Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.
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Pull ext4 bug fixes from Ted Ts'o:
"Ext4 bug fixes, including a regression fix"
* tag 'ext4_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
ext4: clarify impact of 'commit' mount option
ext4: fix unused-but-set-variable warning in ext4_add_entry()
jbd2: fix kernel-doc notation warning
ext4: use RCU API in debug_print_tree
ext4: validate the debug_want_extra_isize mount option at parse time
ext4: reserve revoke credits in __ext4_new_inode
ext4: unlock on error in ext4_expand_extra_isize()
ext4: optimize __ext4_check_dir_entry()
ext4: check for directory entries too close to block end
ext4: fix ext4_empty_dir() for directories with holes
Pull block fixes from Jens Axboe:
"Let's try this one again, this time without the compat_ioctl changes.
We've got those fixed up, but that can go out next week.
This contains:
- block queue flush lockdep annotation (Bart)
- Type fix for bsg_queue_rq() (Bart)
- Three dasd fixes (Stefan, Jan)
- nbd deadlock fix (Mike)
- Error handling bio user map fix (Yang)
- iocost fix (Tejun)
- sbitmap waitqueue addition fix that affects the kyber IO scheduler
(David)"
* tag 'block-5.5-20191221' of git://git.kernel.dk/linux-block:
sbitmap: only queue kyber's wait callback if not already active
block: fix memleak when __blk_rq_map_user_iov() is failed
s390/dasd: fix typo in copyright statement
s390/dasd: fix memleak in path handling error case
s390/dasd/cio: Interpret ccw_device_get_mdc return value correctly
block: Fix a lockdep complaint triggered by request queue flushing
block: Fix the type of 'sts' in bsg_queue_rq()
block: end bio with BLK_STS_AGAIN in case of non-mq devs and REQ_NOWAIT
nbd: fix shutdown and recv work deadlock v2
iocost: over-budget forced IOs should schedule async delay
The description of 'commit' mount option dates back to ext3 times.
Update the description to match current meaning for ext4.
Reported-by: Paul Richards <paul.richards@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20191218111210.14161-1-jack@suse.cz
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Pull KVM fixes from Paolo Bonzini:
"PPC:
- Fix a bug where we try to do an ultracall on a system without an
ultravisor
KVM:
- Fix uninitialised sysreg accessor
- Fix handling of demand-paged device mappings
- Stop spamming the console on IMPDEF sysregs
- Relax mappings of writable memslots
- Assorted cleanups
MIPS:
- Now orphan, James Hogan is stepping down
x86:
- MAINTAINERS change, so long Radim and thanks for all the fish
- supported CPUID fixes for AMD machines without SPEC_CTRL"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
MAINTAINERS: remove Radim from KVM maintainers
MAINTAINERS: Orphan KVM for MIPS
kvm: x86: Host feature SSBD doesn't imply guest feature AMD_SSBD
kvm: x86: Host feature SSBD doesn't imply guest feature SPEC_CTRL_SSBD
KVM: PPC: Book3S HV: Don't do ultravisor calls on systems without ultravisor
KVM: arm/arm64: Properly handle faulting of device mappings
KVM: arm64: Ensure 'params' is initialised when looking up sys register
KVM: arm/arm64: Remove excessive permission check in kvm_arch_prepare_memory_region
KVM: arm64: Don't log IMP DEF sysreg traps
KVM: arm64: Sanely ratelimit sysreg messages
KVM: arm/arm64: vgic: Use wrapper function to lock/unlock all vcpus in kvm_vgic_create()
KVM: arm/arm64: vgic: Fix potential double free dist->spis in __kvm_vgic_destroy()
KVM: arm/arm64: Get rid of unused arg in cpu_init_hyp_mode()
Under heavy loads where the kyber I/O scheduler hits the token limits for
its scheduling domains, kyber can become stuck. When active requests
complete, kyber may not be woken up leaving the I/O requests in kyber
stuck.
This stuck state is due to a race condition with kyber and the sbitmap
functions it uses to run a callback when enough requests have completed.
The running of a sbt_wait callback can race with the attempt to insert the
sbt_wait. Since sbitmap_del_wait_queue removes the sbt_wait from the list
first then sets the sbq field to NULL, kyber can see the item as not on a
list but the call to sbitmap_add_wait_queue will see sbq as non-NULL. This
results in the sbt_wait being inserted onto the wait list but ws_active
doesn't get incremented. So the sbitmap queue does not know there is a
waiter on a wait list.
