linux.git/arch/x86/kernel/cpu/intel.c, branch v5.6 Linux kernel source tree Merge tag 'mpx-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/daveh/x86-mpx 2020-01-31T00:11:50+00:00 Linus Torvalds torvalds@linux-foundation.org 2020-01-31T00:11:50+00:00 ccaaaf6fe5a5e1fffca5cca0f3fc4ec84d7ae752 Pull x86 MPX removal from Dave Hansen: "MPX requires recompiling applications, which requires compiler support. Unfortunately, GCC 9.1 is expected to be be released without support for MPX. This means that there was only a relatively small window where folks could have ever used MPX. It failed to gain wide adoption in the industry, and Linux was the only mainstream OS to ever support it widely. Support for the feature may also disappear on future processors. This set completes the process that we started during the 5.4 merge window when the MPX prctl()s were removed. XSAVE support is left in place, which allows MPX-using KVM guests to continue to function" * tag 'mpx-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/daveh/x86-mpx: x86/mpx: remove MPX from arch/x86 mm: remove arch_bprm_mm_init() hook x86/mpx: remove bounds exception code x86/mpx: remove build infrastructure x86/alternatives: add missing insn.h include 
Pull x86 MPX removal from Dave Hansen:
 "MPX requires recompiling applications, which requires compiler
  support. Unfortunately, GCC 9.1 is expected to be be released without
  support for MPX. This means that there was only a relatively small
  window where folks could have ever used MPX. It failed to gain wide
  adoption in the industry, and Linux was the only mainstream OS to ever
  support it widely.

  Support for the feature may also disappear on future processors.

  This set completes the process that we started during the 5.4 merge
  window when the MPX prctl()s were removed. XSAVE support is left in
  place, which allows MPX-using KVM guests to continue to function"

* tag 'mpx-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/daveh/x86-mpx:
  x86/mpx: remove MPX from arch/x86
  mm: remove arch_bprm_mm_init() hook
  x86/mpx: remove bounds exception code
  x86/mpx: remove build infrastructure
  x86/alternatives: add missing insn.h include
x86/mpx: remove MPX from arch/x86 2020-01-23T18:41:20+00:00 Dave Hansen dave.hansen@linux.intel.com 2020-01-23T18:41:20+00:00 45fc24e89b7cc2e227b2f03d99dda0a2204bf383 From: Dave Hansen <dave.hansen@linux.intel.com> MPX is being removed from the kernel due to a lack of support in the toolchain going forward (gcc). This removes all the remaining (dead at this point) MPX handling code remaining in the tree. The only remaining code is the XSAVE support for MPX state which is currently needd for KVM to handle VMs which might use MPX. Cc: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Andy Lutomirski <luto@kernel.org> Cc: x86@kernel.org Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> 
From: Dave Hansen <dave.hansen@linux.intel.com>

MPX is being removed from the kernel due to a lack of support
in the toolchain going forward (gcc).

This removes all the remaining (dead at this point) MPX handling
code remaining in the tree.  The only remaining code is the XSAVE
support for MPX state which is currently needd for KVM to handle
VMs which might use MPX.

Cc: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: x86@kernel.org
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
x86/cpu: Set synthetic VMX cpufeatures during init_ia32_feat_ctl() 2020-01-13T17:43:19+00:00 Sean Christopherson sean.j.christopherson@intel.com 2019-12-21T04:45:06+00:00 167a4894c113ebe6a1f8b24fa6f9fca849c77f8a Set the synthetic VMX cpufeatures, which need to be kept to preserve /proc/cpuinfo's ABI, in the common IA32_FEAT_CTL initialization code. Remove the vendor code that manually sets the synthetic flags. Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Link: https://lkml.kernel.org/r/20191221044513.21680-13-sean.j.christopherson@intel.com 
Set the synthetic VMX cpufeatures, which need to be kept to preserve
/proc/cpuinfo's ABI, in the common IA32_FEAT_CTL initialization code.
Remove the vendor code that manually sets the synthetic flags.

Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20191221044513.21680-13-sean.j.christopherson@intel.com
x86/intel: Initialize IA32_FEAT_CTL MSR at boot 2020-01-13T16:45:45+00:00 Sean Christopherson sean.j.christopherson@intel.com 2019-12-21T04:44:58+00:00 1db2a6e1e29ff994443a9eef7cf3d26104c777a7 Opportunistically initialize IA32_FEAT_CTL to enable VMX when the MSR is left unlocked by BIOS. Configuring feature control at boot time paves the way for similar enabling of other features, e.g. Software Guard Extensions (SGX). Temporarily leave equivalent KVM code in place in order to avoid introducing a regression on Centaur and Zhaoxin CPUs, e.g. removing KVM's code would leave the MSR unlocked on those CPUs and would break existing functionality if people are loading kvm_intel on Centaur and/or Zhaoxin. Defer enablement of the boot-time configuration on Centaur and Zhaoxin to future patches to aid bisection. Note, Local Machine Check Exceptions (LMCE) are also supported by the kernel and enabled via feature control, but the kernel currently uses LMCE if and only if the feature is explicitly enabled by BIOS. Keep the current behavior to avoid introducing bugs, future patches can opt in to opportunistic enabling if it's deemed desirable to do so. Always lock IA32_FEAT_CTL if it exists, even if the CPU doesn't support VMX, so that other existing and future kernel code that queries the MSR can assume it's locked. Start from a clean slate when constructing the value to write to IA32_FEAT_CTL, i.e. ignore whatever value BIOS left in the MSR so as not to enable random features or fault on the WRMSR. Suggested-by: Borislav Petkov <bp@suse.de> Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Link: https://lkml.kernel.org/r/20191221044513.21680-5-sean.j.christopherson@intel.com 
Opportunistically initialize IA32_FEAT_CTL to enable VMX when the MSR is
left unlocked by BIOS.  Configuring feature control at boot time paves
the way for similar enabling of other features, e.g. Software Guard
Extensions (SGX).

Temporarily leave equivalent KVM code in place in order to avoid
introducing a regression on Centaur and Zhaoxin CPUs, e.g. removing
KVM's code would leave the MSR unlocked on those CPUs and would break
existing functionality if people are loading kvm_intel on Centaur and/or
Zhaoxin.  Defer enablement of the boot-time configuration on Centaur and
Zhaoxin to future patches to aid bisection.

Note, Local Machine Check Exceptions (LMCE) are also supported by the
kernel and enabled via feature control, but the kernel currently uses
LMCE if and only if the feature is explicitly enabled by BIOS.  Keep
the current behavior to avoid introducing bugs, future patches can opt
in to opportunistic enabling if it's deemed desirable to do so.

Always lock IA32_FEAT_CTL if it exists, even if the CPU doesn't support
VMX, so that other existing and future kernel code that queries the MSR
can assume it's locked.

Start from a clean slate when constructing the value to write to
IA32_FEAT_CTL, i.e. ignore whatever value BIOS left in the MSR so as not
to enable random features or fault on the WRMSR.

Suggested-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20191221044513.21680-5-sean.j.christopherson@intel.com
Merge tag 'v5.4-rc8' into WIP.x86/mm, to pick up fixes 2019-11-19T08:00:45+00:00 Ingo Molnar mingo@kernel.org 2019-11-19T08:00:45+00:00 9f4813b531a0b8cc502fcfb142937fe4e9104d77 Signed-off-by: Ingo Molnar <mingo@kernel.org> 
Signed-off-by: Ingo Molnar <mingo@kernel.org>
x86/cpu: Add a "tsx=" cmdline option with TSX disabled by default 2019-10-28T07:36:58+00:00 Pawan Gupta pawan.kumar.gupta@linux.intel.com 2019-10-23T09:01:53+00:00 95c5824f75f3ba4c9e8e5a4b1a623c95390ac266 Add a kernel cmdline parameter "tsx" to control the Transactional Synchronization Extensions (TSX) feature. On CPUs that support TSX control, use "tsx=on|off" to enable or disable TSX. Not specifying this option is equivalent to "tsx=off". This is because on certain processors TSX may be used as a part of a speculative side channel attack. Carve out the TSX controlling functionality into a separate compilation unit because TSX is a CPU feature while the TSX async abort control machinery will go to cpu/bugs.c. [ bp: - Massage, shorten and clear the arg buffer. - Clarifications of the tsx= possible options - Josh. - Expand on TSX_CTRL availability - Pawan. ] Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com> 
Add a kernel cmdline parameter "tsx" to control the Transactional
Synchronization Extensions (TSX) feature. On CPUs that support TSX
control, use "tsx=on|off" to enable or disable TSX. Not specifying this
option is equivalent to "tsx=off". This is because on certain processors
TSX may be used as a part of a speculative side channel attack.

Carve out the TSX controlling functionality into a separate compilation
unit because TSX is a CPU feature while the TSX async abort control
machinery will go to cpu/bugs.c.

