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While the UDA1380 is described in some lpc3250 device trees, there is
currently no real user of that codec. Anyway, if the codec needs a clock,
it should take it explicitly.
lpc3250_machine_init is called for all the lpc32xx machines and some are
using test1_clk (for example to strobe an HW watchdog). Overwriting
TEST_CLK_SEL prevents booting those platforms.
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Tested-by: Gregory CLEMENT <gregory.clement@bootlin.com>
Signed-off-by: Vladimir Zapolskiy <vz@mleia.com>
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In case when the number of entries in the section header table is larger
then or equal to SHN_LORESERVE the size of the table is held in the sh_size
member of the initial entry in section header table instead of e_shnum.
Same with the string table index which is located in sh_link instead of
e_shstrndx.
This case is easily reproducible with KCFLAGS="-ffunction-sections",
bzImage build fails with "String table index out of bounds" error.
Signed-off-by: Artem Savkov <asavkov@redhat.com>
Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com>
Acked-by: Joe Lawrence <joe.lawrence@redhat.com>
Cc: Eric W . Biederman <ebiederm@xmission.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20181129155615.2594-1-asavkov@redhat.com
[ Simplify the die() lines. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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This localizes the <mach/irqs.h> header to the mach-ixp4xx
directory, removes NR_IRQS and switches IXP4xx over to using
SPARSE_IRQ.
This is a prerequisite for DT support.
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
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All IXP4xx devices except the beeper passes the IRQ as a
resource, augment the NSLU2 beeper to do the same.
This is a prerequisite for SPARSE_IRQ.
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
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This rewrites the IXP4xx to use MULTI_IRQ_HANDLER and
create an irqdomain for the irqchip in the platform. We
convert the timer to request the interrupt like any other
driver in the process.
We bump all IRQs to 16+offset to avoid using IRQ 0 and
set NR_IRQS to 512 (the default for most systems).
This conveniently fits with the first 16 IRQs being
pre-allocated when using SPARSE_IRQ.
This is a prerequisite for SPARSE_IRQ and DT boot.
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
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DEBUG_HOTPLUG_CPU0 debug feature offlines a CPU as early as possible
allowing userspace to boot up without that CPU (so that it is possible
to check for unwanted dependencies towards the offlined CPU). After
doing so it emits a "CPU %u is now offline" pr_info, which is not enough
descriptive of why the CPU was offlined (e.g., one might be running with
a config that triggered some problem, not being aware that CONFIG_DEBUG_
HOTPLUG_CPU0 is set).
Add a bit more of informative text to the pr_info, so that it is
immediately obvious why a CPU has been offlined in early boot stages.
Background:
Got to scratch my head a bit while debugging a WARNING splat related to
the offlining of CPU0. Without being aware yet of this debug option it
wasn't immediately obvious why CPU0 was being offlined by the kernel.
Signed-off-by: Juri Lelli <juri.lelli@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: fenghua.yu@intel.com
Link: http://lkml.kernel.org/r/20181219151647.15073-1-juri.lelli@redhat.com
[ Merge line-broken line. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Linus pointed out that deciphering the raw #PF error code and printing
a more human readable message are two different things, and also that
printing the negative cases is mostly just noise[1]. For example, the
USER bit doesn't mean the fault originated in user code and stating
that an oops wasn't due to a protection keys violation isn't interesting
since an oops on a keys violation is a one-in-a-million scenario.
Remove the per-bit decoding of the error code and instead print:
- the raw error code
- why the fault occurred
- the effective privilege level of the access
- the type of access
- whether the fault originated in user code or kernel code
This provides the user with the information needed to triage 99.9% of
oopses without polluting the log with useless information or conflating
the error_code with the CPL.
