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Author SHA1 Message Date
Linus Torvalds
80a76c60e5 Updates for timekeeping and PTP core:
The cross-timestamp mechanism which allows to correlate hardware
   clocks uses clocksource pointers for describing the correlation.
 
   That's suboptimal as drivers need to obtain the pointer, which requires
   needless exports and exposing internals.
 
   This can be completely avoided by assigning clocksource IDs and using
   them for describing the correlated clock source.
 
   This update adds clocksource IDs to all clocksources in the tree which
   can be exposed to this mechanism and removes the pointer and now needless
   exports.
 
   This is separate from the timer core changes as it was provided to the
   PTP folks to build further changes on top.
 
   A related improvement for the core and the correlation handling has not
   made it this time, but is expected to get ready for the next round.
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Merge tag 'timers-ptp-2024-03-10' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull clocksource updates from Thomas Gleixner:
 "Updates for timekeeping and PTP core.

  The cross-timestamp mechanism which allows to correlate hardware
  clocks uses clocksource pointers for describing the correlation.

  That's suboptimal as drivers need to obtain the pointer, which
  requires needless exports and exposing internals. This can all be
  completely avoided by assigning clocksource IDs and using them for
  describing the correlated clock source.

  So this adds clocksource IDs to all clocksources in the tree which can
  be exposed to this mechanism and removes the pointer and now needless
  exports.

  A related improvement for the core and the correlation handling has
  not made it this time, but is expected to get ready for the next
  round"

* tag 'timers-ptp-2024-03-10' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  kvmclock: Unexport kvmclock clocksource
  treewide: Remove system_counterval_t.cs, which is never read
  timekeeping: Evaluate system_counterval_t.cs_id instead of .cs
  ptp/kvm, arm_arch_timer: Set system_counterval_t.cs_id to constant
  x86/kvm, ptp/kvm: Add clocksource ID, set system_counterval_t.cs_id
  x86/tsc: Add clocksource ID, set system_counterval_t.cs_id
  timekeeping: Add clocksource ID to struct system_counterval_t
  x86/tsc: Correct kernel-doc notation
2024-03-11 14:25:18 -07:00
Linus Torvalds
4527e83780 Updates for the MSI interrupt subsystem and RISC-V initial MSI support:
- Core and platform-MSI
 
     The core changes have been adopted from previous work which converted
     ARM[64] to the new per device MSI domain model, which was merged to
     support multiple MSI domain per device. The ARM[64] changes are being
     worked on too, but have not been ready yet. The core and platform-MSI
     changes have been split out to not hold up RISC-V and to avoid that
     RISC-V builds on the scheduled for removal interfaces.
 
     The core support provides new interfaces to handle wire to MSI bridges
     in a straight forward way and introduces new platform-MSI interfaces
     which are built on top of the per device MSI domain model.
 
     Once ARM[64] is converted over the old platform-MSI interfaces and the
     related ugliness in the MSI core code will be removed.
 
   - Drivers:
 
     - Add a new driver for the Andes hart-level interrupt controller
 
     - Rework the SiFive PLIC driver to prepare for MSI suport
 
     - Expand the RISC-V INTC driver to support the new RISC-V AIA
       controller which provides the basis for MSI on RISC-V
 
     - A few fixup for the fallout of the core changes.
 
     The actual MSI parts for RISC-V were finalized late and have been
     post-poned for the next merge window.
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Merge tag 'irq-msi-2024-03-10' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull MSI updates from Thomas Gleixner:
 "Updates for the MSI interrupt subsystem and initial RISC-V MSI
  support.

  The core changes have been adopted from previous work which converted
  ARM[64] to the new per device MSI domain model, which was merged to
  support multiple MSI domain per device. The ARM[64] changes are being
  worked on too, but have not been ready yet. The core and platform-MSI
  changes have been split out to not hold up RISC-V and to avoid that
  RISC-V builds on the scheduled for removal interfaces.

  The core support provides new interfaces to handle wire to MSI bridges
  in a straight forward way and introduces new platform-MSI interfaces
  which are built on top of the per device MSI domain model.

