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.
code
Clone this repository
https://tangled.org/tjh.dev/kernel
git@gordian.tjh.dev:tjh.dev/kernel
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Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull kvm fix from Paolo Bonzini:
"Fix for the SLS mitigation, which makes a 'SETcc/RET' pair grow
to 'SETcc/RET/INT3'.
This doesn't fit in 4 bytes any more, so the alignment has to
change to 8 for this case"
* tag 'for-linus-5.17' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
kvm/emulate: Fix SETcc emulation function offsets with SLS
Pull input fixes from Dmitry Torokhov:
"Two driver fixes:
- a fix for zinitix touchscreen to properly report contacts
- a fix for aiptek tablet driver to be more resilient to devices with
incorrect descriptors"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input:
Input: aiptek - properly check endpoint type
Input: zinitix - do not report shadow fingers
The commit in Fixes started adding INT3 after RETs as a mitigation
against straight-line speculation.
The fastop SETcc implementation in kvm's insn emulator uses macro magic
to generate all possible SETcc functions and to jump to them when
emulating the respective instruction.
However, it hardcodes the size and alignment of those functions to 4: a
three-byte SETcc insn and a single-byte RET. BUT, with SLS, there's an
INT3 that gets slapped after the RET, which brings the whole scheme out
of alignment:
15: 0f 90 c0 seto %al
18: c3 ret
19: cc int3
1a: 0f 1f 00 nopl (%rax)
1d: 0f 91 c0 setno %al
20: c3 ret
21: cc int3
22: 0f 1f 00 nopl (%rax)
25: 0f 92 c0 setb %al
28: c3 ret
29: cc int3
and this explodes like this:
int3: 0000 [#1] PREEMPT SMP PTI
CPU: 0 PID: 2435 Comm: qemu-system-x86 Not tainted 5.17.0-rc8-sls #1
Hardware name: Dell Inc. Precision WorkStation T3400 /0TP412, BIOS A14 04/30/2012
RIP: 0010:setc+0x5/0x8 [kvm]
Code: 00 00 0f 1f 00 0f b6 05 43 24 06 00 c3 cc 0f 1f 80 00 00 00 00 0f 90 c0 c3 cc 0f \
1f 00 0f 91 c0 c3 cc 0f 1f 00 0f 92 c0 c3 cc <0f> 1f 00 0f 93 c0 c3 cc 0f 1f 00 \
0f 94 c0 c3 cc 0f 1f 00 0f 95 c0
Call Trace:
<TASK>
? x86_emulate_insn [kvm]
? x86_emulate_instruction [kvm]
? vmx_handle_exit [kvm_intel]
? kvm_arch_vcpu_ioctl_run [kvm]
? kvm_vcpu_ioctl [kvm]
? __x64_sys_ioctl
? do_syscall_64
? entry_SYSCALL_64_after_hwframe
</TASK>
Raise the alignment value when SLS is enabled and use a macro for that
instead of hard-coding naked numbers.
Fixes: e463a09af2f0 ("x86: Add straight-line-speculation mitigation")
Reported-by: Jamie Heilman <jamie@audible.transient.net>
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Jamie Heilman <jamie@audible.transient.net>
Link: https://lore.kernel.org/r/YjGzJwjrvxg5YZ0Z@audible.transient.net
[Add a comment and a bit of safety checking, since this is going to be changed
again for IBT support. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Pull ARM SoC fix from Arnd Bergmann:
"Here is one last regression fix for 5.17, reverting a patch that went
into 5.16 as a cleanup that ended up breaking external interrupts on
Layerscape chips.
The revert makes it work again, but also reintroduces a build time
warning about the nonstandard DT binding that will have to be dealt
with in the future"
* tag 'soc-fixes-5.17-4' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc:
Revert "arm64: dts: freescale: Fix 'interrupt-map' parent address cells"
Syzbot reported warning in usb_submit_urb() which is caused by wrong
endpoint type. There was a check for the number of endpoints, but not
for the type of endpoint.
Fix it by replacing old desc.bNumEndpoints check with
usb_find_common_endpoints() helper for finding endpoints
Fail log:
usb 5-1: BOGUS urb xfer, pipe 1 != type 3
WARNING: CPU: 2 PID: 48 at drivers/usb/core/urb.c:502 usb_submit_urb+0xed2/0x18a0 drivers/usb/core/urb.c:502
Modules linked in:
CPU: 2 PID: 48 Comm: kworker/2:2 Not tainted 5.17.0-rc6-syzkaller-00226-g07ebd38a0da2 #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.14.0-2 04/01/2014
Workqueue: usb_hub_wq hub_event
...