Sample output:
BUG: kernel NULL pointer dereference, address = 0000000000000008
#PF: supervisor-privileged instruction fetch from kernel code
#PF: error_code(0x0010) - not-present page
BUG: unable to handle page fault for address = ffffbeef00000000
#PF: supervisor-privileged instruction fetch from kernel code
#PF: error_code(0x0010) - not-present page
BUG: unable to handle page fault for address = ffffc90000230000
#PF: supervisor-privileged write access from kernel code
#PF: error_code(0x000b) - reserved bit violation
[1] https://lkml.kernel.org/r/CAHk-=whk_fsnxVMvF1T2fFCaP2WrvSybABrLQCWLJyCvHw6NKA@mail.gmail.com
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@surriel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Yu-cheng Yu <yu-cheng.yu@intel.com>
Link: http://lkml.kernel.org/r/20181221213657.27628-3-sean.j.christopherson@intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Reword the NULL pointer dereference case to simply state that a NULL
pointer was dereferenced, i.e. drop "unable to handle" as that implies
that there are instances where the kernel actual does handle NULL
pointer dereferences, which is not true barring funky exception fixup.
For the non-NULL case, replace "kernel paging request" with "page fault"
as the kernel can technically oops on faults that originated in user
code. Dropping "kernel" also allows future patches to provide detailed
information on where the fault occurred, e.g. user vs. kernel, without
conflicting with the initial BUG message.
In both cases, replace "at address=" with wording more appropriate to
the oops, as "at" may be interpreted as stating that the address is the
RIP of the instruction that faulted.
Last, and probably least, further qualify the NULL-pointer path by
checking that the fault actually originated in kernel code. It's
technically possible for userspace to map address 0, and not printing
a super specific message is the least of our worries if the kernel does
manage to oops on an actual NULL pointer dereference from userspace.
Before:
BUG: unable to handle kernel NULL pointer dereference at ffffbeef00000000
BUG: unable to handle kernel paging request at ffffbeef00000000
After:
BUG: kernel NULL pointer dereference, address = 0000000000000008
BUG: unable to handle page fault for address = ffffbeef00000000
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@surriel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Yu-cheng Yu <yu-cheng.yu@intel.com>
Link: http://lkml.kernel.org/r/20181221213657.27628-2-sean.j.christopherson@intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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For new Centaur CPUs the ucode will take care of the preservation of cache coherence
between CPU cores in C-states regardless of how deep the C-states are. So, it is not
necessary to flush the caches in software befor entering C3. This useless operation
will cause performance drop for the cores which share some caches with the idling core.
Signed-off-by: David Wang <davidwang@zhaoxin.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Pavel Machek <pavel@ucw.cz>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: brucechang@via-alliance.com
Cc: cooperyan@zhaoxin.com
Cc: len.brown@intel.com
Cc: linux-pm@kernel.org
Cc: qiyuanwang@zhaoxin.com
Cc: rjw@rjwysocki.net
Cc: timguo@zhaoxin.com
Link: http://lkml.kernel.org/r/1545900110-2757-1-git-send-email-davidwang@zhaoxin.com
[ Tidy up the comment. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Use DEFINE_DEBUGFS_ATTRIBUTE() rather than DEFINE_SIMPLE_ATTRIBUTE()
for debugfs files.
Semantic patch information:
Rationale: DEFINE_SIMPLE_ATTRIBUTE + debugfs_create_file()
imposes some significant overhead as compared to
DEFINE_DEBUGFS_ATTRIBUTE + debugfs_create_file_unsafe().
Generated by: scripts/coccinelle/api/debugfs/debugfs_simple_attr.cocci
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Vishal Verma <vishal.l.verma@intel.com>
Cc: Yazen Ghannam <yazen.ghannam@amd.com>
Cc: kernel-janitors@vger.kernel.org
Link: http://lkml.kernel.org/r/1545981853-70877-1-git-send-email-yuehaibing@huawei.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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priority
The "ENERGY_PERF_BIAS: Set to 'normal', was 'performance'" message triggers
on pretty much every Intel machine. The purpose of log messages with
a warning level is to notify the user of something which potentially is
a problem, or at least somewhat unexpected.
This message clearly does not match those criteria, so lower its log
priority from warning to info.
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20181230172715.17469-1-hdegoede@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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This per cpu variable is accessed from assembler code, so it needs
to be visible for LTO.
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: pbonzini@redhat.com
Link: https://lkml.kernel.org/r/20190330004743.29541-8-andi@firstfloor.org
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This function is referrenced from assembler, so it needs to be marked
visible for LTO.