Since sbitmap doesn't think there is a waiter, kyber may never be
informed that there are domain tokens available and the I/O never advances.
With the sbt_wait on a wait list, kyber believes it has an active waiter
so cannot insert a new waiter when reaching the domain's full state.
This race can be fixed by only adding the sbt_wait to the queue if the
sbq field is NULL. If sbq is not NULL, there is already an action active
which will trigger the re-running of kyber. Let it run and add the
sbt_wait to the wait list if still needing to wait.
Reviewed-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: David Jeffery <djeffery@redhat.com>
Reported-by: John Pittman <jpittman@redhat.com>
Tested-by: John Pittman <jpittman@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Warning is found when compile with "-Wunused-but-set-variable":
fs/ext4/namei.c: In function ‘ext4_add_entry’:
fs/ext4/namei.c:2167:23: warning: variable ‘sbi’ set but not used
[-Wunused-but-set-variable]
struct ext4_sb_info *sbi;
^~~
Fix this by moving the variable @sbi under CONFIG_UNICODE.
Signed-off-by: Yunfeng Ye <yeyunfeng@huawei.com>
Reviewed-by: Ritesh Harjani <riteshh@linux.ibm.com>
Link: https://lore.kernel.org/r/cb5eb904-224a-9701-c38f-cb23514b1fff@huawei.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Pull RISC-V fixes from Paul Walmsley:
"Several fixes, and one cleanup, for RISC-V.
Fixes:
- Fix an error in a Kconfig file that resulted in an undefined
Kconfig option "CONFIG_CONFIG_MMU"
- Fix undefined Kconfig option "CONFIG_CONFIG_MMU"
- Fix scratch register clearing in M-mode (affects nommu users)
- Fix a mismerge on my part that broke the build for
CONFIG_SPARSEMEM_VMEMMAP users
Cleanup:
- Move SiFive L2 cache-related code to drivers/soc, per request"
* tag 'riscv/for-v5.5-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux:
riscv: move sifive_l2_cache.c to drivers/soc
riscv: define vmemmap before pfn_to_page calls
riscv: fix scratch register clearing in M-mode.
riscv: Fix use of undefined config option CONFIG_CONFIG_MMU
PPC KVM fix for 5.5
- Fix a bug where we try to do an ultracall on a system without an
ultravisor.
When I doing fuzzy test, get the memleak report:
BUG: memory leak
unreferenced object 0xffff88837af80000 (size 4096):
comm "memleak", pid 3557, jiffies 4294817681 (age 112.499s)
hex dump (first 32 bytes):
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
20 00 00 00 10 01 00 00 00 00 00 00 01 00 00 00 ...............
backtrace:
[<000000001c894df8>] bio_alloc_bioset+0x393/0x590
[<000000008b139a3c>] bio_copy_user_iov+0x300/0xcd0
[<00000000a998bd8c>] blk_rq_map_user_iov+0x2f1/0x5f0
[<000000005ceb7f05>] blk_rq_map_user+0xf2/0x160
[<000000006454da92>] sg_common_write.isra.21+0x1094/0x1870
[<00000000064bb208>] sg_write.part.25+0x5d9/0x950
[<000000004fc670f6>] sg_write+0x5f/0x8c
[<00000000b0d05c7b>] __vfs_write+0x7c/0x100
[<000000008e177714>] vfs_write+0x1c3/0x500
[<0000000087d23f34>] ksys_write+0xf9/0x200
[<000000002c8dbc9d>] do_syscall_64+0x9f/0x4f0
[<00000000678d8e9a>] entry_SYSCALL_64_after_hwframe+0x49/0xbe
If __blk_rq_map_user_iov() is failed in blk_rq_map_user_iov(),
the bio(s) which is allocated before this failing will leak. The
refcount of the bio(s) is init to 1 and increased to 2 by calling
bio_get(), but __blk_rq_unmap_user() only decrease it to 1, so
the bio cannot be freed. Fix it by calling blk_rq_unmap_user().
Reviewed-by: Bob Liu <bob.liu@oracle.com>
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Fix kernel-doc warning by inserting a beginning '*' character
for the kernel-doc line.
