There's a risk that a kernel which has full retpoline mitigations becomes
vulnerable when a module gets loaded that hasn't been compiled with the
right compiler or the right option.
To enable detection of that mismatch at module load time, add a module info
string "retpoline" at build time when the module was compiled with
retpoline support. This only covers compiled C source, but assembler source
or prebuilt object files are not checked.
If a retpoline enabled kernel detects a non retpoline protected module at
load time, print a warning and report it in the sysfs vulnerability file.
[ tglx: Massaged changelog ]
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: gregkh@linuxfoundation.org
Cc: torvalds@linux-foundation.org
Cc: jeyu@kernel.org
Cc: arjan@linux.intel.com
Link: https://lkml.kernel.org/r/20180125235028.31211-1-andi@firstfloor.org
Centaur CPU has a constant frequency TSC and that TSC does not stop in
C-States. But because the corresponding TSC feature flags are not set for
that CPU, the TSC is treated as not constant frequency and assumed to stop
in C-States, which makes it an unreliable and unusable clock source.
Setting those flags tells the kernel that the TSC is usable, so it will
select it over HPET. The effect of this is that reading time stamps (from
kernel or user space) will be faster and more efficent.
Signed-off-by: davidwang <davidwang@zhaoxin.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: qiyuanwang@zhaoxin.com
Cc: linux-pm@vger.kernel.org
Cc: brucechang@via-alliance.com
Cc: cooperyan@zhaoxin.com
Cc: benjaminpan@viatech.com
Link: https://lkml.kernel.org/r/1516616057-5158-1-git-send-email-davidwang@zhaoxin.com
Commit 24c2503255 ("x86/microcode: Do not access the initrd after it has
been freed") fixed attempts to access initrd from the microcode loader
after it has been freed. However, a similar KASAN warning was reported
(stack trace edited):
smpboot: Booting Node 0 Processor 1 APIC 0x11
==================================================================
BUG: KASAN: use-after-free in find_cpio_data+0x9b5/0xa50
Read of size 1 at addr ffff880035ffd000 by task swapper/1/0
CPU: 1 PID: 0 Comm: swapper/1 Not tainted 4.14.8-slack #7
Hardware name: System manufacturer System Product Name/A88X-PLUS, BIOS 3003 03/10/2016
Call Trace:
dump_stack
print_address_description
kasan_report
? find_cpio_data
__asan_report_load1_noabort
find_cpio_data
find_microcode_in_initrd
__load_ucode_amd
load_ucode_amd_ap
load_ucode_ap
After some investigation, it turned out that a merge was done using the
wrong side to resolve, leading to picking up the previous state, before
the 24c2503255 fix. Therefore the Fixes tag below contains a merge
commit.
Revert the mismerge by catching the save_microcode_in_initrd_amd()
retval and thus letting the function exit with the last return statement
so that initrd_gone can be set to true.
Fixes: f26483eaed ("Merge branch 'x86/urgent' into x86/microcode, to resolve conflicts")
Reported-by: <higuita@gmx.net>
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Link: https://bugzilla.kernel.org/show_bug.cgi?id=198295
Link: https://lkml.kernel.org/r/20180123104133.918-2-bp@alien8.de
Commit b94b737331 ("x86/microcode/intel: Extend BDW late-loading with a
revision check") reduced the impact of erratum BDF90 for Broadwell model
79.
The impact can be reduced further by checking the size of the last level
cache portion per core.
Tony: "The erratum says the problem only occurs on the large-cache SKUs.
So we only need to avoid the update if we are on a big cache SKU that is
also running old microcode."
For more details, see erratum BDF90 in document #334165 (Intel Xeon
Processor E7-8800/4800 v4 Product Family Specification Update) from
September 2017.
Fixes: b94b737331 ("x86/microcode/intel: Extend BDW late-loading with a revision check")
Signed-off-by: Jia Zhang <zhang.jia@linux.alibaba.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Tony Luck <tony.luck@intel.com>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/1516321542-31161-1-git-send-email-zhang.jia@linux.alibaba.com
The function tracer can create a dynamically allocated trampoline that is
called by the function mcount or fentry hook that is used to call the
function callback that is registered. The problem is that the orc undwinder
will bail if it encounters one of these trampolines. This breaks the stack
trace of function callbacks, which include the stack tracer and setting the
stack trace for individual functions.
