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14543 commits

Author SHA1 Message Date
Konrad Rzeszutek Wilk
c456442cd3 x86/bugs: Expose /sys/../spec_store_bypass
Add the sysfs file for the new vulerability. It does not do much except
show the words 'Vulnerable' for recent x86 cores.

Intel cores prior to family 6 are known not to be vulnerable, and so are
some Atoms and some Xeon Phi.

It assumes that older Cyrix, Centaur, etc. cores are immune.

Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Ingo Molnar <mingo@kernel.org>
2018-05-03 13:55:47 +02:00
Konrad Rzeszutek Wilk
5cf6875487 x86/bugs, KVM: Support the combination of guest and host IBRS
A guest may modify the SPEC_CTRL MSR from the value used by the
kernel. Since the kernel doesn't use IBRS, this means a value of zero is
what is needed in the host.

But the 336996-Speculative-Execution-Side-Channel-Mitigations.pdf refers to
the other bits as reserved so the kernel should respect the boot time
SPEC_CTRL value and use that.

This allows to deal with future extensions to the SPEC_CTRL interface if
any at all.

Note: This uses wrmsrl() instead of native_wrmsl(). I does not make any
difference as paravirt will over-write the callq *0xfff.. with the wrmsrl
assembler code.

Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Ingo Molnar <mingo@kernel.org>
2018-05-03 13:55:47 +02:00
Konrad Rzeszutek Wilk
1b86883ccb x86/bugs: Read SPEC_CTRL MSR during boot and re-use reserved bits
The 336996-Speculative-Execution-Side-Channel-Mitigations.pdf refers to all
the other bits as reserved. The Intel SDM glossary defines reserved as
implementation specific - aka unknown.

As such at bootup this must be taken it into account and proper masking for
the bits in use applied.

A copy of this document is available at
https://bugzilla.kernel.org/show_bug.cgi?id=199511

[ tglx: Made x86_spec_ctrl_base __ro_after_init ]

Suggested-by: Jon Masters <jcm@redhat.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Ingo Molnar <mingo@kernel.org>
2018-05-03 13:55:47 +02:00
Konrad Rzeszutek Wilk
d1059518b4 x86/bugs: Concentrate bug reporting into a separate function
Those SysFS functions have a similar preamble, as such make common
code to handle them.

Suggested-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Ingo Molnar <mingo@kernel.org>
2018-05-03 13:55:46 +02:00
Konrad Rzeszutek Wilk
4a28bfe326 x86/bugs: Concentrate bug detection into a separate function
Combine the various logic which goes through all those
x86_cpu_id matching structures in one function.

Suggested-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Ingo Molnar <mingo@kernel.org>
2018-05-03 13:55:46 +02:00
Thomas Gleixner
c65732e4f7 x86/cpu: Restore CPUID_8000_0008_EBX reload
The recent commt which addresses the x86_phys_bits corruption with
encrypted memory on CPUID reload after a microcode update lost the reload
of CPUID_8000_0008_EBX as well.

As a consequence IBRS and IBRS_FW are not longer detected

Restore the behaviour by bringing the reload of CPUID_8000_0008_EBX
back. This restore has a twist due to the convoluted way the cpuid analysis
works:

CPUID_8000_0008_EBX is used by AMD to enumerate IBRB, IBRS, STIBP. On Intel
EBX is not used. But the speculation control code sets the AMD bits when
running on Intel depending on the Intel specific speculation control
bits. This was done to use the same bits for alternatives.

The change which moved the 8000_0008 evaluation out of get_cpu_cap() broke
this nasty scheme due to ordering. So that on Intel the store to
CPUID_8000_0008_EBX clears the IBRB, IBRS, STIBP bits which had been set
before by software.

So the actual CPUID_8000_0008_EBX needs to go back to the place where it
was and the phys/virt address space calculation cannot touch it.

In hindsight this should have used completely synthetic bits for IBRB,
IBRS, STIBP instead of reusing the AMD bits, but that's for 4.18.

/me needs to find time to cleanup that steaming pile of ...

Fixes: d94a155c59 ("x86/cpu: Prevent cpuinfo_x86::x86_phys_bits adjustment corruption")
Reported-by: Jörg Otte <jrg.otte@gmail.com>
Reported-by: Tim Chen <tim.c.chen@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Jörg Otte <jrg.otte@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: kirill.shutemov@linux.intel.com
Cc: Borislav Petkov <bp@alien8.de
Link: https://lkml.kernel.org/r/alpine.DEB.2.21.1805021043510.1668@nanos.tec.linutronix.de
2018-05-02 16:44:38 +02:00
Thomas Gleixner
604a98f1df Merge branch 'timers/urgent' into timers/core
Pick up urgent fixes to apply dependent cleanup patch
2018-05-02 16:11:12 +02:00
Peter Zijlstra
e3b4f79025 x86/tsc: Fix mark_tsc_unstable()
mark_tsc_unstable() also needs to affect tsc_early, Now that
clocksource_mark_unstable() can be used on a clocksource irrespective of
its registration state, use it on both tsc_early and tsc.

This does however require cs->list to be initialized empty, otherwise it
cannot tell the registation state before registation.

Fixes: aa83c45762 ("x86/tsc: Introduce early tsc clocksource")
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Diego Viola <diego.viola@gmail.com>
Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: len.brown@intel.com
Cc: rjw@rjwysocki.net
Cc: rui.zhang@intel.com
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20180430100344.533326547@infradead.org
2018-05-02 16:10:40 +02:00
Peter Zijlstra
e9088adda1 x86/tsc: Always unregister clocksource_tsc_early
Don't leave the tsc-early clocksource registered if it errors out
early.

This was reported by Diego, who on his Core2 era machine got TSC
invalidated while it was running with tsc-early (due to C-states).
This results in keeping tsc-early with very bad effects.