Fixes: 3a025de64bf8 ("x86/hyperv: Enable PV qspinlock for Hyper-V")
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Yi Sun <yi.y.sun@linux.intel.com>
Cc: kys@microsoft.com
Cc: haiyangz@microsoft.com
Link: https://lkml.kernel.org/r/20190330004743.29541-6-andi@firstfloor.org
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LTO will happily inline __const_udelay() everywhere it is used. Forcing it
noinline saves ~44k text in a LTO build.
13999560 1740864 1499136 17239560 1070e08 vmlinux-with-udelay-inline
13954764 1736768 1499136 17190668 1064f0c vmlinux-wo-udelay-inline
Even without LTO this function should never be inlined.
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20190330004743.29541-4-andi@firstfloor.org
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The "vide" inline assembler is only needed on 32bit kernels for old
32bit only CPUs.
Guard it with an #ifdef so it's not included in 64bit builds.
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20190330004743.29541-2-andi@firstfloor.org
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With gcc toplevel assembler statements that do not mark themselves as .text
may end up in other sections. This causes LTO boot crashes because various
assembler statements ended up in the middle of the initcall section. It's
also a latent problem without LTO, although it's currently not known to
cause any real problems.
According to the gcc team it's expected behavior.
Always mark all the top level assembler statements as text so that they
switch to the right section.
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20190330004743.29541-1-andi@firstfloor.org
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Some of the recently added const tables use __initdata which causes section
attribute conflicts.
Use __initconst instead.
Fixes: fa1202ef2243 ("x86/speculation: Add command line control")
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20190330004743.29541-9-andi@firstfloor.org
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Avoid kretprobe recursion loop bg by setting a dummy
kprobes to current_kprobe per-CPU variable.
This bug has been introduced with the asm-coded trampoline
code, since previously it used another kprobe for hooking
the function return placeholder (which only has a nop) and
trampoline handler was called from that kprobe.
This revives the old lost kprobe again.
With this fix, we don't see deadlock anymore.
And you can see that all inner-called kretprobe are skipped.
event_1 235 0
event_2 19375 19612
The 1st column is recorded count and the 2nd is missed count.
Above shows (event_1 rec) + (event_2 rec) ~= (event_2 missed)
(some difference are here because the counter is racy)
Reported-by: Andrea Righi <righi.andrea@gmail.com>
Tested-by: Andrea Righi <righi.andrea@gmail.com>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Fixes: c9becf58d935 ("[PATCH] kretprobe: kretprobe-booster")
Link: http://lkml.kernel.org/r/155094064889.6137.972160690963039.stgit@devbox
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Verify the stack frame pointer on kretprobe trampoline handler,
If the stack frame pointer does not match, it skips the wrong
entry and tries to find correct one.
This can happen if user puts the kretprobe on the function
which can be used in the path of ftrace user-function call.
Such functions should not be probed, so this adds a warning
message that reports which function should be blacklisted.
Tested-by: Andrea Righi <righi.andrea@gmail.com>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/155094059185.6137.15527904013362842072.stgit@devbox
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Make the anon_inodes facility unconditional so that it can be used by core
VFS code and pidfd code.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
[christian@brauner.io: adapt commit message to mention pidfds]
Signed-off-by: Christian Brauner <christian@brauner.io>
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The "event counter" was removed from rseq before it was merged upstream.
However, a few comments in the source code still refer to it. Adapt the
comments to match reality.
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Ben Maurer <bmaurer@fb.com>
Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Chris Lameter <cl@linux.com>
Cc: Dave Watson <davejwatson@fb.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Joel Fernandes <joelaf@google.com>
Cc: Josh Triplett <josh@joshtriplett.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Paul Turner <pjt@google.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Cc: linux-api@vger.kernel.org
Link: http://lkml.kernel.org/r/20190305194755.2602-2-mathieu.desnoyers@efficios.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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On x86 systems, only MSDOS and GPT partition tables are typically
encountered. Remove all the rest.
Note, CONFIG_EFI_PARTITION is also removed since it defaults to `y'.