Since these dynamic trampolines are basically copies of the static ftrace
trampolines defined in ftrace_*.S, we do not need to create new orc entries
for the dynamic trampolines. Finding the return address on the stack will be
identical as the functions that were copied to create the dynamic
trampolines. When encountering a ftrace dynamic trampoline, we can just use
the orc entry of the ftrace static function that was copied for that
trampoline.
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Steven Rostedt discovered that the ftrace stack tracer is broken when
it's used with the ORC unwinder. The problem is that objtool is
instructed by the Makefile to ignore the ftrace_64.S code, so it doesn't
generate any ORC data for it.
Fix it by making the asm code objtool-friendly:
- Objtool doesn't like the fact that save_mcount_regs pushes RBP at the
beginning, but it's never restored (directly, at least). So just skip
the original RBP push, which is only needed for frame pointers anyway.
- Annotate some functions as normal callable functions with
ENTRY/ENDPROC.
- Add an empty unwind hint to return_to_handler(). The return address
isn't on the stack, so there's nothing ORC can do there. It will just
punt in the unlikely case it tries to unwind from that code.
With all that fixed, remove the OBJECT_FILES_NON_STANDARD Makefile
annotation so objtool can read the file.
Link: http://lkml.kernel.org/r/20180123040746.ih4ep3tk4pbjvg7c@treble
Reported-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Today 4 architectures set ARCH_SUPPORTS_MEMORY_FAILURE (arm64, parisc,
powerpc, and x86), while 4 other architectures set __ARCH_SI_TRAPNO
(alpha, metag, sparc, and tile). These two sets of architectures do
not interesect so remove the trapno paramater to remove confusion.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Pull x86 pti fixes from Thomas Gleixner:
"A small set of fixes for the meltdown/spectre mitigations:
- Make kprobes aware of retpolines to prevent probes in the retpoline
thunks.
- Make the machine check exception speculation protected. MCE used to
issue an indirect call directly from the ASM entry code. Convert
that to a direct call into a C-function and issue the indirect call
from there so the compiler can add the retpoline protection,
- Make the vmexit_fill_RSB() assembly less stupid
- Fix a typo in the PTI documentation"
* 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/retpoline: Optimize inline assembler for vmexit_fill_RSB
x86/pti: Document fix wrong index
kprobes/x86: Disable optimizing on the function jumps to indirect thunk
kprobes/x86: Blacklist indirect thunk functions for kprobes
retpoline: Introduce start/end markers of indirect thunk
x86/mce: Make machine check speculation protected
Limiting the scan width to the known last bus via the command line can
accelerate the boot noteworthy.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Jailhouse <jailhouse-dev@googlegroups.com>
Link: https://lkml.kernel.org/r/51f5fe62-ca8f-9286-5cdb-39df3fad78b4@siemens.com
Otherwise, Linux will not recognize precalibrated_tsc_khz and disable
the tsc as clocksource.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Jailhouse <jailhouse-dev@googlegroups.com>
Link: https://lkml.kernel.org/r/975fbfc9-2a64-cc56-40d5-164992ec3916@siemens.com
Since indirect jump instructions will be replaced by jump
to __x86_indirect_thunk_*, those jmp instruction must be
treated as an indirect jump. Since optprobe prohibits to
optimize probes in the function which uses an indirect jump,
it also needs to find out the function which jump to
__x86_indirect_thunk_* and disable optimization.
Add a check that the jump target address is between the
__indirect_thunk_start/end when optimizing kprobe.
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: David Woodhouse <dwmw@amazon.co.uk>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ananth N Mavinakayanahalli <ananth@linux.vnet.ibm.com>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Greg Kroah-Hartman <gregkh@linux-foundation.org>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/151629212062.10241.6991266100233002273.stgit@devbox
Introduce start/end markers of __x86_indirect_thunk_* functions.
To make it easy, consolidate .text.__x86.indirect_thunk.* sections
to one .text.__x86.indirect_thunk section and put it in the
end of kernel text section and adds __indirect_thunk_start/end
so that other subsystem (e.g. kprobes) can identify it.