Reported-and-Tested-by: Diego Viola <diego.viola@gmail.com>
Fixes: aa83c45762 ("x86/tsc: Introduce early tsc clocksource")
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: len.brown@intel.com
Cc: rjw@rjwysocki.net
Cc: diego.viola@gmail.com
Cc: rui.zhang@intel.com
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20180430100344.350507853@infradead.org
2018-05-02 16:10:40 +02:00
Petr Tesarik
3db3eb2852 x86/setup: Do not reserve a crash kernel region if booted on Xen PV
Xen PV domains cannot shut down and start a crash kernel. Instead,
the crashing kernel makes a SCHEDOP_shutdown hypercall with the
reason code SHUTDOWN_crash, cf. xen_crash_shutdown() machine op in
arch/x86/xen/enlighten_pv.c.

A crash kernel reservation is merely a waste of RAM in this case. It
may also confuse users of kexec_load(2) and/or kexec_file_load(2).
When flags include KEXEC_ON_CRASH or KEXEC_FILE_ON_CRASH,
respectively, these syscalls return success, which is technically
correct, but the crash kexec image will never be actually used.

Signed-off-by: Petr Tesarik <ptesarik@suse.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Juergen Gross <jgross@suse.com>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: Dou Liyang <douly.fnst@cn.fujitsu.com>
Cc: Mikulas Patocka <mpatocka@redhat.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: xen-devel@lists.xenproject.org
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Jean Delvare <jdelvare@suse.de>
Link: https://lkml.kernel.org/r/20180425120835.23cef60c@ezekiel.suse.cz
2018-04-27 17:06:28 +02:00
Rajneesh Bhardwaj
f79b1c573c x86/i8237: Register device based on FADT legacy boot flag
From Skylake onwards, the platform controller hub (Sunrisepoint PCH) does
not support legacy DMA operations to IO ports 81h-83h, 87h, 89h-8Bh, 8Fh.
Currently this driver registers as syscore ops and its resume function is
called on every resume from S3. On Skylake and Kabylake, this causes a
resume delay of around 100ms due to port IO operations, which is a problem.

This change allows to load the driver only when the platform bios
explicitly supports such devices or has a cut-off date earlier than 2017
due to the following reasons:

   - The platforms released before year 2017 have support for the 8237.
     (except Sunrisepoint PCH e.g. Skylake)

   - Some of the BIOS that were released for platforms (Skylake, Kabylake)
     during 2016-17 are buggy. These BIOS do not set/unset the
     ACPI_FADT_LEGACY_DEVICES field in FADT table properly based on the
     presence or absence of the DMA device.

Very recently, open source system firmware like coreboot started unsetting
ACPI_FADT_LEGACY_DEVICES field in FADT table if the 8237 DMA device is not
present on the PCH.

Please refer to chapter 21 of 6th Generation Intel® Core™ Processor
Platform Controller Hub Family: BIOS Specification.

Signed-off-by: Rajneesh Bhardwaj <rajneesh.bhardwaj@intel.com>
Signed-off-by: Anshuman Gupta <anshuman.gupta@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: rjw@rjwysocki.net
Cc: hpa@zytor.com
Cc: Alan Cox <alan@linux.intel.com>
Link: https://lkml.kernel.org/r/1522336015-22994-1-git-send-email-anshuman.gupta@intel.com
2018-04-27 16:44:29 +02:00
jacek.tomaka@poczta.fm
b837913fc2 x86/cpu/intel: Add missing TLB cpuid values
Make kernel print the correct number of TLB entries on Intel Xeon Phi 7210
(and others)

Before:
[ 0.320005] Last level dTLB entries: 4KB 0, 2MB 0, 4MB 0, 1GB 0
After:
[ 0.320005] Last level dTLB entries: 4KB 256, 2MB 128, 4MB 128, 1GB 16

The entries do exist in the official Intel SMD but the type column there is
incorrect (states "Cache" where it should read "TLB"), but the entries for
the values 0x6B, 0x6C and 0x6D are correctly described as 'Data TLB'.

Signed-off-by: Jacek Tomaka <jacek.tomaka@poczta.fm>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20180423161425.24366-1-jacekt@dugeo.com
2018-04-26 21:42:44 +02:00
Borislav Petkov
4dba072cd0 x86/dumpstack: Explain the reasoning for the prologue and buffer size
The whole reasoning behind the amount of opcode bytes dumped and prologue
length isn't very clear so write down some of the reasons for why it is
done the way it is.

Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Link: https://lkml.kernel.org/r/20180417161124.5294-10-bp@alien8.de
2018-04-26 16:15:28 +02:00
Borislav Petkov
602bd705da x86/dumpstack: Save first regs set for the executive summary
Save the regs set when __die() is onvoked for the first time and print it
in oops_end().

Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Link: https://lkml.kernel.org/r/20180417161124.5294-9-bp@alien8.de
2018-04-26 16:15:28 +02:00
Borislav Petkov
7cccf0725c x86/dumpstack: Add a show_ip() function
... which shows the Instruction Pointer along with the insn bytes around
it. Use it whenever rIP is printed. Drop the rIP < PAGE_OFFSET check since
probe_kernel_read() can handle any address properly.

Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Link: https://lkml.kernel.org/r/20180417161124.5294-8-bp@alien8.de
2018-04-26 16:15:27 +02:00
Borislav Petkov
e8b6f98451 x86/dumpstack: Add loglevel argument to show_opcodes()
Will be used in the next patch.

Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Link: https://lkml.kernel.org/r/20180417161124.5294-6-bp@alien8.de
2018-04-26 16:15:26 +02:00
Borislav Petkov
9e4a90fd34 x86/dumpstack: Improve opcodes dumping in the code section
The code used to iterate byte-by-byte over the bytes around RIP and that
is expensive: disabling pagefaults around it, copy_from_user, etc...

Make it read the whole buffer of OPCODE_BUFSIZE size in one go. Use a
statically allocated 64 bytes buffer so that concurrent show_opcodes()
do not interleave in the output even though in the majority of the cases
it's serialized via die_lock. Except the #PF path which doesn't...