Call Trace:
<TASK>
aiptek_open+0xd5/0x130 drivers/input/tablet/aiptek.c:830
input_open_device+0x1bb/0x320 drivers/input/input.c:629
kbd_connect+0xfe/0x160 drivers/tty/vt/keyboard.c:1593
Fixes: 8e20cf2bce12 ("Input: aiptek - fix crash on detecting device without endpoints")
Reported-and-tested-by: syzbot+75cccf2b7da87fb6f84b@syzkaller.appspotmail.com
Signed-off-by: Pavel Skripkin <paskripkin@gmail.com>
Link: https://lore.kernel.org/r/20220308194328.26220-1-paskripkin@gmail.com
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Pull arm64 fixes from Catalin Marinas:
"Fix two compiler warnings introduced by recent commits: pointer
arithmetic and double initialisation of struct field"
* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
arm64: errata: avoid duplicate field initializer
arm64: fix clang warning about TRAMP_VALIAS
Pull SCSI fixes from James Bottomley:
"Two small(ish) fixes, both in drivers"
* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
scsi: fnic: Finish scsi_cmnd before dropping the spinlock
scsi: mpt3sas: Page fault in reply q processing
This reverts commit 869f0ec048dc8fd88c0b2003373bd985795179fb. That
updated the expected device tree binding format for the ls-extirq
driver, without also updating the parsing code (ls_extirq_parse_map)
to the new format.
The context is that the ls-extirq driver uses the standard
"interrupt-map" OF property in a non-standard way, as suggested by
Rob Herring during review:
https://lore.kernel.org/lkml/20190927161118.GA19333@bogus/
This has turned out to be problematic, as Marc Zyngier discovered
through commit 041284181226 ("of/irq: Allow matching of an interrupt-map
local to an interrupt controller"), later fixed through commit
de4adddcbcc2 ("of/irq: Add a quirk for controllers with their own
definition of interrupt-map"). Marc's position, expressed on multiple
opportunities, is that:
(a) [ making private use of the reserved "interrupt-map" name in a
driver ] "is wrong, by the very letter of what an interrupt-map
means. If the interrupt map points to an interrupt controller,
that's the target for the interrupt."
https://lore.kernel.org/lkml/87k0g8jlmg.wl-maz@kernel.org/
(b) [ updating the driver's bindings to accept a non-reserved name for
this property, as an alternative, is ] "is totally pointless. These
machines have been in the wild for years, and existing DTs will be
there *forever*."
https://lore.kernel.org/lkml/87ilvrk1r0.wl-maz@kernel.org/
Considering the above, the Linux kernel has quirks in place to deal with
the ls-extirq's non-standard use of the "interrupt-map". These quirks
may be needed in other operating systems that consume this device tree,
yet this is seen as the only viable solution.
Therefore, the premise of the patch being reverted here is invalid.
It doesn't matter whether the driver, in its non-standard use of the
property, complies to the standard format or not, since this property
isn't expected to be used for interrupt translation by the core.
This change restores LS1088A, LS2088A/LS2085A and LX2160A to their
previous bindings, which allows these systems to continue to use
external interrupt lines with the correct polarity.
Fixes: 869f0ec048dc ("arm64: dts: freescale: Fix 'interrupt-map' parent address cells")
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Acked-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
I observed the following problem with the BT404 touch pad
running the Phosh UI:
When e.g. typing on the virtual keyboard pressing "g" would
produce "ggg".
After some analysis it turns out the firmware reports that three
fingers hit that coordinate at the same time, finger 0, 2 and
4 (of the five available 0,1,2,3,4).
DOWN
Zinitix-TS 3-0020: finger 0 down (246, 395)
Zinitix-TS 3-0020: finger 1 up (0, 0)
Zinitix-TS 3-0020: finger 2 down (246, 395)
Zinitix-TS 3-0020: finger 3 up (0, 0)
Zinitix-TS 3-0020: finger 4 down (246, 395)
UP
Zinitix-TS 3-0020: finger 0 up (246, 395)
Zinitix-TS 3-0020: finger 2 up (246, 395)
Zinitix-TS 3-0020: finger 4 up (246, 395)
This is one touch and release: i.e. this is all reported on
touch (down) and release.
There is a field in the struct touch_event called finger_cnt
which is actually a bitmask of the fingers active in the
event.
Rename this field finger_mask as this matches the use contents
better, then use for_each_set_bit() to iterate over just the
fingers that are actally active.