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: David Woodhouse <dwmw@amazon.co.uk>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ananth N Mavinakayanahalli <ananth@linux.vnet.ibm.com>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Greg Kroah-Hartman <gregkh@linux-foundation.org>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/151629206178.10241.6828804696410044771.stgit@devbox
The machine check idtentry uses an indirect branch directly from the low
level code. This evades the speculation protection.
Replace it by a direct call into C code and issue the indirect call there
so the compiler can apply the proper speculation protection.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by:Borislav Petkov <bp@alien8.de>
Reviewed-by: David Woodhouse <dwmw@amazon.co.uk>
Niced-by: Peter Zijlstra <peterz@infradead.org>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/alpine.DEB.2.20.1801181626290.1847@nanos
Some issues have been reported with the for loop in stop_this_cpu() that
issues the 'wbinvd; hlt' sequence. Reverting this sequence to halt()
has been shown to resolve the issue.
However, the wbinvd is needed when running with SME. The reason for the
wbinvd is to prevent cache flush races between encrypted and non-encrypted
entries that have the same physical address. This can occur when
kexec'ing from memory encryption active to inactive or vice-versa. The
important thing is to not have outside of kernel text memory references
(such as stack usage), so the usage of the native_*() functions is needed
since these expand as inline asm sequences. So instead of reverting the
change, rework the sequence.
Move the wbinvd instruction outside of the for loop as native_wbinvd()
and make its execution conditional on X86_FEATURE_SME. In the for loop,
change the asm 'wbinvd; hlt' sequence back to a halt sequence but use
the native_halt() call.
Fixes: bba4ed011a ("x86/mm, kexec: Allow kexec to be used with SME")
Reported-by: Dave Young <dyoung@redhat.com>
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Dave Young <dyoung@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Yu Chen <yu.c.chen@intel.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: kexec@lists.infradead.org
Cc: ebiederm@redhat.com
Cc: Borislav Petkov <bp@alien8.de>
Cc: Rui Zhang <rui.zhang@intel.com>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20180117234141.21184.44067.stgit@tlendack-t1.amdoffice.net
L2 CDP can be controlled by kernel parameter "rdt=".
If "rdt=l2cdp", L2 CDP is turned on.
If "rdt=!l2cdp", L2 CDP is turned off.
Signed-off-by: Fenghua Yu <fenghua.yu@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: "Ravi V Shankar" <ravi.v.shankar@intel.com>
Cc: "Tony Luck" <tony.luck@intel.com>
Cc: Vikas" <vikas.shivappa@intel.com>
Cc: Sai Praneeth" <sai.praneeth.prakhya@intel.com>
Cc: Reinette" <reinette.chatre@intel.com>
Link: https://lkml.kernel.org/r/1513810644-78015-7-git-send-email-fenghua.yu@intel.com
Bit 0 in MSR IA32_L2_QOS_CFG (0xc82) is L2 CDP enable bit. By default,
the bit is zero, i.e. L2 CAT is enabled, and L2 CDP is disabled. When
the resctrl mount parameter "cdpl2" is given, the bit is set to 1 and L2
CDP is enabled.
In L2 CDP mode, the L2 CAT mask MSRs are re-mapped into interleaved pairs
of mask MSRs for code (referenced by an odd CLOSID) and data (referenced by
an even CLOSID).
Signed-off-by: Fenghua Yu <fenghua.yu@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: "Ravi V Shankar" <ravi.v.shankar@intel.com>
Cc: "Tony Luck" <tony.luck@intel.com>
Cc: Vikas" <vikas.shivappa@intel.com>
Cc: Sai Praneeth" <sai.praneeth.prakhya@intel.com>
Cc: Reinette" <reinette.chatre@intel.com>
Link: https://lkml.kernel.org/r/1513810644-78015-6-git-send-email-fenghua.yu@intel.com
L2 data and L2 code are added as new resources in rdt_resources_all[]
and data in the resources are configured.
When L2 CDP is enabled, the schemata will have the two resources in
this format:
L2DATA:l2id0=xxxx;l2id1=xxxx;....
L2CODE:l2id0=xxxx;l2id1=xxxx;....
xxxx represent CBM (Cache Bit Mask) values in the schemata, similar to all
others (L2 CAT/L3 CAT/L3 CDP).