Also, do the PAGE_OFFSET check outside of the function because latter
will be reused in other context.

Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Link: https://lkml.kernel.org/r/20180417161124.5294-5-bp@alien8.de
2018-04-26 16:15:26 +02:00
Borislav Petkov
f0a1d7c11c x86/dumpstack: Carve out code-dumping into a function
No functionality change, carve it out into a separate function for later
changes.

Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Link: https://lkml.kernel.org/r/20180417161124.5294-4-bp@alien8.de
2018-04-26 16:15:26 +02:00
Borislav Petkov
5df61707f0 x86/dumpstack: Unexport oops_begin()
The only user outside of arch/ is not a module since

  86cd47334b ("ACPI, APEI, GHES, Prevent GHES to be built as module")

No functional changes.

Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Link: https://lkml.kernel.org/r/20180417161124.5294-3-bp@alien8.de
2018-04-26 16:15:26 +02:00
Borislav Petkov
5d12f0424e x86/dumpstack: Remove code_bytes
This was added by

  86c4183742 ("[PATCH] i386: add option to show more code in oops reports")

long time ago but experience shows that 64 instruction bytes are plenty
when deciphering an oops. So get rid of it.

Removing it will simplify further enhancements to the opcodes dumping
machinery coming in the following patches.

Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Link: https://lkml.kernel.org/r/20180417161124.5294-2-bp@alien8.de
2018-04-26 16:15:25 +02:00
Yazen Ghannam
da6fa7ef67 x86/smpboot: Don't use mwait_play_dead() on AMD systems
Recent AMD systems support using MWAIT for C1 state. However, MWAIT will
not allow deeper cstates than C1 on current systems.

play_dead() expects to use the deepest state available.  The deepest state
available on AMD systems is reached through SystemIO or HALT. If MWAIT is
available, it is preferred over the other methods, so the CPU never reaches
the deepest possible state.

Don't try to use MWAIT to play_dead() on AMD systems. Instead, use CPUIDLE
to enter the deepest state advertised by firmware. If CPUIDLE is not
available then fallback to HALT.

Signed-off-by: Yazen Ghannam <yazen.ghannam@amd.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Borislav Petkov <bp@suse.de>
Cc: stable@vger.kernel.org
Cc: Yazen Ghannam <Yazen.Ghannam@amd.com>
Link: https://lkml.kernel.org/r/20180403140228.58540-1-Yazen.Ghannam@amd.com
2018-04-26 16:06:19 +02:00
Eric W. Biederman
db78e6a0a6 signal: Add TRAP_UNK si_code for undiagnosted trap exceptions
Both powerpc and alpha have cases where they wronly set si_code to 0
in combination with SIGTRAP and don't mean SI_USER.

About half the time this is because the architecture can not report
accurately what kind of trap exception triggered the trap exception.
The other half the time it looks like no one has bothered to
figure out an appropriate si_code.

For the cases where the architecture does not have enough information
or is too lazy to figure out exactly what kind of trap exception
it is define TRAP_UNK.

Cc: linux-api@vger.kernel.org
Cc: linux-arch@vger.kernel.org
Cc: linux-alpha@vger.kernel.org
Cc: linuxppc-dev@lists.ozlabs.org
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2018-04-25 10:40:56 -05:00
Eric W. Biederman
3eb0f5193b signal: Ensure every siginfo we send has all bits initialized
Call clear_siginfo to ensure every stack allocated siginfo is properly
initialized before being passed to the signal sending functions.

Note: It is not safe to depend on C initializers to initialize struct
siginfo on the stack because C is allowed to skip holes when
initializing a structure.

The initialization of struct siginfo in tracehook_report_syscall_exit
was moved from the helper user_single_step_siginfo into
tracehook_report_syscall_exit itself, to make it clear that the local
variable siginfo gets fully initialized.

In a few cases the scope of struct siginfo has been reduced to make it
clear that siginfo siginfo is not used on other paths in the function
in which it is declared.

Instances of using memset to initialize siginfo have been replaced
with calls clear_siginfo for clarity.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2018-04-25 10:40:51 -05:00
Borislav Petkov
09e182d17e x86/microcode: Do not exit early from __reload_late()
Vitezslav reported a case where the

  "Timeout during microcode update!"

panic would hit. After a deeper look, it turned out that his .config had
CONFIG_HOTPLUG_CPU disabled which practically made save_mc_for_early() a
no-op.

When that happened, the discovered microcode patch wasn't saved into the
cache and the late loading path wouldn't find any.

This, then, lead to early exit from __reload_late() and thus CPUs waiting
until the timeout is reached, leading to the panic.

In hindsight, that function should have been written so it does not return
before the post-synchronization. Oh well, I know better now...

Fixes: bb8c13d61a ("x86/microcode: Fix CPU synchronization routine")
Reported-by: Vitezslav Samel <vitezslav@samel.cz>
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Vitezslav Samel <vitezslav@samel.cz>
Tested-by: Ashok Raj <ashok.raj@intel.com>
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/20180418081140.GA2439@pc11.op.pod.cz
Link: https://lkml.kernel.org/r/20180421081930.15741-2-bp@alien8.de
2018-04-24 09:48:22 +02:00
Borislav Petkov
84749d8375 x86/microcode/intel: Save microcode patch unconditionally
save_mc_for_early() was a no-op on !CONFIG_HOTPLUG_CPU but the
generic_load_microcode() path saves the microcode patches it has found into
the cache of patches which is used for late loading too. Regardless of
whether CPU hotplug is used or not.

Make the saving unconditional so that late loading can find the proper
patch.