  Once ARM[64] is converted over the old platform-MSI interfaces and the
  related ugliness in the MSI core code will be removed.

  The actual MSI parts for RISC-V were finalized late and have been
  post-poned for the next merge window.

  Drivers:

   - Add a new driver for the Andes hart-level interrupt controller

   - Rework the SiFive PLIC driver to prepare for MSI suport

   - Expand the RISC-V INTC driver to support the new RISC-V AIA
     controller which provides the basis for MSI on RISC-V

   - A few fixup for the fallout of the core changes"

* tag 'irq-msi-2024-03-10' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (29 commits)
  irqchip/riscv-intc: Fix low-level interrupt handler setup for AIA
  x86/apic/msi: Use DOMAIN_BUS_GENERIC_MSI for HPET/IO-APIC domain search
  genirq/matrix: Dynamic bitmap allocation
  irqchip/riscv-intc: Add support for RISC-V AIA
  irqchip/sifive-plic: Improve locking safety by using irqsave/irqrestore
  irqchip/sifive-plic: Parse number of interrupts and contexts early in plic_probe()
  irqchip/sifive-plic: Cleanup PLIC contexts upon irqdomain creation failure
  irqchip/sifive-plic: Use riscv_get_intc_hwnode() to get parent fwnode
  irqchip/sifive-plic: Use devm_xyz() for managed allocation
  irqchip/sifive-plic: Use dev_xyz() in-place of pr_xyz()
  irqchip/sifive-plic: Convert PLIC driver into a platform driver
  irqchip/riscv-intc: Introduce Andes hart-level interrupt controller
  irqchip/riscv-intc: Allow large non-standard interrupt number
  genirq/irqdomain: Don't call ops->select for DOMAIN_BUS_ANY tokens
  irqchip/imx-intmux: Handle pure domain searches correctly
  genirq/msi: Provide MSI_FLAG_PARENT_PM_DEV
  genirq/irqdomain: Reroute device MSI create_mapping
  genirq/msi: Provide allocation/free functions for "wired" MSI interrupts
  genirq/msi: Optionally use dev->fwnode for device domain
  genirq/msi: Provide DOMAIN_BUS_WIRED_TO_MSI
  ...
2024-03-11 14:03:03 -07:00
Pawan Gupta
8076fcde01 x86/rfds: Mitigate Register File Data Sampling (RFDS)
RFDS is a CPU vulnerability that may allow userspace to infer kernel
stale data previously used in floating point registers, vector registers
and integer registers. RFDS only affects certain Intel Atom processors.

Intel released a microcode update that uses VERW instruction to clear
the affected CPU buffers. Unlike MDS, none of the affected cores support
SMT.

Add RFDS bug infrastructure and enable the VERW based mitigation by
default, that clears the affected buffers just before exiting to
userspace. Also add sysfs reporting and cmdline parameter
"reg_file_data_sampling" to control the mitigation.

For details see:
Documentation/admin-guide/hw-vuln/reg-file-data-sampling.rst

Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Josh Poimboeuf <jpoimboe@kernel.org>
2024-03-11 13:13:48 -07:00
Pawan Gupta
e95df4ec0c x86/mmio: Disable KVM mitigation when X86_FEATURE_CLEAR_CPU_BUF is set
Currently MMIO Stale Data mitigation for CPUs not affected by MDS/TAA is
to only deploy VERW at VMentry by enabling mmio_stale_data_clear static
branch. No mitigation is needed for kernel->user transitions. If such
CPUs are also affected by RFDS, its mitigation may set
X86_FEATURE_CLEAR_CPU_BUF to deploy VERW at kernel->user and VMentry.
This could result in duplicate VERW at VMentry.

Fix this by disabling mmio_stale_data_clear static branch when
X86_FEATURE_CLEAR_CPU_BUF is enabled.

Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: Dave Hansen <dave.hansen@linux.intel.com>
2024-03-11 13:13:28 -07:00
Paolo Bonzini
b00471a552 KVM VMX changes for 6.9:
- Fix a bug where KVM would report stale/bogus exit qualification information
    when exiting to userspace due to an unexpected VM-Exit while the CPU was
    vectoring an exception.
 
