Jan Kiszka reported that the x2apic_wrmsr_fence() function uses a plain
MFENCE while the Intel SDM (10.12.3 MSR Access in x2APIC Mode) calls for
MFENCE; LFENCE.
Short summary: we have special MSRs that have weaker ordering than all
the rest. Add fencing consistent with current SDM recommendations.
This is not known to cause any issues in practice, only in theory.
Longer story below:
The reason the kernel uses a different semantic is that the SDM changed
(roughly in late 2017). The SDM changed because folks at Intel were
auditing all of the recommended fences in the SDM and realized that the
x2apic fences were insufficient.
Why was the pain MFENCE judged insufficient?
WRMSR itself is normally a serializing instruction. No fences are needed
because the instruction itself serializes everything.
But, there are explicit exceptions for this serializing behavior written
into the WRMSR instruction documentation for two classes of MSRs:
IA32_TSC_DEADLINE and the X2APIC MSRs.
Back to x2apic: WRMSR is *not* serializing in this specific case.
But why is MFENCE insufficient? MFENCE makes writes visible, but
only affects load/store instructions. WRMSR is unfortunately not a
load/store instruction and is unaffected by MFENCE. This means that a
non-serializing WRMSR could be reordered by the CPU to execute before
the writes made visible by the MFENCE have even occurred in the first
place.
This means that an x2apic IPI could theoretically be triggered before
there is any (visible) data to process.
Does this affect anything in practice? I honestly don't know. It seems
quite possible that by the time an interrupt gets to consume the (not
yet) MFENCE'd data, it has become visible, mostly by accident.
To be safe, add the SDM-recommended fences for all x2apic WRMSRs.
This also leaves open the question of the _other_ weakly-ordered WRMSR:
MSR_IA32_TSC_DEADLINE. While it has the same ordering architecture as
the x2APIC MSRs, it seems substantially less likely to be a problem in
practice. While writes to the in-memory Local Vector Table (LVT) might
theoretically be reordered with respect to a weakly-ordered WRMSR like
TSC_DEADLINE, the SDM has this to say:
In x2APIC mode, the WRMSR instruction is used to write to the LVT
entry. The processor ensures the ordering of this write and any
subsequent WRMSR to the deadline; no fencing is required.
But, that might still leave xAPIC exposed. The safest thing to do for
now is to add the extra, recommended LFENCE.
[ bp: Massage commit message, fix typos, drop accidentally added
newline to tools/arch/x86/include/asm/barrier.h. ]
Reported-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: <stable@vger.kernel.org>
Link: https://lkml.kernel.org/r/20200305174708.F77040DD@viggo.jf.intel.com
apic::irq_dest_mode is actually a boolean, but defined as u32 and named in
a way which does not explain what it means.
Make it a boolean and rename it to 'dest_mode_logical'
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20201024213535.443185-9-dwmw2@infradead.org
struct apic has two members which store information about the destination
mode: dest_logical and irq_dest_mode.
dest_logical contains a mask which was historically used to set the
destination mode in IPI messages. Over time the usage was reduced and the
logical/physical functions were seperated.
There are only a few places which still use 'dest_logical' but they can
use 'irq_dest_mode' instead.
irq_dest_mode is actually a boolean where 0 means physical destination mode
and 1 means logical destination mode. Of course the name does not reflect
the functionality. This will be cleaned up in a subsequent change.
Remove apic::dest_logical and fixup the remaining users.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20201024213535.443185-8-dwmw2@infradead.org
The enum ioapic_irq_destination_types and the enumerated constants starting
with 'dest_' are gross misnomers because they describe the delivery mode.
Rename then enum and the constants so they actually make sense.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20201024213535.443185-6-dwmw2@infradead.org
Currently, Linux as a hypervisor guest will enable x2apic only if there are
no CPUs present at boot time with an APIC ID above 255.