Reported-by: Vitezslav Samel <vitezslav@samel.cz>
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Vitezslav Samel <vitezslav@samel.cz>
Tested-by: Ashok Raj <ashok.raj@intel.com>
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/20180418081140.GA2439@pc11.op.pod.cz
Link: https://lkml.kernel.org/r/20180421081930.15741-1-bp@alien8.de
2018-04-24 09:48:22 +02:00
Thomas Gleixner
7010adcdd2 x86/jailhouse: Fix incorrect SPDX identifier
GPL2.0 is not a valid SPDX identiier. Replace it with GPL-2.0.

Fixes: 4a362601ba ("x86/jailhouse: Add infrastructure for running in non-root cell")
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Jan Kiszka <jan.kiszka@siemens.com>
Cc: Kate Stewart <kstewart@linuxfoundation.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Philippe Ombredanne <pombredanne@nexb.com>
Link: https://lkml.kernel.org/r/20180422220832.815346488@linutronix.de
2018-04-23 10:17:28 +02:00
Linus Torvalds
37a535edd7 Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fixes from Thomas Gleixner:
 "A small set of fixes for x86:

   - Prevent X2APIC ID 0xFFFFFFFF from being treated as valid, which
     causes the possible CPU count to be wrong.

   - Prevent 32bit truncation in calc_hpet_ref() which causes the TSC
     calibration to fail

   - Fix the page table setup for temporary text mappings in the resume
     code which causes resume failures

   - Make the page table dump code handle HIGHPTE correctly instead of
     oopsing

   - Support for topologies where NUMA nodes share an LLC to prevent a
     invalid topology warning and further malfunction on such systems.

   - Remove the now unused pci-nommu code

   - Remove stale function declarations"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/power/64: Fix page-table setup for temporary text mapping
  x86/mm: Prevent kernel Oops in PTDUMP code with HIGHPTE=y
  x86,sched: Allow topologies where NUMA nodes share an LLC
  x86/processor: Remove two unused function declarations
  x86/acpi: Prevent X2APIC id 0xffffffff from being accounted
  x86/tsc: Prevent 32bit truncation in calc_hpet_ref()
  x86: Remove pci-nommu.c
2018-04-22 11:40:52 -07:00
Dave Young
a841aa83df kexec_file: do not add extra alignment to efi memmap
Chun-Yi reported a kernel warning message below:

  WARNING: CPU: 0 PID: 0 at ../mm/early_ioremap.c:182 early_iounmap+0x4f/0x12c()
  early_iounmap(ffffffffff200180, 00000118) [0] size not consistent 00000120

The problem is x86 kexec_file_load adds extra alignment to the efi
memmap: in bzImage64_load():

        efi_map_sz = efi_get_runtime_map_size();
        efi_map_sz = ALIGN(efi_map_sz, 16);

And __efi_memmap_init maps with the size including the alignment bytes
but efi_memmap_unmap use nr_maps * desc_size which does not include the
extra bytes.

The alignment in kexec code is only needed for the kexec buffer internal
use Actually kexec should pass exact size of the efi memmap to 2nd
kernel.

Link: http://lkml.kernel.org/r/20180417083600.GA1972@dhcp-128-65.nay.redhat.com
Signed-off-by: Dave Young <dyoung@redhat.com>
Reported-by: joeyli <jlee@suse.com>
Tested-by: Randy Wright <rwright@hpe.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-20 17:18:36 -07:00
David Wang
60882cc159 x86/Centaur: Initialize supported CPU features properly
Centaur CPUs have some Intel compatible capabilities,including Permformance
Monitoring Counters and CPU virtualization capabilities. Initialize them in
the Centaur specific init code.

Signed-off-by: David Wang <davidwang@zhaoxin.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: lukelin@viacpu.com
Cc: qiyuanwang@zhaoxin.com
Cc: gregkh@linuxfoundation.org
Cc: brucechang@via-alliance.com
Cc: timguo@zhaoxin.com
Cc: cooperyan@zhaoxin.com
Cc: hpa@zytor.com
Cc: benjaminpan@viatech.com
Link: https://lkml.kernel.org/r/1524212968-28998-1-git-send-email-davidwang@zhaoxin.com
2018-04-20 12:08:17 +02:00
Thomas Gleixner
1cfd904f16 y2038: timekeeping syscall changes
This is the first set of system call entry point changes to enable 32-bit
 architectures to have variants on both 32-bit and 64-bit time_t. Typically
 these system calls take a 'struct timespec' argument, but that structure
 is defined in user space by the C library and its layout will change.
 
 The kernel already supports handling the 32-bit time_t on 64-bit
 architectures through the CONFIG_COMPAT mechanism. As there are a total
 of 51 system calls suffering from this problem, reusing that mechanism
 on 32-bit architectures.
 
 We already have patches for most of the remaining system calls, but this
 set contains most of the complexity and is best tested.  There was one
 last-minute regression that prevented it from going into 4.17, but that
 is fixed now.
 
 More details from Deepa's patch series description:
 
    Big picture is as per the lwn article:
    https://lwn.net/Articles/643234/ [2]
 
    The series is directed at converting posix clock syscalls:
    clock_gettime, clock_settime, clock_getres and clock_nanosleep
    to use a new data structure __kernel_timespec at syscall boundaries.
    __kernel_timespec maintains 64 bit time_t across all execution modes.
 
    vdso will be handled as part of each architecture when they enable
    support for 64 bit time_t.
 
    The compat syscalls are repurposed to provide backward compatibility
    by using them as native syscalls as well for 32 bit architectures.
    They will continue to use timespec at syscall boundaries.
 
    CONFIG_64_BIT_TIME controls whether the syscalls use __kernel_timespec
    or timespec at syscall boundaries.
 
    The series does the following:
    1. Enable compat syscalls on 32 bit architectures.
    2. Add a new __kernel_timespec type to be used as the data structure
       for all the new syscalls.
    3. Add new config CONFIG_64BIT_TIME(intead of the CONFIG_COMPAT_TIME in
       [1] and [2] to switch to new definition of __kernel_timespec. It is
       the same as struct timespec otherwise.
    4. Add new CONFIG_32BIT_TIME to conditionally compile compat syscalls.
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Merge tag 'y2038-timekeeping' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/playground into timers/core

Pull y2038 timekeeping syscall changes from Arnd Bergmann:

This is the first set of system call entry point changes to enable 32-bit
architectures to have variants on both 32-bit and 64-bit time_t. Typically
these system calls take a 'struct timespec' argument, but that structure
is defined in user space by the C library and its layout will change.