Signed-off-by: Fenghua Yu <fenghua.yu@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: "Ravi V Shankar" <ravi.v.shankar@intel.com>
Cc: "Tony Luck" <tony.luck@intel.com>
Cc: Vikas" <vikas.shivappa@intel.com>
Cc: Sai Praneeth" <sai.praneeth.prakhya@intel.com>
Cc: Reinette" <reinette.chatre@intel.com>
Link: https://lkml.kernel.org/r/1513810644-78015-5-git-send-email-fenghua.yu@intel.com
* acpi-pm:
platform/x86: surfacepro3: Support for wakeup from suspend-to-idle
ACPI / PM: Use Low Power S0 Idle on more systems
ACPI / PM: Make it possible to ignore the system sleep blacklist
* pm-sleep:
PM / hibernate: Drop unused parameter of enough_swap
block, scsi: Fix race between SPI domain validation and system suspend
PM / sleep: Make lock/unlock_system_sleep() available to kernel modules
PM: hibernate: Do not subtract NR_FILE_MAPPED in minimum_image_size()
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BackMerge tag 'v4.15-rc8' into drm-next
Linux 4.15-rc8
Daniel requested this for so the intel CI won't fall over on drm-next
so often.
Pull x86 fixes from Ingo Molnar:
"Misc fixes:
- A rather involved set of memory hardware encryption fixes to
support the early loading of microcode files via the initrd. These
are larger than what we normally take at such a late -rc stage, but
there are two mitigating factors: 1) much of the changes are
limited to the SME code itself 2) being able to early load
microcode has increased importance in the post-Meltdown/Spectre
era.
- An IRQ vector allocator fix
- An Intel RDT driver use-after-free fix
- An APIC driver bug fix/revert to make certain older systems boot
again
- A pkeys ABI fix
- TSC calibration fixes
- A kdump fix"
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/apic/vector: Fix off by one in error path
x86/intel_rdt/cqm: Prevent use after free
x86/mm: Encrypt the initrd earlier for BSP microcode update
x86/mm: Prepare sme_encrypt_kernel() for PAGE aligned encryption
x86/mm: Centralize PMD flags in sme_encrypt_kernel()
x86/mm: Use a struct to reduce parameters for SME PGD mapping
x86/mm: Clean up register saving in the __enc_copy() assembly code
x86/idt: Mark IDT tables __initconst
Revert "x86/apic: Remove init_bsp_APIC()"
x86/mm/pkeys: Fix fill_sig_info_pkey
x86/tsc: Print tsc_khz, when it differs from cpu_khz
x86/tsc: Fix erroneous TSC rate on Skylake Xeon
x86/tsc: Future-proof native_calibrate_tsc()
kdump: Write the correct address of mem_section into vmcoreinfo
Pull x86 pti bits and fixes from Thomas Gleixner:
"This last update contains:
- An objtool fix to prevent a segfault with the gold linker by
changing the invocation order. That's not just for gold, it's a
general robustness improvement.
- An improved error message for objtool which spares tearing hairs.
- Make KASAN fail loudly if there is not enough memory instead of
oopsing at some random place later
- RSB fill on context switch to prevent RSB underflow and speculation
through other units.
- Make the retpoline/RSB functionality work reliably for both Intel
and AMD
- Add retpoline to the module version magic so mismatch can be
detected
- A small (non-fix) update for cpufeatures which prevents cpu feature
clashing for the upcoming extra mitigation bits to ease
backporting"
* 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
module: Add retpoline tag to VERMAGIC
x86/cpufeature: Move processor tracing out of scattered features
objtool: Improve error message for bad file argument
objtool: Fix seg fault with gold linker
x86/retpoline: Add LFENCE to the retpoline/RSB filling RSB macros
x86/retpoline: Fill RSB on context switch for affected CPUs
x86/kasan: Panic if there is not enough memory to boot
Keith reported the following warning:
WARNING: CPU: 28 PID: 1420 at kernel/irq/matrix.c:222 irq_matrix_remove_managed+0x10f/0x120
x86_vector_free_irqs+0xa1/0x180
x86_vector_alloc_irqs+0x1e4/0x3a0
msi_domain_alloc+0x62/0x130
The reason for this is that if the vector allocation fails the error
handling code tries to free the failed vector as well, which causes the
above imbalance warning to trigger.