Hotplugging a CPU later with a higher APIC ID would result in a CPU which
cannot be targeted by external interrupts.
Add a filter in x2apic_apic_id_valid() which can be used to prevent such
CPUs from coming online, and allow x2apic to be enabled even if they are
present at boot time.
Fixes: ce69a78450 ("x86/apic: Enable x2APIC without interrupt remapping under KVM")
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20201024213535.443185-2-dwmw2@infradead.org
All callers of apic->send_IPI_all() and apic->send_IPI_allbutself() contain
the decision logic for shorthand invocation already and invoke
send_IPI_mask() if the prereqisites are not satisfied.
Implement shorthand support for x2apic.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20190722105221.134696837@linutronix.de
Now there are three small local headers. Some contain functions which are
only used in one source file.
Move all the inlines and declarations into a single local header and the
inlines which are only used in one source file into that.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20190722105219.618612624@linutronix.de
All of these APIC files include the world and some more. Remove the
unneeded cruft.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20190722105219.342631201@linutronix.de
The APIC ID as parsed from ACPI MADT is validity checked with the
apic->apic_id_valid() callback, which depends on the selected APIC type.
For non X2APIC types APIC IDs >= 0xFF are invalid, but values > 0x7FFFFFFF
are detected as valid. This happens because the 'apicid' argument of the
apic_id_valid() callback is type 'int'. So the resulting comparison
apicid < 0xFF
evaluates to true for all unsigned int values > 0x7FFFFFFF which are handed
to default_apic_id_valid(). As a consequence, invalid APIC IDs in !X2APIC
mode are considered valid and accounted as possible CPUs.
Change the apicid argument type of the apic_id_valid() callback to u32 so
the evaluation is unsigned and returns the correct result.
[ tglx: Massaged changelog ]
Signed-off-by: Li RongQing <lirongqing@baidu.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Cc: jgross@suse.com
Cc: Dou Liyang <douly.fnst@cn.fujitsu.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: hpa@zytor.com
Link: https://lkml.kernel.org/r/1523322966-10296-1-git-send-email-lirongqing@baidu.com
set_x2apic_phys_mode() is only called as part of early_param()
initialization - so mark it as __init.
Signed-off-by: Dou Liyang <douly.fnst@cn.fujitsu.com>
Cc: Juergen Gross <jgross@suse.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/20180117034543.26723-1-douly.fnst@cn.fujitsu.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.
By default all files without license information are under the default
license of the kernel, which is GPL version 2.
Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier. The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.
This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.
How this work was done:
Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
- file had no licensing information it it.
- file was a */uapi/* one with no licensing information in it,
- file was a */uapi/* one with existing licensing information,
Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.
The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne. Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.
The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed. Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.
Criteria used to select files for SPDX license identifier tagging was:
- Files considered eligible had to be source code files.
- Make and config files were included as candidates if they contained >5
lines of source
- File already had some variant of a license header in it (even if <5
lines).
All documentation files were explicitly excluded.
The following heuristics were used to determine which SPDX license
identifiers to apply.
- when both scanners couldn't find any license traces, file was
considered to have no license information in it, and the top level
COPYING file license applied.
For non */uapi/* files that summary was:
SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 11139
and resulted in the first patch in this series.
If that file was a */uapi/* path one, it was "GPL-2.0 WITH
Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was:
SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 WITH Linux-syscall-note 930
and resulted in the second patch in this series.
- if a file had some form of licensing information in it, and was one
of the */uapi/* ones, it was denoted with the Linux-syscall-note if
any GPL family license was found in the file or had no licensing in
it (per prior point). Results summary:
SPDX license identifier # files
---------------------------------------------------|------
GPL-2.0 WITH Linux-syscall-note 270
GPL-2.0+ WITH Linux-syscall-note 169
((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21
((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17
LGPL-2.1+ WITH Linux-syscall-note 15
GPL-1.0+ WITH Linux-syscall-note 14
((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5
LGPL-2.0+ WITH Linux-syscall-note 4
LGPL-2.1 WITH Linux-syscall-note 3
((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3
((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1
and that resulted in the third patch in this series.