The kernel already supports handling the 32-bit time_t on 64-bit
architectures through the CONFIG_COMPAT mechanism. As there are a total
of 51 system calls suffering from this problem, reusing that mechanism
on 32-bit architectures.

We already have patches for most of the remaining system calls, but this
set contains most of the complexity and is best tested.  There was one
last-minute regression that prevented it from going into 4.17, but that
is fixed now.

More details from Deepa's patch series description:

   Big picture is as per the lwn article:
   https://lwn.net/Articles/643234/ [2]

   The series is directed at converting posix clock syscalls:
   clock_gettime, clock_settime, clock_getres and clock_nanosleep
   to use a new data structure __kernel_timespec at syscall boundaries.
   __kernel_timespec maintains 64 bit time_t across all execution modes.

   vdso will be handled as part of each architecture when they enable
   support for 64 bit time_t.

   The compat syscalls are repurposed to provide backward compatibility
   by using them as native syscalls as well for 32 bit architectures.
   They will continue to use timespec at syscall boundaries.

   CONFIG_64_BIT_TIME controls whether the syscalls use __kernel_timespec
   or timespec at syscall boundaries.

   The series does the following:
   1. Enable compat syscalls on 32 bit architectures.
   2. Add a new __kernel_timespec type to be used as the data structure
      for all the new syscalls.
   3. Add new config CONFIG_64BIT_TIME(intead of the CONFIG_COMPAT_TIME in
      [1] and [2] to switch to new definition of __kernel_timespec. It is
      the same as struct timespec otherwise.
   4. Add new CONFIG_32BIT_TIME to conditionally compile compat syscalls.
2018-04-19 16:27:44 +02:00
Deepa Dinamani
0d55303c51 compat: Move compat_timespec/ timeval to compat_time.h
All the current architecture specific defines for these
are the same. Refactor these common defines to a common
header file.

The new common linux/compat_time.h is also useful as it
will eventually be used to hold all the defines that
are needed for compat time types that support non y2038
safe types. New architectures need not have to define these
new types as they will only use new y2038 safe syscalls.
This file can be deleted after y2038 when we stop supporting
non y2038 safe syscalls.

The patch also requires an operation similar to:

git grep "asm/compat\.h" | cut -d ":" -f 1 |  xargs -n 1 sed -i -e "s%asm/compat.h%linux/compat.h%g"

Cc: acme@kernel.org
Cc: benh@kernel.crashing.org
Cc: borntraeger@de.ibm.com
Cc: catalin.marinas@arm.com
Cc: cmetcalf@mellanox.com
Cc: cohuck@redhat.com
Cc: davem@davemloft.net
Cc: deller@gmx.de
Cc: devel@driverdev.osuosl.org
Cc: gerald.schaefer@de.ibm.com
Cc: gregkh@linuxfoundation.org
Cc: heiko.carstens@de.ibm.com
Cc: hoeppner@linux.vnet.ibm.com
Cc: hpa@zytor.com
Cc: jejb@parisc-linux.org
Cc: jwi@linux.vnet.ibm.com
Cc: linux-kernel@vger.kernel.org
Cc: linux-mips@linux-mips.org
Cc: linux-parisc@vger.kernel.org
Cc: linuxppc-dev@lists.ozlabs.org
Cc: linux-s390@vger.kernel.org
Cc: mark.rutland@arm.com
Cc: mingo@redhat.com
Cc: mpe@ellerman.id.au
Cc: oberpar@linux.vnet.ibm.com
Cc: oprofile-list@lists.sf.net
Cc: paulus@samba.org
Cc: peterz@infradead.org
Cc: ralf@linux-mips.org
Cc: rostedt@goodmis.org
Cc: rric@kernel.org
Cc: schwidefsky@de.ibm.com
Cc: sebott@linux.vnet.ibm.com
Cc: sparclinux@vger.kernel.org
Cc: sth@linux.vnet.ibm.com
Cc: ubraun@linux.vnet.ibm.com
Cc: will.deacon@arm.com
Cc: x86@kernel.org
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com>
Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: James Hogan <jhogan@kernel.org>
Acked-by: Helge Deller <deller@gmx.de>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2018-04-19 13:29:54 +02:00
Alison Schofield
1340ccfa9a x86,sched: Allow topologies where NUMA nodes share an LLC
Intel's Skylake Server CPUs have a different LLC topology than previous
generations. When in Sub-NUMA-Clustering (SNC) mode, the package is divided
into two "slices", each containing half the cores, half the LLC, and one
memory controller and each slice is enumerated to Linux as a NUMA
node. This is similar to how the cores and LLC were arranged for the
Cluster-On-Die (CoD) feature.

CoD allowed the same cache line to be present in each half of the LLC.
But, with SNC, each line is only ever present in *one* slice. This means
that the portion of the LLC *available* to a CPU depends on the data being
accessed:

    Remote socket: entire package LLC is shared
    Local socket->local slice: data goes into local slice LLC
    Local socket->remote slice: data goes into remote-slice LLC. Slightly
                    		higher latency than local slice LLC.

The biggest implication from this is that a process accessing all
NUMA-local memory only sees half the LLC capacity.

The CPU describes its cache hierarchy with the CPUID instruction. One of
the CPUID leaves enumerates the "logical processors sharing this
cache". This information is used for scheduling decisions so that tasks
move more freely between CPUs sharing the cache.

But, the CPUID for the SNC configuration discussed above enumerates the LLC
as being shared by the entire package. This is not 100% precise because the
entire cache is not usable by all accesses. But, it *is* the way the
hardware enumerates itself, and this is not likely to change.