Signed-off-by: Ahmed S. Darwish <darwish.07@gmail.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20190306004425.GA30537@darwi-home-pc
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Syntax only, no functional or semantic change.
This routine matches packages, not die, so name it thus.
Signed-off-by: Len Brown <len.brown@intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Link: http://lkml.kernel.org/r/7ca18c4ae7816a1f9eda37414725df676e63589d.1551160674.git.len.brown@intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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blsp1_i2c1 is at 0x0c175000
blsp2_i2c5 is at 0x0c1ba000 (the label is correct)
Fixes: 1e71d0c273d0a ("arm64: dts: qcom: msm8998: Enumerate i2c controllers")
Signed-off-by: Marc Gonzalez <marc.w.gonzalez@free.fr>
Reviewed-by: Jeffrey Hugo <jhugo@codeaurora.org>
Signed-off-by: Andy Gross <agross@kernel.org>
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The compatible flag should be different for each board to match
with the dtb and to let the bootloader pick the appropriate dtb.
Signed-off-by: Khasim Syed Mohammed <khasim.mohammed@linaro.org>
Signed-off-by: Niklas Cassel <niklas.cassel@linaro.org>
Signed-off-by: Andy Gross <agross@kernel.org>
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This adds the gpio-ranges property so that the GPIO pins are initialized
by the GPIO framework and not pinctrl. This fixes a circular dependency
between these two frameworks so GPIO hogging can be used on this board.
This was not tested on this particular hardware, however this same
change was tested on qcom-pm8941 using a LG Nexus 5 (hammerhead) phone.
Signed-off-by: Brian Masney <masneyb@onstation.org>
Signed-off-by: Andy Gross <agross@kernel.org>
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This adds the gpio-ranges property so that the GPIO pins are initialized
by the GPIO framework and not pinctrl. This fixes a circular dependency
between these two frameworks so GPIO hogging can be used on this board.
This was not tested on this particular hardware, however this same
change was tested on qcom-pm8941 using a LG Nexus 5 (hammerhead) phone.
Signed-off-by: Brian Masney <masneyb@onstation.org>
Signed-off-by: Andy Gross <agross@kernel.org>
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This adds the gpio-ranges property so that the GPIO pins are initialized
by the GPIO framework and not pinctrl. This fixes a circular dependency
between these two frameworks so GPIO hogging can be used on this board.
This was not tested on this particular hardware, however this same
change was tested on qcom-pm8941 using a LG Nexus 5 (hammerhead) phone.
Signed-off-by: Brian Masney <masneyb@onstation.org>
Signed-off-by: Andy Gross <agross@kernel.org>
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This adds the gpio-ranges property so that the GPIO pins are initialized
by the GPIO framework and not pinctrl. This fixes a circular dependency
between these two frameworks so GPIO hogging can be used on this board.
This was not tested on this particular hardware, however this same
change was tested on qcom-pm8941 using a LG Nexus 5 (hammerhead) phone.
Signed-off-by: Brian Masney <masneyb@onstation.org>
Signed-off-by: Andy Gross <agross@kernel.org>
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The XO-1 and XO-1.5 batteries apparently differ in an ability to report
ambient temperature. We need to use a different compatible string for the
XO-1.5 battery.
Previously olpc_dt_fixup() used the presence of the battery node's
compatible property to decide whether the DT is up to date. Now we need
to look for a particular value in the compatible string, to decide
Signed-off-by: Lubomir Rintel <lkundrak@v3.sk>
Acked-by: Pavel Machek <pavel@ucw.cz>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>
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This makes the following patch more concise.
Signed-off-by: Lubomir Rintel <lkundrak@v3.sk>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>
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It was pointed out in a review, and checkpatch.pl complains about this.
Breaking it down into multiple ofw evaluations works just as well and
reads better.