Adjust the error path to handle this correctly.
Fixes: b5dc8e6c21 ("x86/irq: Use hierarchical irqdomain to manage CPU interrupt vectors")
Reported-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Keith Busch <keith.busch@intel.com>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/alpine.DEB.2.20.1801161217300.1823@nanos
intel_rdt_iffline_cpu() -> domain_remove_cpu() frees memory first and then
proceeds accessing it.
BUG: KASAN: use-after-free in find_first_bit+0x1f/0x80
Read of size 8 at addr ffff883ff7c1e780 by task cpuhp/31/195
find_first_bit+0x1f/0x80
has_busy_rmid+0x47/0x70
intel_rdt_offline_cpu+0x4b4/0x510
Freed by task 195:
kfree+0x94/0x1a0
intel_rdt_offline_cpu+0x17d/0x510
Do the teardown first and then free memory.
Fixes: 24247aeeab ("x86/intel_rdt/cqm: Improve limbo list processing")
Reported-by: Joseph Salisbury <joseph.salisbury@canonical.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Ravi Shankar <ravi.v.shankar@intel.com>
Cc: Peter Zilstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Vikas Shivappa <vikas.shivappa@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: "Roderick W. Smith" <rod.smith@canonical.com>
Cc: 1733662@bugs.launchpad.net
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/alpine.DEB.2.20.1801161957510.2366@nanos
Processor tracing is already enumerated in word 9 (CPUID[7,0].EBX),
so do not duplicate it in the scattered features word.
Besides being more tidy, this will be useful for KVM when it presents
processor tracing to the guests. KVM selects host features that are
supported by both the host kernel (depending on command line options,
CPU errata, or whatever) and KVM. Whenever a full feature word exists,
KVM's code is written in the expectation that the CPUID bit number
matches the X86_FEATURE_* bit number, but this is not the case for
X86_FEATURE_INTEL_PT.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Luwei Kang <luwei.kang@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: kvm@vger.kernel.org
Link: http://lkml.kernel.org/r/1516117345-34561-1-git-send-email-pbonzini@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This part of Secure Encrypted Virtualization (SEV) patch series focuses on KVM
changes required to create and manage SEV guests.
SEV is an extension to the AMD-V architecture which supports running encrypted
virtual machine (VMs) under the control of a hypervisor. Encrypted VMs have their
pages (code and data) secured such that only the guest itself has access to
unencrypted version. Each encrypted VM is associated with a unique encryption key;
if its data is accessed to a different entity using a different key the encrypted
guest's data will be incorrectly decrypted, leading to unintelligible data.
This security model ensures that hypervisor will no longer able to inspect or
alter any guest code or data.
The key management of this feature is handled by a separate processor known as
the AMD Secure Processor (AMD-SP) which is present on AMD SOCs. The SEV Key
Management Specification (see below) provides a set of commands which can be
used by hypervisor to load virtual machine keys through the AMD-SP driver.
The patch series adds a new ioctl in KVM driver (KVM_MEMORY_ENCRYPT_OP). The
ioctl will be used by qemu to issue SEV guest-specific commands defined in Key
Management Specification.
The following links provide additional details:
AMD Memory Encryption white paper:
http://amd-dev.wpengine.netdna-cdn.com/wordpress/media/2013/12/AMD_Memory_Encryption_Whitepaper_v7-Public.pdf
AMD64 Architecture Programmer's Manual:
http://support.amd.com/TechDocs/24593.pdf
SME is section 7.10
SEV is section 15.34
SEV Key Management:
http://support.amd.com/TechDocs/55766_SEV-KM API_Specification.pdf
KVM Forum Presentation:
http://www.linux-kvm.org/images/7/74/02x08A-Thomas_Lendacky-AMDs_Virtualizatoin_Memory_Encryption_Technology.pdf
SEV Guest BIOS support:
SEV support has been add to EDKII/OVMF BIOS
https://github.com/tianocore/edk2
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Remote TLB flush does a busy wait which is fine in bare-metal
scenario. But with-in the guest, the vcpus might have been pre-empted or
blocked. In this scenario, the initator vcpu would end up busy-waiting
for a long amount of time; it also consumes CPU unnecessarily to wake
up the target of the shootdown.