The userspace visible impact of all the above is that the sysfs info
reports the entire LLC as being available to the entire package. As noted
above, this is not true for local socket accesses. This patch does not
correct the sysfs info. It is the same, pre and post patch.

The current code emits the following warning:

 sched: CPU #3's llc-sibling CPU #0 is not on the same node! [node: 1 != 0]. Ignoring dependency.

The warning is coming from the topology_sane() check in smpboot.c because
the topology is not matching the expectations of the model for obvious
reasons.

To fix this, add a vendor and model specific check to never call
topology_sane() for these systems. Also, just like "Cluster-on-Die" disable
the "coregroup" sched_domain_topology_level and use NUMA information from
the SRAT alone.

This is OK at least on the hardware we are immediately concerned about
because the LLC sharing happens at both the slice and at the package level,
which are also NUMA boundaries.

Signed-off-by: Alison Schofield <alison.schofield@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Borislav Petkov <bp@suse.de>
Cc: Prarit Bhargava <prarit@redhat.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: brice.goglin@gmail.com
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: David Rientjes <rientjes@google.com>
Cc: Igor Mammedov <imammedo@redhat.com>
Cc: "H. Peter Anvin" <hpa@linux.intel.com>
Cc: Tim Chen <tim.c.chen@linux.intel.com>
Link: https://lkml.kernel.org/r/20180407002130.GA18984@alison-desk.jf.intel.com
2018-04-17 15:39:55 +02:00
Dou Liyang
10daf10ab1 x86/acpi: Prevent X2APIC id 0xffffffff from being accounted
RongQing reported that there are some X2APIC id 0xffffffff in his machine's
ACPI MADT table, which makes the number of possible CPU inaccurate.

The reason is that the ACPI X2APIC parser has no sanity check for APIC ID
0xffffffff, which is an invalid id in all APIC types. See "Intel® 64
Architecture x2APIC Specification", Chapter 2.4.1.

Add a sanity check to acpi_parse_x2apic() which ignores the invalid id.

Reported-by: Li RongQing <lirongqing@baidu.com>
Signed-off-by: Dou Liyang <douly.fnst@cn.fujitsu.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Cc: len.brown@intel.com
Cc: rjw@rjwysocki.net
Cc: hpa@zytor.com
Link: https://lkml.kernel.org/r/20180412014052.25186-1-douly.fnst@cn.fujitsu.com
2018-04-17 11:56:31 +02:00
Xiaoming Gao
d3878e164d x86/tsc: Prevent 32bit truncation in calc_hpet_ref()
The TSC calibration code uses HPET as reference. The conversion normalizes
the delta of two HPET timestamps:

    hpetref = ((tshpet1 - tshpet2) * HPET_PERIOD) / 1e6

and then divides the normalized delta of the corresponding TSC timestamps
by the result to calulate the TSC frequency.

    tscfreq = ((tstsc1 - tstsc2 ) * 1e6) / hpetref

This uses do_div() which takes an u32 as the divisor, which worked so far
because the HPET frequency was low enough that 'hpetref' never exceeded
32bit.

On Skylake machines the HPET frequency increased so 'hpetref' can exceed
32bit. do_div() truncates the divisor, which causes the calibration to
fail.

Use div64_u64() to avoid the problem.

[ tglx: Fixes whitespace mangled patch and rewrote changelog ]

Signed-off-by: Xiaoming Gao <newtongao@tencent.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Cc: peterz@infradead.org
Cc: hpa@zytor.com
Link: https://lkml.kernel.org/r/38894564-4fc9-b8ec-353f-de702839e44e@gmail.com
2018-04-17 11:50:42 +02:00
Christoph Hellwig
ef97837db9 x86: Remove pci-nommu.c
The commit that switched x86 to dma_direct_ops stopped using and building
this file, but accidentally left it in the tree.  Remove it.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: iommu@lists.infradead.org
Link: https://lkml.kernel.org/r/20180416124442.13831-1-hch@lst.de
2018-04-17 11:48:06 +02:00
Joerg Roedel
e6f39e87b6 x86/ldt: Fix support_pte_mask filtering in map_ldt_struct()
The |= operator will let us end up with an invalid PTE. Use
the correct &= instead.

[ The bug was also independently reported by Shuah Khan ]

Fixes: fb43d6cb91 ('x86/mm: Do not auto-massage page protections')
Acked-by: Andy Lutomirski <luto@kernel.org>
Acked-by: Dave Hansen <dave.hansen@linux.intel.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-16 11:20:34 -07:00
Linus Torvalds
9fb71c2f23 Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fixes from Thomas Gleixner:
 "A set of fixes and updates for x86:

   - Address a swiotlb regression which was caused by the recent DMA
     rework and made driver fail because dma_direct_supported() returned
     false

   - Fix a signedness bug in the APIC ID validation which caused invalid
     APIC IDs to be detected as valid thereby bloating the CPU possible
     space.

   - Fix inconsisten config dependcy/select magic for the MFD_CS5535
     driver.

   - Fix a corruption of the physical address space bits when encryption
     has reduced the address space and late cpuinfo updates overwrite
     the reduced bit information with the original value.