- when the two scanners agreed on the detected license(s), that became
the concluded license(s).
- when there was disagreement between the two scanners (one detected a
license but the other didn't, or they both detected different
licenses) a manual inspection of the file occurred.
- In most cases a manual inspection of the information in the file
resulted in a clear resolution of the license that should apply (and
which scanner probably needed to revisit its heuristics).
- When it was not immediately clear, the license identifier was
confirmed with lawyers working with the Linux Foundation.
- If there was any question as to the appropriate license identifier,
the file was flagged for further research and to be revisited later
in time.
In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.
Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights. The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.
Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.
In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.
Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
- a full scancode scan run, collecting the matched texts, detected
license ids and scores
- reviewing anything where there was a license detected (about 500+
files) to ensure that the applied SPDX license was correct
- reviewing anything where there was no detection but the patch license
was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
SPDX license was correct
This produced a worksheet with 20 files needing minor correction. This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.
These .csv files were then reviewed by Greg. Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected. This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.) Finally Greg ran the script using the .csv files to
generate the patches.
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Now that the old allocator is gone, these apic functions are unused. Remove
them.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Juergen Gross <jgross@suse.com>
Tested-by: Yu Chen <yu.c.chen@intel.com>
Acked-by: Juergen Gross <jgross@suse.com>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Alok Kataria <akataria@vmware.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Rui Zhang <rui.zhang@intel.com>
Cc: "K. Y. Srinivasan" <kys@microsoft.com>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Len Brown <lenb@kernel.org>
Link: https://lkml.kernel.org/r/20170913213155.524662349@linutronix.de
As preparation for replacing the vector allocator, provide a new function
which takes a cpu number instead of a cpu mask to calculate/lookup the
resulting APIC destination id.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Juergen Gross <jgross@suse.com>
Tested-by: Yu Chen <yu.c.chen@intel.com>
Acked-by: Juergen Gross <jgross@suse.com>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Alok Kataria <akataria@vmware.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Rui Zhang <rui.zhang@intel.com>
Cc: "K. Y. Srinivasan" <kys@microsoft.com>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Len Brown <lenb@kernel.org>
The target_cpus() callback of the apic struct is not really useful. Some
APICs return cpu_online_mask and others cpus_all_mask. The latter is bogus
as it does not take holes in the cpus_possible_mask into account.
Replace it with cpus_online_mask which makes the most sense and remove the
callback.
The usage sites will be removed in a later step anyway, so get rid of it
now to have incremental changes.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Juergen Gross <jgross@suse.com>
Tested-by: Yu Chen <yu.c.chen@intel.com>
Acked-by: Juergen Gross <jgross@suse.com>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Alok Kataria <akataria@vmware.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Rui Zhang <rui.zhang@intel.com>
Cc: "K. Y. Srinivasan" <kys@microsoft.com>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Len Brown <lenb@kernel.org>
Link: https://lkml.kernel.org/r/20170913213154.070850916@linutronix.de
The set_apic_id() callback returns an unsigned long value which is handed
in to apic_write() as the value argument u32.
Adjust the return value so it returns u32 right away.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Juergen Gross <jgross@suse.com>
Tested-by: Yu Chen <yu.c.chen@intel.com>
Acked-by: Juergen Gross <jgross@suse.com>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Alok Kataria <akataria@vmware.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Rui Zhang <rui.zhang@intel.com>
Cc: "K. Y. Srinivasan" <kys@microsoft.com>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Len Brown <lenb@kernel.org>
Link: https://lkml.kernel.org/r/20170913213153.437208268@linutronix.de
These inline functions are used in both the cluster and the physical x2apic
code to fill in the function pointers of the apic structure. That means the
code is generated twice for no reason.