 [ bp: - Massage, shorten and clear the arg buffer.
       - Clarifications of the tsx= possible options - Josh.
       - Expand on TSX_CTRL availability - Pawan. ]

Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com>
x86/cpu: Clean up intel_tlb_table[] 2019-09-16T15:23:46+00:00 Sylvain 'ythier' Hitier sylvain.hitier@gmail.com 2019-09-15T09:09:25+00:00 77df779de742d6616d4ddd177cba152a75259104 - Remove the unneeded backslash at EOL: that's not a macro. And let's please checkpatch by aligning to open parenthesis. - For 0x4f descriptor, remove " */" from the info field. - For 0xc2 descriptor, sync the beginning of info to match the tlb_type. (The value of info fields could be made more regular, but it's unused by the code and will be read only by developers, so don't bother.) Signed-off-by: Sylvain 'ythier' Hitier <sylvain.hitier@gmail.com> Cc: Alex Shi <alex.shi@intel.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Hans de Goede <hdegoede@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Cc: Ricardo Neri <ricardo.neri-calderon@linux.intel.com> Cc: Rik van Riel <riel@surriel.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: trivial@kernel.org Link: https://lkml.kernel.org/r/20190915090917.GA5086@lilas Signed-off-by: Ingo Molnar <mingo@kernel.org> 
- Remove the unneeded backslash at EOL: that's not a macro.
  And let's please checkpatch by aligning to open parenthesis.

- For 0x4f descriptor, remove " */" from the info field.

- For 0xc2 descriptor, sync the beginning of info to match the tlb_type.

(The value of info fields could be made more regular, but it's unused by
 the code and will be read only by developers, so don't bother.)

Signed-off-by: Sylvain 'ythier' Hitier <sylvain.hitier@gmail.com>
Cc: Alex Shi <alex.shi@intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Hans de Goede <hdegoede@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: Ricardo Neri <ricardo.neri-calderon@linux.intel.com>
Cc: Rik van Riel <riel@surriel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: trivial@kernel.org
Link: https://lkml.kernel.org/r/20190915090917.GA5086@lilas
Signed-off-by: Ingo Molnar <mingo@kernel.org>
x86/cpu: Update init data for new Airmont CPU model 2019-09-06T05:30:40+00:00 Rahul Tanwar rahul.tanwar@linux.intel.com 2019-09-05T19:30:20+00:00 0cc5359d8fd45bc410906e009117e78e2b5b2322 Update properties for newly added Airmont CPU variant. Signed-off-by: Rahul Tanwar <rahul.tanwar@linux.intel.com> Signed-off-by: Tony Luck <tony.luck@intel.com> Cc: Gayatri Kammela <gayatri.kammela@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/20190905193020.14707-5-tony.luck@intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org> 
Update properties for newly added Airmont CPU variant.

Signed-off-by: Rahul Tanwar <rahul.tanwar@linux.intel.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Cc: Gayatri Kammela <gayatri.kammela@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20190905193020.14707-5-tony.luck@intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Merge branch 'x86/cleanups' into x86/cpu, to pick up dependent changes 2019-09-06T05:30:23+00:00 Ingo Molnar mingo@kernel.org 2019-09-06T05:30:23+00:00 9326011edfcb7f7c3ad70f8a1cde6b391604808e Signed-off-by: Ingo Molnar <mingo@kernel.org> 
Signed-off-by: Ingo Molnar <mingo@kernel.org>
x86/intel: Aggregate microserver naming 2019-08-28T09:29:32+00:00 Peter Zijlstra peterz@infradead.org 2019-08-27T19:48:24+00:00 5ebb34edbefa8ea6a7e109179d5fc7b3529dbeba Currently big microservers have _XEON_D while small microservers have _X, Make it uniformly: _D. for i in `git grep -l "\(INTEL_FAM6_\|VULNWL_INTEL\|INTEL_CPU_FAM6\).*_\(X\|XEON_D\)"` do sed -i -e 's/\(\(INTEL_FAM6_\|VULNWL_INTEL\|INTEL_CPU_FAM6\).*ATOM.*\)_X/\1_D/g' \ -e 's/\(\(INTEL_FAM6_\|VULNWL_INTEL\|INTEL_CPU_FAM6\).*\)_XEON_D/\1_D/g' ${i} done Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Tony Luck <tony.luck@intel.com> Cc: x86@kernel.org Cc: Dave Hansen <dave.hansen@intel.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Borislav Petkov <bp@alien8.de> Link: https://lkml.kernel.org/r/20190827195122.677152989@infradead.org 
Currently big microservers have _XEON_D while small microservers have
_X, Make it uniformly: _D.

for i in `git grep -l "\(INTEL_FAM6_\|VULNWL_INTEL\|INTEL_CPU_FAM6\).*_\(X\|XEON_D\)"`
do
	sed -i -e 's/\(\(INTEL_FAM6_\|VULNWL_INTEL\|INTEL_CPU_FAM6\).*ATOM.*\)_X/\1_D/g' \
	       -e 's/\(\(INTEL_FAM6_\|VULNWL_INTEL\|INTEL_CPU_FAM6\).*\)_XEON_D/\1_D/g' ${i}
done

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Cc: x86@kernel.org
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Borislav Petkov <bp@alien8.de>
Link: https://lkml.kernel.org/r/20190827195122.677152989@infradead.org