This patch set adds support for KVM's new paravirtualized TLB flush;
remote TLB flush does not wait for vcpus that are sleeping, instead
KVM will flush the TLB as soon as the vCPU starts running again.
The improvement is clearly visible when the host is overcommitted; in this
case, the PV TLB flush (in addition to avoiding the wait on the main CPU)
prevents preempted vCPUs from stealing precious execution time from the
running ones.
Testing on a Xeon Gold 6142 2.6GHz 2 sockets, 32 cores, 64 threads,
so 64 pCPUs, and each VM is 64 vCPUs.
ebizzy -M
vanilla optimized boost
1VM 46799 48670 4%
2VM 23962 42691 78%
3VM 16152 37539 132%
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Wanpeng Li <wanpeng.li@hotmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
The next patch will add another bit to the preempted field in
kvm_steal_time. Define a constant for bit 0 (the only one that is
currently used).
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Wanpeng Li <wanpeng.li@hotmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Along with the fixes in UV4A (rev2) MMRs, the code to access those
MMRs also was modified by the fixes. UV3, UV4, and UV4A no longer
have compatible setups for Global Address Memory (GAM).
Correct the new mistakes.
Signed-off-by: Mike Travis <mike.travis@hpe.com>
Acked-by: Andrew Banman <abanman@hpe.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Dimitri Sivanich <sivanich@hpe.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Russ Anderson <rja@hpe.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1515440405-20880-6-git-send-email-mike.travis@hpe.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Upcoming Intel CascadeLake and IceLake processors have some architecture
changes that required fixes in the UV4 HUB bringing that chip to
revision 2. The nomenclature for that new chip is "UV4A".
This patch fixes the references for the expanded MMR definitions in the
previous (automated) patch.
Signed-off-by: Mike Travis <mike.travis@hpe.com>
Acked-by: Andrew Banman <abanman@hpe.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Dimitri Sivanich <sivanich@hpe.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Russ Anderson <rja@hpe.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1515440405-20880-3-git-send-email-mike.travis@hpe.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Among the existing architecture specific versions of
copy_siginfo_to_user32 there are several different implementation
problems. Some architectures fail to handle all of the cases in in
the siginfo union. Some architectures perform a blind copy of the
siginfo union when the si_code is negative. A blind copy suggests the
data is expected to be in 32bit siginfo format, which means that
receiving such a signal via signalfd won't work, or that the data is
in 64bit siginfo and the code is copying nonsense to userspace.
Create a single instance of copy_siginfo_to_user32 that all of the
architectures can share, and teach it to handle all of the cases in
the siginfo union correctly, with the assumption that siginfo is
stored internally to the kernel is 64bit siginfo format.
A special case is made for x86 x32 format. This is needed as presence
of both x32 and ia32 on x86_64 results in two different 32bit signal
formats. By allowing this small special case there winds up being
exactly one code base that needs to be maintained between all of the
architectures. Vastly increasing the testing base and the chances of
finding bugs.
As the x86 copy of copy_siginfo_to_user32 the call of the x86
signal_compat_build_tests were moved into sigaction_compat_abi, so
that they will keep running.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Currently the BSP microcode update code examines the initrd very early
in the boot process. If SME is active, the initrd is treated as being
encrypted but it has not been encrypted (in place) yet. Update the
early boot code that encrypts the kernel to also encrypt the initrd so
that early BSP microcode updates work.
Tested-by: Gabriel Craciunescu <nix.or.die@gmail.com>
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Reviewed-by: Borislav Petkov <bp@suse.de>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brijesh Singh <brijesh.singh@amd.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/20180110192634.6026.10452.stgit@tlendack-t1.amdoffice.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The function copy_siginfo_from_user32 is used for two things, in ptrace
since the dawn of siginfo for arbirarily modifying a signal that
user space sees, and in sigqueueinfo to send a signal with arbirary
siginfo data.
Create a single copy of copy_siginfo_from_user32 that all architectures
share, and teach it to handle all of the cases in the siginfo union.
In the generic version of copy_siginfo_from_user32 ensure that all
of the fields in siginfo are initialized so that the siginfo structure
can be safely copied to userspace if necessary.