Move it to a C code and reuse it.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Juergen Gross <jgross@suse.com>
Tested-by: Yu Chen <yu.c.chen@intel.com>
Acked-by: Juergen Gross <jgross@suse.com>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Alok Kataria <akataria@vmware.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Rui Zhang <rui.zhang@intel.com>
Cc: "K. Y. Srinivasan" <kys@microsoft.com>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Len Brown <lenb@kernel.org>
Link: https://lkml.kernel.org/r/20170913213153.358954066@linutronix.de
All implementations of apic->cpu_mask_to_apicid_and() and the two incoming
cpumasks to search for the target.
Move that operation to the call site and rename it to cpu_mask_to_apicid()
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Keith Busch <keith.busch@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Christoph Hellwig <hch@lst.de>
Link: http://lkml.kernel.org/r/20170619235446.641575516@linutronix.de
Guided by grsecurity's analogous __read_only markings in arch/x86,
this applies several uses of __ro_after_init to structures that are
only updated during __init, and const for some structures that are
never updated. Additionally extends __init markings to some functions
that are only used during __init, and cleans up some missing C99 style
static initializers.
Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brad Spengler <spender@grsecurity.net>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: David Brown <david.brown@linaro.org>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Emese Revfy <re.emese@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mathias Krause <minipli@googlemail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: PaX Team <pageexec@freemail.hu>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: kernel-hardening@lists.openwall.com
Link: http://lkml.kernel.org/r/20160808232906.GA29731@www.outflux.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Both the per-APIC flag ".wait_for_init_deassert",
and the global atomic_t "init_deasserted"
are dead code -- remove them.
For all APIC types, "wait_for_master()"
prevents an AP from proceeding until the BSP has set
cpu_callout_mask, making "init_deasserted" {unnecessary}:
BSP: <de-assert INIT>
...
BSP: {set init_deasserted}
AP: wait_for_master()
set cpu_initialized_mask
wait for cpu_callout_mask
BSP: test cpu_initialized_mask
BSP: set cpu_callout_mask
AP: test cpu_callout_mask
AP: {wait for init_deasserted}
...
AP: <touch APIC>
Deleting the {dead code} above is necessary to enable
some parallelism in a future patch.
Signed-off-by: Len Brown <len.brown@intel.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Igor Mammedov <imammedo@redhat.com>
Cc: Jan H. Schönherr <jschoenh@amazon.de>
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: Zhu Guihua <zhugh.fnst@cn.fujitsu.com>
Link: http://lkml.kernel.org/r/de4b3a9bab894735e285870b5296da25ee6a8a5a.1439739165.git.len.brown@intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
If ACPI is disabled, acpi_gbl_FADT is not available, and and the build
breaks.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Link: http://lkml.kernel.org/r/55479708.2000104@siemens.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Since commit b5660ba76b ("x86, platforms: Remove NUMAQ") removed NUMAQ,
the mps_oem_check() apic callback has been obsolete. Remove it.
This allows generic_mps_oem_check() to be removed as well.
Signed-off-by: David Rientjes <rientjes@google.com>
Link: http://lkml.kernel.org/r/alpine.DEB.2.02.1407302349390.17503@chino.kir.corp.google.com
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
The trampoline_phys_{high,low} members of struct apic are always
initialized to DEFAULT_TRAMPOLINE_PHYS_HIGH and TRAMPOLINE_PHYS_LOW,
respectively. Hardwire the constants and remove the unneeded members.
Signed-off-by: David Rientjes <rientjes@google.com>
Link: http://lkml.kernel.org/r/alpine.DEB.2.02.1407302348330.17503@chino.kir.corp.google.com
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Now that there is only a single wait_for_init_deassert()
function, just convert the member of struct apic to a bool to
determine whether we need to wait for init_deassert to become
non-zero.
There are no more callers of default_wait_for_init_deassert(),
so fold it into the caller.