Factor out a finger reporting function zinitix_report_fingers()
to handle all fingers.
Also be more careful in reporting finger down/up: we were
reporting every event with input_mt_report_slot_state(..., true);
but this should only be reported on finger down or move,
not on finger up, so also add code to check p->sub_status
to see what is happening and report correctly.
After this my Zinitix BT404 touchscreen report fingers
flawlessly.
The vendor drive I have notably does not use the "finger_cnt"
and contains obviously incorrect code like this:
if (touch_dev->touch_info.finger_cnt > MAX_SUPPORTED_FINGER_NUM)
touch_dev->touch_info.finger_cnt = MAX_SUPPORTED_FINGER_NUM;
As MAX_SUPPORTED_FINGER_NUM is an ordinal and the field is
a bitmask this seems quite confused.
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20220228233017.2270599-1-linus.walleij@linaro.org
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Pull cifs fix from Steve French:
"Small fix for regression in multiuser mounts.
The additional improvements suggested by Ronnie to make the server and
session status handling code easier to read can wait for the 5.18
merge window."
* tag '5.17-rc8-smb3-fix' of git://git.samba.org/sfrench/cifs-2.6:
smb3: fix incorrect session setup check for multiuser mounts
The '.type' field is initialized both in place and in the macro
as reported by this W=1 warning:
arch/arm64/include/asm/cpufeature.h:281:9: error: initialized field overwritten [-Werror=override-init]
281 | (ARM64_CPUCAP_SCOPE_LOCAL_CPU | ARM64_CPUCAP_OPTIONAL_FOR_LATE_CPU)
| ^
arch/arm64/kernel/cpu_errata.c:136:17: note: in expansion of macro 'ARM64_CPUCAP_LOCAL_CPU_ERRATUM'
136 | .type = ARM64_CPUCAP_LOCAL_CPU_ERRATUM, \
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
arch/arm64/kernel/cpu_errata.c:145:9: note: in expansion of macro 'ERRATA_MIDR_RANGE'
145 | ERRATA_MIDR_RANGE(m, var, r_min, var, r_max)
| ^~~~~~~~~~~~~~~~~
arch/arm64/kernel/cpu_errata.c:613:17: note: in expansion of macro 'ERRATA_MIDR_REV_RANGE'
613 | ERRATA_MIDR_REV_RANGE(MIDR_CORTEX_A510, 0, 0, 2),
| ^~~~~~~~~~~~~~~~~~~~~
arch/arm64/include/asm/cpufeature.h:281:9: note: (near initialization for 'arm64_errata[18].type')
281 | (ARM64_CPUCAP_SCOPE_LOCAL_CPU | ARM64_CPUCAP_OPTIONAL_FOR_LATE_CPU)
| ^
Remove the extranous initializer.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Fixes: 1dd498e5e26a ("KVM: arm64: Workaround Cortex-A510's single-step and PAC trap errata")
Link: https://lore.kernel.org/r/20220316183800.1546731-1-arnd@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Pull perf tools fixes from Arnaldo Carvalho de Melo:
- Avoid iterating empty evlist, fixing a segfault with 'perf stat --null'
- Ignore case in topdown.slots check, fixing issue with Intel Icelake
JSON metrics.
- Fix symbol size calculation condition for fixing up corner case
symbol end address obtained from Kallsyms.
* tag 'perf-tools-fixes-for-v5.17-2022-03-19' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux:
perf parse-events: Ignore case in topdown.slots check
perf evlist: Avoid iteration for empty evlist.
perf symbols: Fix symbol size calculation condition
When aborting a SCSI command through fnic, there is a race with the fnic
interrupt handler which can result in the SCSI command and its request
being completed twice. If the interrupt handler claims the command by
setting CMD_SP to NULL first, the abort handler assumes the interrupt
handler has completed the command and returns SUCCESS, causing the request
for the scsi_cmnd to be re-queued.
But the interrupt handler may not have finished the command yet. After it
drops the spinlock protecting CMD_SP, it does memory cleanup before finally
calling scsi_done() to complete the scsi_cmnd. If the call to scsi_done
occurs after the abort handler finishes and re-queues the request, the
completion of the scsi_cmnd will advance and try to double complete a
request already queued for retry.
This patch fixes the issue by moving scsi_done() and any other use of
scsi_cmnd to before the spinlock is released by the interrupt handler.
Link: https://lore.kernel.org/r/20220311184359.2345319-1-djeffery@redhat.com
Reviewed-by: Laurence Oberman <loberman@redhat.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: David Jeffery <djeffery@redhat.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>