Signed-off-by: Lubomir Rintel <lkundrak@v3.sk>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>
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git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux
Pull arm64 fix from Catalin Marinas:
"Avoid compiler uninitialised warning introduced by recent arm64 futex
fix"
* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
arm64: futex: Restore oldval initialization to work around buggy compilers
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Commit 045afc24124d ("arm64: futex: Fix FUTEX_WAKE_OP atomic ops with
non-zero result value") removed oldval's zero initialization in
arch_futex_atomic_op_inuser because it is not necessary. Unfortunately,
Android's arm64 GCC 4.9.4 [1] does not agree:
../kernel/futex.c: In function 'do_futex':
../kernel/futex.c:1658:17: warning: 'oldval' may be used uninitialized
in this function [-Wmaybe-uninitialized]
return oldval == cmparg;
^
In file included from ../kernel/futex.c:73:0:
../arch/arm64/include/asm/futex.h:53:6: note: 'oldval' was declared here
int oldval, ret, tmp;
^
GCC fails to follow that when ret is non-zero, futex_atomic_op_inuser
returns right away, avoiding the uninitialized use that it claims.
Restoring the zero initialization works around this issue.
[1]: https://android.googlesource.com/platform/prebuilts/gcc/linux-x86/aarch64/aarch64-linux-android-4.9/
Cc: stable@vger.kernel.org
Fixes: 045afc24124d ("arm64: futex: Fix FUTEX_WAKE_OP atomic ops with non-zero result value")
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
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To minimize the latency of timer interrupts as observed by the guest,
KVM adjusts the values it programs into the host timers to account for
the host's overhead of programming and handling the timer event. In
the event that the adjustments are too aggressive, i.e. the timer fires
earlier than the guest expects, KVM busy waits immediately prior to
entering the guest.
Currently, KVM manually converts the delay from nanoseconds to clock
cycles. But, the conversion is done in the guest's time domain, while
the delay occurs in the host's time domain. This is perfectly ok when
the guest and host are using the same TSC ratio, but if the guest is
using a different ratio then the delay may not be accurate and could
wait too little or too long.
When the guest is not using the host's ratio, convert the delay from
guest clock cycles to host nanoseconds and use ndelay() instead of
__delay() to provide more accurate timing. Because converting to
nanoseconds is relatively expensive, e.g. requires division and more
multiplication ops, continue using __delay() directly when guest and
host TSCs are running at the same ratio.
Cc: Liran Alon <liran.alon@oracle.com>
Cc: Wanpeng Li <wanpengli@tencent.com>
Cc: stable@vger.kernel.org
Fixes: 3b8a5df6c4dc6 ("KVM: LAPIC: Tune lapic_timer_advance_ns automatically")
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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The introduction of adaptive tuning of lapic timer advancement did not
allow for the scenario where userspace would want to disable adaptive
tuning but still employ timer advancement, e.g. for testing purposes or
to handle a use case where adaptive tuning is unable to settle on a
suitable time. This is epecially pertinent now that KVM places a hard
threshold on the maximum advancment time.
Rework the timer semantics to accept signed values, with a value of '-1'
being interpreted as "use adaptive tuning with KVM's internal default",
and any other value being used as an explicit advancement time, e.g. a
time of '0' effectively disables advancement.
Note, this does not completely restore the original behavior of
lapic_timer_advance_ns. Prior to tracking the advancement per vCPU,
which is necessary to support autotuning, userspace could adjust
lapic_timer_advance_ns for *running* vCPU. With per-vCPU tracking, the
module params are snapshotted at vCPU creation, i.e. applying a new
advancement effectively requires restarting a VM.
Dynamically updating a running vCPU is possible, e.g. a helper could be
added to retrieve the desired delay, choosing between the global module
param and the per-VCPU value depending on whether or not auto-tuning is
(globally) enabled, but introduces a great deal of complexity. The
wrapper itself is not complex, but understanding and documenting the
effects of dynamically toggling auto-tuning and/or adjusting the timer
advancement is nigh impossible since the behavior would be dependent on
KVM's implementation as well as compiler optimizations. In other words,
providing stable behavior would require extremely careful consideration
now and in the future.
Given that the expected use of a manually-tuned timer advancement is to
"tune once, run many", use the vastly simpler approach of recognizing
changes to the module params only when creating a new vCPU.