Signed-off-by: David Rientjes <rientjes@google.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/alpine.DEB.2.02.1402042354010.7839@chino.kir.corp.google.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
None of these files are actually using any __init type directives
and hence don't need to include <linux/init.h>. Most are just a
left over from __devinit and __cpuinit removal, or simply due to
code getting copied from one driver to the next.
[ hpa: undid incorrect removal from arch/x86/kernel/head_32.S ]
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Link: http://lkml.kernel.org/r/1389054026-12947-1-git-send-email-paul.gortmaker@windriver.com
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
When a HP ProLiant DL980 G7 Server boots a regular kernel,
there will be intermittent lost interrupts which could
result in a hang or (in extreme cases) data loss.
The reason is that this system only supports x2apic physical
mode, while the kernel boots with a logical-cluster default
setting.
This bug can be worked around by specifying the "x2apic_phys" or
"nox2apic" boot option, but we want to handle this system
without requiring manual workarounds.
The BIOS sets ACPI_FADT_APIC_PHYSICAL in FADT table.
As all apicids are smaller than 255, BIOS need to pass the
control to the OS with xapic mode, according to x2apic-spec,
chapter 2.9.
Current code handle x2apic when BIOS pass with xapic mode
enabled:
When user specifies x2apic_phys, or FADT indicates PHYSICAL:
1. During madt oem check, apic driver is set with xapic logical
or xapic phys driver at first.
2. enable_IR_x2apic() will enable x2apic_mode.
3. if user specifies x2apic_phys on the boot line, x2apic_phys_probe()
will install the correct x2apic phys driver and use x2apic phys mode.
Otherwise it will skip the driver will let x2apic_cluster_probe to
take over to install x2apic cluster driver (wrong one) even though FADT
indicates PHYSICAL, because x2apic_phys_probe does not check
FADT PHYSICAL.
Add checking x2apic_fadt_phys in x2apic_phys_probe() to fix the
problem.
Signed-off-by: Stoney Wang <song-bo.wang@hp.com>
[ updated the changelog and simplified the code ]
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Cc: stable@kernel.org
Link: http://lkml.kernel.org/r/1360263182-16226-1-git-send-email-yinghai@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Since there are only two locations where cpu_mask_to_apicid() is
called from, remove the operation and use only
cpu_mask_to_apicid_and() instead.
Signed-off-by: Alexander Gordeev <agordeev@redhat.com>
Suggested-and-acked-by: Suresh Siddha <suresh.b.siddha@intel.com>
Acked-by: Yinghai Lu <yinghai@kernel.org>
Link: http://lkml.kernel.org/r/20120614074935.GE3383@dhcp-26-207.brq.redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
If the HW implements round-robin interrupt delivery, this
enables multiple cpu's (which are part of the user specified
interrupt smp_affinity mask and belong to the same x2apic
cluster) to service the interrupt.
Also if the platform supports Power Aware Interrupt Routing,
then this enables the interrupt to be routed to an idle cpu or a
busy cpu depending on the perf/power bias tunable.
We are now grouping all the cpu's in a cluster to one vector
domain. So that will limit the total number of interrupt sources
handled by Linux. Previously we support "cpu-count *
available-vectors-per-cpu" interrupt sources but this will now
reduce to "cpu-count/16 * available-vectors-per-cpu".
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: yinghai@kernel.org
Cc: gorcunov@openvz.org
Cc: agordeev@redhat.com
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1337644682-19854-2-git-send-email-suresh.b.siddha@intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
We know both register and value for eoi beforehand,
so there's no need to check it and no need to do math
to calculate the msr. Saves instructions/branches
on each EOI when using x2apic.
I looked at the objdump output to verify that the
generated code looks right and actually is shorter.
