou.wangcong@gmail.com/
There appears to be no negative side-effect to declaring lockless TX for
the DSA virtual interfaces, which means they handle their own locking.
So that's what we do to make the splat go away.
Patch tested in a wide variety of cases: unicast, multicast, PTP, etc.
Fixes: ab92d68fc2 ("net: core: add generic lockdep keys")
Suggested-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
copy the corresponding pieces of init_fpstate into the gaps instead.
Cc: stable@kernel.org
Tested-by: Alexander Potapenko <glider@google.com>
Acked-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