When copying the embedded sigval union copy the si_int member. That
ensures the 32bit values passes through the kernel unchanged.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Having si_codes in many different files simply encourages duplicate
definitions that can cause problems later. To avoid that merge the
ia64 specific si_codes into uapi/asm-generic/siginfo.h
Update the sanity checks in arch/x86/kernel/signal_compat.c to expect
the now lager NSIGILL and NSIGFPE. As nothing excpe the larger count
is exposed on x86 no additional code needs to be updated.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
--EWB Added #ifdef CONFIG_X86_X32_ABI to arch/x86/kernel/signal_compat.c
Changed #ifdef CONFIG_X86_X32 to #ifdef CONFIG_X86_X32_ABI in
linux/compat.h
CONFIG_X86_X32 is set when the user requests X32 support.
CONFIG_X86_X32_ABI is set when the user requests X32 support
and the tool-chain has X32 allowing X32 support to be built.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
x2apic_phys is not available when CONFIG_X86_X2APIC=n and the code is not
optimized out resulting in a build fail:
jailhouse.c: In function ‘jailhouse_get_smp_config’:
jailhouse.c:73:3: error: ‘x2apic_phys’ undeclared (first use in this function)
Fixes: 11c8dc419b ("x86/jailhouse: Enable APIC and SMP support")
Reported-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Jan Kiszka <jan.kiszka@siemens.com>
Cc: jailhouse-dev@googlegroups.com
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
We'll need that name for a generic implementation soon.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
To implement the x86 forbid_dac and iommu_sac_force we want an arch hook
so that it can apply the global options across all dma_map_ops
implementations.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Lift the code from x86 so that we behave consistently. In the future we
should probably warn if any of these is set.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Jesper Nilsson <jesper.nilsson@axis.com>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> [m68k]
On context switch from a shallow call stack to a deeper one, as the CPU
does 'ret' up the deeper side it may encounter RSB entries (predictions for
where the 'ret' goes to) which were populated in userspace.
This is problematic if neither SMEP nor KPTI (the latter of which marks
userspace pages as NX for the kernel) are active, as malicious code in
userspace may then be executed speculatively.
Overwrite the CPU's return prediction stack with calls which are predicted
to return to an infinite loop, to "capture" speculation if this
happens. This is required both for retpoline, and also in conjunction with
IBRS for !SMEP && !KPTI.
On Skylake+ the problem is slightly different, and an *underflow* of the
RSB may cause errant branch predictions to occur. So there it's not so much
overwrite, as *filling* the RSB to attempt to prevent it getting
empty. This is only a partial solution for Skylake+ since there are many
other conditions which may result in the RSB becoming empty. The full
solution on Skylake+ is to use IBRS, which will prevent the problem even
when the RSB becomes empty. With IBRS, the RSB-stuffing will not be
required on context switch.
[ tglx: Added missing vendor check and slighty massaged comments and
changelog ]
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Arjan van de Ven <arjan@linux.intel.com>
Cc: gnomes@lxorguk.ukuu.org.uk
Cc: Rik van Riel <riel@redhat.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: thomas.lendacky@amd.com
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Jiri Kosina <jikos@kernel.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Kees Cook <keescook@google.com>
Cc: Tim Chen <tim.c.chen@linux.intel.com>
Cc: Greg Kroah-Hartman <gregkh@linux-foundation.org>
Cc: Paul Turner <pjt@google.com>
Link: https://lkml.kernel.org/r/1515779365-9032-1-git-send-email-dwmw@amazon.co.uk
The typical I/O interrupts in non-root cells are MSI-based. However, the
platform UARTs do not support MSI. In order to run a non-root cell that
shall use one of them, the standard IOAPIC must be registered and 1:1
routing for IRQ 3 and 4 set up.
If an IOAPIC is not available, the boot loader clears standard_ioapic in
the setup data, so registration is skipped. If the guest is not allowed to
to use one of those pins, Jailhouse will simply ignore the access.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: jailhouse-dev@googlegroups.com
Link: https://lkml.kernel.org/r/90d942dda9d48a8046e00bb3c1bb6757c83227be.1511770314.git.jan.kiszka@siemens.com