   - Dominiks syscall rework which consolidates the architecture
     specific syscall functions so all syscalls can be wrapped with the
     same macros. This allows to switch x86/64 to struct pt_regs based
     syscalls. Extend the clearing of user space controlled registers in
     the entry patch to the lower registers"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/apic: Fix signedness bug in APIC ID validity checks
  x86/cpu: Prevent cpuinfo_x86::x86_phys_bits adjustment corruption
  x86/olpc: Fix inconsistent MFD_CS5535 configuration
  swiotlb: Use dma_direct_supported() for swiotlb_ops
  syscalls/x86: Adapt syscall_wrapper.h to the new syscall stub naming convention
  syscalls/core, syscalls/x86: Rename struct pt_regs-based sys_*() to __x64_sys_*()
  syscalls/core, syscalls/x86: Clean up compat syscall stub naming convention
  syscalls/core, syscalls/x86: Clean up syscall stub naming convention
  syscalls/x86: Extend register clearing on syscall entry to lower registers
  syscalls/x86: Unconditionally enable 'struct pt_regs' based syscalls on x86_64
  syscalls/x86: Use 'struct pt_regs' based syscall calling for IA32_EMULATION and x32
  syscalls/core: Prepare CONFIG_ARCH_HAS_SYSCALL_WRAPPER=y for compat syscalls
  syscalls/x86: Use 'struct pt_regs' based syscall calling convention for 64-bit syscalls
  syscalls/core: Introduce CONFIG_ARCH_HAS_SYSCALL_WRAPPER=y
  x86/syscalls: Don't pointlessly reload the system call number
  x86/mm: Fix documentation of module mapping range with 4-level paging
  x86/cpuid: Switch to 'static const' specifier
2018-04-15 16:12:35 -07:00
Linus Torvalds
6b0a02e86c Merge branch 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 pti updates from Thomas Gleixner:
 "Another series of PTI related changes:

   - Remove the manual stack switch for user entries from the idtentry
     code. This debloats entry by 5k+ bytes of text.

   - Use the proper types for the asm/bootparam.h defines to prevent
     user space compile errors.

   - Use PAGE_GLOBAL for !PCID systems to gain back performance

   - Prevent setting of huge PUD/PMD entries when the entries are not
     leaf entries otherwise the entries to which the PUD/PMD points to
     and are populated get lost"

* 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/pgtable: Don't set huge PUD/PMD on non-leaf entries
  x86/pti: Leave kernel text global for !PCID
  x86/pti: Never implicitly clear _PAGE_GLOBAL for kernel image
  x86/pti: Enable global pages for shared areas
  x86/mm: Do not forbid _PAGE_RW before init for __ro_after_init
  x86/mm: Comment _PAGE_GLOBAL mystery
  x86/mm: Remove extra filtering in pageattr code
  x86/mm: Do not auto-massage page protections
  x86/espfix: Document use of _PAGE_GLOBAL
  x86/mm: Introduce "default" kernel PTE mask
  x86/mm: Undo double _PAGE_PSE clearing
  x86/mm: Factor out pageattr _PAGE_GLOBAL setting
  x86/entry/64: Drop idtentry's manual stack switch for user entries
  x86/uapi: Fix asm/bootparam.h userspace compilation errors
2018-04-15 13:35:29 -07:00
Philipp Rudo
3be3f61d25 kernel/kexec_file.c: allow archs to set purgatory load address
For s390 new kernels are loaded to fixed addresses in memory before they
are booted.  With the current code this is a problem as it assumes the
kernel will be loaded to an 'arbitrary' address.  In particular,
kexec_locate_mem_hole searches for a large enough memory region and sets
the load address (kexec_bufer->mem) to it.

Luckily there is a simple workaround for this problem.  By returning 1
in arch_kexec_walk_mem, kexec_locate_mem_hole is turned off.  This
allows the architecture to set kbuf->mem by hand.  While the trick works
fine for the kernel it does not for the purgatory as here the
architectures don't have access to its kexec_buffer.

Give architectures access to the purgatories kexec_buffer by changing
kexec_load_purgatory to take a pointer to it.  With this change
architectures have access to the buffer and can edit it as they need.

A nice side effect of this change is that we can get rid of the
purgatory_info->purgatory_load_address field.  As now the information
stored there can directly be accessed from kbuf->mem.

Link: http://lkml.kernel.org/r/20180321112751.22196-11-prudo@linux.vnet.ibm.com
Signed-off-by: Philipp Rudo <prudo@linux.vnet.ibm.com>
Reviewed-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Acked-by: Dave Young <dyoung@redhat.com>
Cc: AKASHI Takahiro <takahiro.akashi@linaro.org>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-13 17:10:28 -07:00
Philipp Rudo
8da0b72495 kernel/kexec_file.c: remove mis-use of sh_offset field during purgatory load
The current code uses the sh_offset field in purgatory_info->sechdrs to
store a pointer to the current load address of the section.  Depending
whether the section will be loaded or not this is either a pointer into
purgatory_info->purgatory_buf or kexec_purgatory.  This is not only a
violation of the ELF standard but also makes the code very hard to
understand as you cannot tell if the memory you are using is read-only
or not.

Remove this misuse and store the offset of the section in
pugaroty_info->purgatory_buf in sh_offset.

Link: http://lkml.kernel.org/r/20180321112751.22196-10-prudo@linux.vnet.ibm.com
Signed-off-by: Philipp Rudo <prudo@linux.vnet.ibm.com>
Acked-by: Dave Young <dyoung@redhat.com>
Cc: AKASHI Takahiro <takahiro.akashi@linaro.org>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-13 17:10:28 -07:00
Philipp Rudo
8aec395b84 kernel/kexec_file.c: use read-only sections in arch_kexec_apply_relocations*
When the relocations are applied to the purgatory only the section the
relocations are applied to is writable.  The other sections, i.e.  the
symtab and .rel/.rela, are in read-only kexec_purgatory.  Highlight this
by marking the corresponding variables as 'const'.

While at it also change the signatures of arch_kexec_apply_relocations* to
take section pointers instead of just the index of the relocation section.
This removes the second lookup and sanity check of the sections in arch
code.

Link: http://lkml.kernel.org/r/20180321112751.22196-6-prudo@linux.vnet.ibm.com
Signed-off-by: Philipp Rudo <prudo@linux.vnet.ibm.com>
Acked-by: Dave Young <dyoung@redhat.com>
Cc: AKASHI Takahiro <takahiro.akashi@linaro.org>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-13 17:10:28 -07:00
AKASHI Takahiro
babac4a84a kexec_file, x86: move re-factored code to generic side
In the previous patches, commonly-used routines, exclude_mem_range() and
prepare_elf64_headers(), were carved out.  Now place them in kexec
common code.  A prefix "crash_" is given to each of their names to avoid
possible name collisions.