Cc: Liran Alon <liran.alon@oracle.com>
Cc: Wanpeng Li <wanpengli@tencent.com>
Reviewed-by: Liran Alon <liran.alon@oracle.com>
Cc: stable@vger.kernel.org
Fixes: 3b8a5df6c4dc6 ("KVM: LAPIC: Tune lapic_timer_advance_ns automatically")
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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Automatically adjusting the globally-shared timer advancement could
corrupt the timer, e.g. if multiple vCPUs are concurrently adjusting
the advancement value. That could be partially fixed by using a local
variable for the arithmetic, but it would still be susceptible to a
race when setting timer_advance_adjust_done.
And because virtual_tsc_khz and tsc_scaling_ratio are per-vCPU, the
correct calibration for a given vCPU may not apply to all vCPUs.
Furthermore, lapic_timer_advance_ns is marked __read_mostly, which is
effectively violated when finding a stable advancement takes an extended
amount of timer.
Opportunistically change the definition of lapic_timer_advance_ns to
a u32 so that it matches the style of struct kvm_timer. Explicitly
pass the param to kvm_create_lapic() so that it doesn't have to be
exposed to lapic.c, thus reducing the probability of unintentionally
using the global value instead of the per-vCPU value.
Cc: Liran Alon <liran.alon@oracle.com>
Cc: Wanpeng Li <wanpengli@tencent.com>
Reviewed-by: Liran Alon <liran.alon@oracle.com>
Cc: stable@vger.kernel.org
Fixes: 3b8a5df6c4dc6 ("KVM: LAPIC: Tune lapic_timer_advance_ns automatically")
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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To minimize the latency of timer interrupts as observed by the guest,
KVM adjusts the values it programs into the host timers to account for
the host's overhead of programming and handling the timer event. Now
that the timer advancement is automatically tuned during runtime, it's
effectively unbounded by default, e.g. if KVM is running as L1 the
advancement can measure in hundreds of milliseconds.
Disable timer advancement if adaptive tuning yields an advancement of
more than 5000ns, as large advancements can break reasonable assumptions
of the guest, e.g. that a timer configured to fire after 1ms won't
arrive on the next instruction. Although KVM busy waits to mitigate the
case of a timer event arriving too early, complications can arise when
shifting the interrupt too far, e.g. kvm-unit-test's vmx.interrupt test
will fail when its "host" exits on interrupts as KVM may inject the INTR
before the guest executes STI+HLT. Arguably the unit test is "broken"
in the sense that delaying a timer interrupt by 1ms doesn't technically
guarantee the interrupt will arrive after STI+HLT, but it's a reasonable
assumption that KVM should support.
Furthermore, an unbounded advancement also effectively unbounds the time
spent busy waiting, e.g. if the guest programs a timer with a very large
delay.
5000ns is a somewhat arbitrary threshold. When running on bare metal,
which is the intended use case, timer advancement is expected to be in
the general vicinity of 1000ns. 5000ns is high enough that false
positives are unlikely, while not being so high as to negatively affect
the host's performance/stability.
Note, a future patch will enable userspace to disable KVM's adaptive
tuning, which will allow priveleged userspace will to specifying an
advancement value in excess of this arbitrary threshold in order to
satisfy an abnormal use case.
Cc: Liran Alon <liran.alon@oracle.com>
Cc: Wanpeng Li <wanpengli@tencent.com>
Cc: stable@vger.kernel.org
Fixes: 3b8a5df6c4dc6 ("KVM: LAPIC: Tune lapic_timer_advance_ns automatically")
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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It was reported that with some special Multi Processor Group configuration,
e.g:
bcdedit.exe /set groupsize 1
bcdedit.exe /set maxgroup on
bcdedit.exe /set groupaware on
for a 16-vCPU guest WS2012 shows BSOD on boot when PV TLB flush mechanism
is in use.
Tracing kvm_hv_flush_tlb immediately reveals the issue:
kvm_hv_flush_tlb: processor_mask 0x0 address_space 0x0 flags 0x2
The only flag set in this request is HV_FLUSH_ALL_VIRTUAL_ADDRESS_SPACES,
however, processor_mask is 0x0 and no HV_FLUSH_ALL_PROCESSORS is specified.