../include/linux/jbd2.h:461: warning: bad line: journal. These are dirty buffers and revoke descriptor blocks.
Link: https://lore.kernel.org/r/53e3ce27-ceae-560d-0fd4-f95728a33e12@infradead.org
Cc: stable@kernel.org
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Pull networking fixes from David Miller:
1) Several nf_flow_table_offload fixes from Pablo Neira Ayuso,
including adding a missing ipv6 match description.
2) Several heap overflow fixes in mwifiex from qize wang and Ganapathi
Bhat.
3) Fix uninit value in bond_neigh_init(), from Eric Dumazet.
4) Fix non-ACPI probing of nxp-nci, from Stephan Gerhold.
5) Fix use after free in tipc_disc_rcv(), from Tuong Lien.
6) Enforce limit of 33 tail calls in mips and riscv JIT, from Paul
Chaignon.
7) Multicast MAC limit test is off by one in qede, from Manish Chopra.
8) Fix established socket lookup race when socket goes from
TCP_ESTABLISHED to TCP_LISTEN, because there lacks an intervening
RCU grace period. From Eric Dumazet.
9) Don't send empty SKBs from tcp_write_xmit(), also from Eric Dumazet.
10) Fix active backup transition after link failure in bonding, from
Mahesh Bandewar.
11) Avoid zero sized hash table in gtp driver, from Taehee Yoo.
12) Fix wrong interface passed to ->mac_link_up(), from Russell King.
13) Fix DSA egress flooding settings in b53, from Florian Fainelli.
14) Memory leak in gmac_setup_txqs(), from Navid Emamdoost.
15) Fix double free in dpaa2-ptp code, from Ioana Ciornei.
16) Reject invalid MTU values in stmmac, from Jose Abreu.
17) Fix refcount leak in error path of u32 classifier, from Davide
Caratti.
18) Fix regression causing iwlwifi firmware crashes on boot, from Anders
Kaseorg.
19) Fix inverted return value logic in llc2 code, from Chan Shu Tak.
20) Disable hardware GRO when XDP is attached to qede, frm Manish
Chopra.
21) Since we encode state in the low pointer bits, dst metrics must be
at least 4 byte aligned, which is not necessarily true on m68k. Add
annotations to fix this, from Geert Uytterhoeven.
* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (160 commits)
sfc: Include XDP packet headroom in buffer step size.
sfc: fix channel allocation with brute force
net: dst: Force 4-byte alignment of dst_metrics
selftests: pmtu: fix init mtu value in description
hv_netvsc: Fix unwanted rx_table reset
net: phy: ensure that phy IDs are correctly typed
mod_devicetable: fix PHY module format
qede: Disable hardware gro when xdp prog is installed
net: ena: fix issues in setting interrupt moderation params in ethtool
net: ena: fix default tx interrupt moderation interval
net/smc: unregister ib devices in reboot_event
net: stmmac: platform: Fix MDIO init for platforms without PHY
llc2: Fix return statement of llc_stat_ev_rx_null_dsap_xid_c (and _test_c)
net: hisilicon: Fix a BUG trigered by wrong bytes_compl
net: dsa: ksz: use common define for tag len
s390/qeth: don't return -ENOTSUPP to userspace
s390/qeth: fix promiscuous mode after reset
s390/qeth: handle error due to unsupported transport mode
cxgb4: fix refcount init for TC-MQPRIO offload
tc-testing: initial tdc selftests for cls_u32
...
The sifive_l2_cache.c is in no way related to RISC-V architecture
memory management. It is a little stub driver working around the fact
that the EDAC maintainers prefer their drivers to be structured in a
certain way that doesn't fit the SiFive SOCs.
Move the file to drivers/soc and add a Kconfig option for it, as well
as the whole drivers/soc boilerplate for CONFIG_SOC_SIFIVE.
Fixes: a967a289f169 ("RISC-V: sifive_l2_cache: Add L2 cache controller driver for SiFive SoCs")
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Borislav Petkov <bp@suse.de>
[paul.walmsley@sifive.com: keep the MAINTAINERS change specific to the L2$ controller code]
Signed-off-by: Paul Walmsley <paul.walmsley@sifive.com>
Radim's kernel.org email is bouncing, which I take as a signal that
he is not really able to deal with KVM at this time. Make MAINTAINERS
match the effective value of KVM's bus factor.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>