The real improvemements will be on the KVM guest side
though, those come in a later patch.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Cc: Avi Kivity <avi@redhat.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: gleb@redhat.com
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/e019d1a125316f10d3e3a4b2f6bda41473f4fb72.1337184153.git.mst@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Add eoi_write callback so that kvm can override
eoi accesses without touching the rest of the apic.
As a side-effect, this will enable a micro-optimization
for apics using msr.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Cc: Avi Kivity <avi@redhat.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: gleb@redhat.com
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/0df425d746c49ac2ecc405174df87752869629d2.1337184153.git.mst@redhat.com
[ tidied it up a bit ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Provide systems that do not support x2apic cluster mode
a mechanism to select x2apic physical mode using the
FADT FORCE_APIC_PHYSICAL_DESTINATION_MODE bit.
Changes from v1: (based on Suresh's comments)
- removed #ifdef CONFIG_ACPI
- removed #include <linux/acpi.h>
Signed-off-by: Greg Pearson <greg.pearson@hp.com>
Acked-by: Suresh Siddha <suresh.b.siddha@intel.com>
Link: http://lkml.kernel.org/r/1335313436-32020-1-git-send-email-greg.pearson@hp.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
As suggested by Suresh Siddha and Yinghai Lu:
For x2apic pre-enabled systems, apic driver is set already early
through early_acpi_boot_init()/early_acpi_process_madt()/
acpi_parse_madt()/default_acpi_madt_oem_check() path so that
apic_id_valid() checking will be sufficient during MADT and SRAT
parsing.
For non-x2apic pre-enabled systems, all apic ids should be less
than 255.
This allows us to substitute the checks in
arch/x86/kernel/acpi/boot.c::acpi_parse_x2apic() and
arch/x86/mm/srat.c::acpi_numa_x2apic_affinity_init() with
apic->apic_id_valid().
In addition we can avoid feigning the x2apic cpu feature in the
NumaChip apic code.
The following apic drivers have separate apic_id_valid()
functions which will accept x2apic type IDs :
x2apic_phys
x2apic_cluster
x2apic_uv_x
apic_numachip
Signed-off-by: Steffen Persvold <sp@numascale.com>
Cc: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: Daniel J Blueman <daniel@numascale-asia.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Jack Steiner <steiner@sgi.com>
Link: http://lkml.kernel.org/r/1331925935-13372-1-git-send-email-sp@numascale.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Move APIC ID validity check into platform APIC code, so it can
be overridden when needed. For NumaChip systems, always trust
MADT, as it's constructed with high APIC IDs.
Behaviour verifies on standard x86 systems and on NumaChip
systems with this, and compile-tested with allyesconfig.
Signed-off-by: Daniel J Blueman <daniel@numascale-asia.com>
Reviewed-by: Steffen Persvold <sp@numascale.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: H. Peter Anvin <hpa@linux.intel.com>
Cc: Suresh Siddha <suresh.b.siddha@intel.com>
Link: http://lkml.kernel.org/r/1331709454-27966-1-git-send-email-daniel@numascale-asia.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This will pave the way for each apic driver to be self-contained
and eliminate the need for apic_probe[].
Order in which apic drivers are listed in the .apicdrivers
section is important, as this determines the apic probe order.
And this is enforced by the ordering of apic driver files in the
Makefile and the macros apic_driver()/apic_drivers().
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Tested-by: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: steiner@sgi.com
Cc: gorcunov@openvz.org
Cc: yinghai@kernel.org
Link: http://lkml.kernel.org/r/20110521005526.068775085@sbsiddha-MOBL3.sc.intel.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Use the unused probe routine in the apic driver to finalize the
apic model selection. This cleans up the
default_setup_apic_routing() and this probe routine in future
can also be used for doing any apic model specific
initialisation.
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Acked-by: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: steiner@sgi.com
Cc: yinghai@kernel.org
Link: http://lkml.kernel.org/r/20110519234637.247458931@sbsiddha-MOBL3.sc.intel.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>