We don't flush anything and apparently it's not what Windows expects.
TLFS doesn't say anything about such requests and newer Windows versions
seem to be unaffected. This all feels like a WS2012 bug, which is, however,
easy to workaround in KVM: let's flush everything when we see an empty
flush request, over-flushing doesn't hurt.
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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If guest sets MSR_IA32_TSCDEADLINE to value such that in host
time-domain it's shorter than lapic_timer_advance_ns, we can
reach a case that we call hrtimer_start() with expiration time set at
the past.
Because lapic_timer.timer is init with HRTIMER_MODE_ABS_PINNED, it
is not allowed to run in softirq and therefore will never expire.
To avoid such a scenario, verify that deadline expiration time is set on
host time-domain further than (now + lapic_timer_advance_ns).
A future patch can also consider adding a min_timer_deadline_ns module parameter,
similar to min_timer_period_us to avoid races that amount of ns it takes
to run logic could still call hrtimer_start() with expiration timer set
at the past.
Reviewed-by: Joao Martins <joao.m.martins@oracle.com>
Signed-off-by: Liran Alon <liran.alon@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc into HEAD
KVM/PPC fixes for 5.1
- Fix host hang in the HTM assist code for POWER9
- Take srcu read lock around memslot lookup
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Currently, the internal vcpu finalization functions use a different
name ("what") for the feature parameter than the name ("feature")
used in the documentation.
To avoid future confusion, this patch converts everything to use
the name "feature" consistently.
No functional change.
Suggested-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Dave Martin <Dave.Martin@arm.com>
Reviewed-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
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Correct virtualization of SVE relies for correctness on code in
set_sve_vls() that verifies consistency between the set of vector
lengths requested by userspace and the set of vector lengths
available on the host.
However, the purpose of this code is not obvious, and not likely to
be apparent at all to people who do not have detailed knowledge of
the SVE system-level architecture.
This patch adds a suitable comment to explain what these checks are
for.
No functional change.
Suggested-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Dave Martin <Dave.Martin@arm.com>
Reviewed-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
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A complicated DIV_ROUND_UP() expression is currently written out
explicitly in multiple places in order to specify the size of the
bitmap exchanged with userspace to represent the value of the
KVM_REG_ARM64_SVE_VLS pseudo-register.
Userspace currently has no direct way to work this out either: for
documentation purposes, the size is just quoted as 8 u64s.
To make this more intuitive, this patch replaces these with a
single define, which is also exported to userspace as
KVM_ARM64_SVE_VLS_WORDS.
Since the number of words in a bitmap is just the index of the last
word used + 1, this patch expresses the bound that way instead.
This should make it clearer what is being expressed.
For userspace convenience, the minimum and maximum possible vector
lengths relevant to the KVM ABI are exposed to UAPI as
KVM_ARM64_SVE_VQ_MIN, KVM_ARM64_SVE_VQ_MAX. Since the only direct
use for these at present is manipulation of KVM_REG_ARM64_SVE_VLS,
no corresponding _VL_ macros are defined. They could be added
later if a need arises.
Since use of DIV_ROUND_UP() was the only reason for including
<linux/kernel.h> in guest.c, this patch also removes that #include.
Suggested-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Dave Martin <Dave.Martin@arm.com>
Reviewed-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
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sve_reg_to_region() currently passes the result of
vcpu_sve_state_size() to array_index_nospec(), effectively
leading to a divide / modulo operation.
Currently the code bails out and returns -EINVAL if
vcpu_sve_state_size() turns out to be zero, in order to avoid going
ahead and attempting to divide by zero. This is reasonable, but it
should only happen if the kernel contains some other bug that
allowed this code to be reached without the vcpu having been
properly initialised.
To make it clear that this is a defence against bugs rather than
something that the user should be able to trigger, this patch marks
the check with WARN_ON().
Suggested-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Dave Martin <Dave.Martin@arm.com>
Reviewed-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
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Currently, the way error codes are generated when processing the
SVE register access ioctls in a bit haphazard.