Link: http://lkml.kernel.org/r/20180306102303.9063-8-takahiro.akashi@linaro.org
Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
Acked-by: Dave Young <dyoung@redhat.com>
Tested-by: Dave Young <dyoung@redhat.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Baoquan He <bhe@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-13 17:10:27 -07:00
AKASHI Takahiro
eb7dae947e x86: kexec_file: clean up prepare_elf64_headers()
Removing bufp variable in prepare_elf64_headers() makes the code simpler
and more understandable.

Link: http://lkml.kernel.org/r/20180306102303.9063-7-takahiro.akashi@linaro.org
Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
Acked-by: Dave Young <dyoung@redhat.com>
Tested-by: Dave Young <dyoung@redhat.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Baoquan He <bhe@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-13 17:10:27 -07:00
AKASHI Takahiro
8d5f894a31 x86: kexec_file: lift CRASH_MAX_RANGES limit on crash_mem buffer
While CRASH_MAX_RANGES (== 16) seems to be good enough, fixed-number
array is not a good idea in general.

In this patch, size of crash_mem buffer is calculated as before and the
buffer is now dynamically allocated.  This change also allows removing
crash_elf_data structure.

Link: http://lkml.kernel.org/r/20180306102303.9063-6-takahiro.akashi@linaro.org
Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
Acked-by: Dave Young <dyoung@redhat.com>
Tested-by: Dave Young <dyoung@redhat.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Baoquan He <bhe@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-13 17:10:27 -07:00
AKASHI Takahiro
c72c7e6709 x86: kexec_file: remove X86_64 dependency from prepare_elf64_headers()
The code guarded by CONFIG_X86_64 is necessary on some architectures
which have a dedicated kernel mapping outside of linear memory mapping.
(arm64 is among those.)

In this patch, an additional argument, kernel_map, is added to enable/
disable the code removing #ifdef.

Link: http://lkml.kernel.org/r/20180306102303.9063-5-takahiro.akashi@linaro.org
Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
Acked-by: Dave Young <dyoung@redhat.com>
Tested-by: Dave Young <dyoung@redhat.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Baoquan He <bhe@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-13 17:10:27 -07:00
AKASHI Takahiro
cbe6601617 x86: kexec_file: purge system-ram walking from prepare_elf64_headers()
While prepare_elf64_headers() in x86 looks pretty generic for other
architectures' use, it contains some code which tries to list crash
memory regions by walking through system resources, which is not always
architecture agnostic.  To make this function more generic, the related
code should be purged.

In this patch, prepare_elf64_headers() simply scans crash_mem buffer
passed and add all the listed regions to elf header as a PT_LOAD
segment.  So walk_system_ram_res(prepare_elf64_headers_callback) have
been moved forward before prepare_elf64_headers() where the callback,
prepare_elf64_headers_callback(), is now responsible for filling up
crash_mem buffer.

Meanwhile exclude_elf_header_ranges() used to be called every time in
this callback it is rather redundant and now called only once in
prepare_elf_headers() as well.

Link: http://lkml.kernel.org/r/20180306102303.9063-4-takahiro.akashi@linaro.org
Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
Acked-by: Dave Young <dyoung@redhat.com>
Tested-by: Dave Young <dyoung@redhat.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Baoquan He <bhe@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-13 17:10:27 -07:00
AKASHI Takahiro
9ec4ecef0a kexec_file,x86,powerpc: factor out kexec_file_ops functions
As arch_kexec_kernel_image_{probe,load}(),
arch_kimage_file_post_load_cleanup() and arch_kexec_kernel_verify_sig()
are almost duplicated among architectures, they can be commonalized with
an architecture-defined kexec_file_ops array.  So let's factor them out.

Link: http://lkml.kernel.org/r/20180306102303.9063-3-takahiro.akashi@linaro.org
Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
Acked-by: Dave Young <dyoung@redhat.com>
Tested-by: Dave Young <dyoung@redhat.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-13 17:10:27 -07:00
Linus Torvalds
681857ef0d Merge branch 'parisc-4.17-2' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux
Pull parisc updates from Helge Deller:

 - fix panic when halting system via "shutdown -h now"

 - drop own coding in favour of generic CONFIG_COMPAT_BINFMT_ELF
   implementation

 - add FPE_CONDTRAP constant: last outstanding parisc-specific cleanup
   for Eric Biedermans siginfo patches

 - move some functions to .init and some to .text.hot linker sections

* 'parisc-4.17-2' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux:
  parisc: Prevent panic at system halt
  parisc: Switch to generic COMPAT_BINFMT_ELF
  parisc: Move cache flush functions into .text.hot section
  parisc/signal: Add FPE_CONDTRAP for conditional trap handling
2018-04-12 17:07:04 -07:00
Ingo Molnar
ef389b7346 Merge branch 'WIP.x86/asm' into x86/urgent, because the topic is ready
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-04-12 09:42:34 +02:00
Dave Hansen
430d4005b8 x86/mm: Comment _PAGE_GLOBAL mystery
I was mystified as to where the _PAGE_GLOBAL in the kernel page tables
for kernel text came from.  I audited all the places I could find, but
I missed one: head_64.S.

The page tables that we create in here live for a long time, and they
also have _PAGE_GLOBAL set, despite whether the processor supports it
or not.  It's harmless, and we got *lucky* that the pageattr code
accidentally clears it when we wipe it out of __supported_pte_mask and
then later try to mark kernel text read-only.

Comment some of these properties to make it easier to find and
understand in the future.

Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Hugh Dickins <hughd@google.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Kees Cook <keescook@google.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Nadav Amit <namit@vmware.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/20180406205513.079BB265@viggo.jf.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-04-12 09:05:58 +02:00