This patch refactors the code so that the behaviour is more
consistent: now, -EINVAL should be returned only for unrecognised
register IDs or when some other runtime error occurs. -ENOENT is
returned for register IDs that are recognised, but whose
corresponding register (or slice) does not exist for the vcpu.
To this end, in {get,set}_sve_reg() we now delegate the
vcpu_has_sve() check down into {get,set}_sve_vls() and
sve_reg_to_region(). The KVM_REG_ARM64_SVE_VLS special case is
picked off first, then sve_reg_to_region() plays the role of
exhaustively validating or rejecting the register ID and (where
accepted) computing the applicable register region as before.
sve_reg_to_region() is rearranged so that -ENOENT or -EPERM is not
returned prematurely, before checking whether reg->id is in a
recognised range.
-EPERM is now only returned when an attempt is made to access an
actually existing register slice on an unfinalized vcpu.
Fixes: e1c9c98345b3 ("KVM: arm64/sve: Add SVE support to register access ioctl interface")
Fixes: 9033bba4b535 ("KVM: arm64/sve: Add pseudo-register for the guest's vector lengths")
Suggested-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Dave Martin <Dave.Martin@arm.com>
Reviewed-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
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* Remove a few redundant blank lines that are stylistically
inconsistent with code already in guest.c and are just taking up
space.
* Delete a couple of pointless empty default cases from switch
statements whose behaviour is otherwise obvious anyway.
* Fix some typos and consolidate some redundantly duplicated
comments.
* Respell the slice index check in sve_reg_to_region() as "> 0"
to be more consistent with what is logically being checked here
(i.e., "is the slice index too large"), even though we don't try
to cope with multiple slices yet.
No functional change.
Suggested-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Dave Martin <Dave.Martin@arm.com>
Reviewed-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
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Currently, the SVE register ID macros are not all defined in the
same way, and advertise the fact that FFR maps onto the nonexistent
predicate register P16. This is really just for kernel
convenience, and may lead userspace into bad habits.
Instead, this patch masks the ID macro arguments so that
architecturally invalid register numbers will not be passed through
any more, and uses a literal KVM_REG_ARM64_SVE_FFR_BASE macro to
define KVM_REG_ARM64_SVE_FFR(), similarly to the way the _ZREG()
and _PREG() macros are defined.
Rather than plugging in magic numbers for the number of Z- and P-
registers and the maximum possible number of register slices, this
patch provides definitions for those too. Userspace is going to
need them in any case, and it makes sense for them to come from
<uapi/asm/kvm.h>.
sve_reg_to_region() uses convenience constants that are defined in
a different way, and also makes use of the fact that the FFR IDs
are really contiguous with the P15 IDs, so this patch retains the
existing convenience constants in guest.c, supplemented with a
couple of sanity checks to check for consistency with the UAPI
header.
Fixes: e1c9c98345b3 ("KVM: arm64/sve: Add SVE support to register access ioctl interface")
Suggested-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Dave Martin <Dave.Martin@arm.com>
Reviewed-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
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Because of the logic in kvm_arm_sys_reg_{get,set}_reg() and
sve_id_visibility(), we should never call
{get,set}_id_aa64zfr0_el1() for a vcpu where !vcpu_has_sve(vcpu).
To avoid the code giving the impression that it is valid for these
functions to be called in this situation, and to help the compiler
make the right optimisation decisions, this patch adds WARN_ON()
for these cases.
Given the way the logic is spread out, this seems preferable to
dropping the checks altogether.
Suggested-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Dave Martin <Dave.Martin@arm.com>
Reviewed-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
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The vcpu finalization stubs kvm_arm_vcpu_finalize() and
kvm_arm_vcpu_is_finalized() are currently #defines for ARM, which
limits the type-checking that the compiler can do at runtime.
The only reason for them to be #defines was to avoid reliance on
the definition of struct kvm_vcpu, which is not available here due
to circular #include problems. However, because these are stubs
containing no code, they don't need the definition of struct
kvm_vcpu after all; only a declaration is needed (which is
available already).
So in the interests of cleanliness, this patch converts them to
inline functions.
No functional change.
Suggested-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Dave Martin <Dave.Martin@arm.com>
Reviewed-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
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