  - Add a VMX flag in /proc/cpuinfo to report 5-level EPT support.
 
  - Clean up the logic for massaging the passthrough MSR bitmaps when userspace
    changes its MSR filter.
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Merge tag 'kvm-x86-vmx-6.9' of https://github.com/kvm-x86/linux into HEAD

KVM VMX changes for 6.9:

 - Fix a bug where KVM would report stale/bogus exit qualification information
   when exiting to userspace due to an unexpected VM-Exit while the CPU was
   vectoring an exception.

 - Add a VMX flag in /proc/cpuinfo to report 5-level EPT support.

 - Clean up the logic for massaging the passthrough MSR bitmaps when userspace
   changes its MSR filter.
2024-03-11 10:31:29 -04:00
Paolo Bonzini
233d0bc4d8 LoongArch KVM changes for v6.9
1. Set reserved bits as zero in CPUCFG.
 2. Start SW timer only when vcpu is blocking.
 3. Do not restart SW timer when it is expired.
 4. Remove unnecessary CSR register saving during enter guest.
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Merge tag 'loongarch-kvm-6.9' of git://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson into HEAD

LoongArch KVM changes for v6.9

* Set reserved bits as zero in CPUCFG.
* Start SW timer only when vcpu is blocking.
* Do not restart SW timer when it is expired.
* Remove unnecessary CSR register saving during enter guest.
2024-03-11 09:56:54 -04:00
Paolo Bonzini
7d8942d8e7 KVM GUEST_MEMFD fixes for 6.8:
- Make KVM_MEM_GUEST_MEMFD mutually exclusive with KVM_MEM_READONLY to
    avoid creating ABI that KVM can't sanely support.
 
  - Update documentation for KVM_SW_PROTECTED_VM to make it abundantly
    clear that such VMs are purely a development and testing vehicle, and
    come with zero guarantees.
 
  - Limit KVM_SW_PROTECTED_VM guests to the TDP MMU, as the long term plan
    is to support confidential VMs with deterministic private memory (SNP
    and TDX) only in the TDP MMU.
 
  - Fix a bug in a GUEST_MEMFD negative test that resulted in false passes
    when verifying that KVM_MEM_GUEST_MEMFD memslots can't be dirty logged.
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Merge tag 'kvm-x86-guest_memfd_fixes-6.8' of https://github.com/kvm-x86/linux into HEAD

KVM GUEST_MEMFD fixes for 6.8:

 - Make KVM_MEM_GUEST_MEMFD mutually exclusive with KVM_MEM_READONLY to
   avoid creating ABI that KVM can't sanely support.

 - Update documentation for KVM_SW_PROTECTED_VM to make it abundantly
   clear that such VMs are purely a development and testing vehicle, and
   come with zero guarantees.

 - Limit KVM_SW_PROTECTED_VM guests to the TDP MMU, as the long term plan
   is to support confidential VMs with deterministic private memory (SNP
   and TDX) only in the TDP MMU.

 - Fix a bug in a GUEST_MEMFD negative test that resulted in false passes
   when verifying that KVM_MEM_GUEST_MEMFD memslots can't be dirty logged.
2024-03-09 11:48:35 -05:00
Stephen Boyd
40f18dbbb4 x86/of: Unconditionally call unflatten_and_copy_device_tree()
Call this function unconditionally so that we can populate an empty DTB
on platforms that don't boot with a firmware provided or builtin DTB.
There's no harm in calling unflatten_device_tree() unconditionally here.
If there isn't a non-NULL 'initial_boot_params' pointer then
unflatten_device_tree() returns early.

Cc: Rob Herring <robh+dt@kernel.org>
Cc: Frank Rowand <frowand.list@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: x86@kernel.org
Cc: H. Peter Anvin <hpa@zytor.com>
Tested-by: Saurabh Sengar <ssengar@linux.microsoft.com>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
Link: https://lore.kernel.org/r/20240217010557.2381548-5-sboyd@kernel.org
Signed-off-by: Rob Herring <robh@kernel.org>
2024-03-08 12:50:39 -06:00
Changbin Du
c0935fca6b x86/sev: Disable KMSAN for memory encryption TUs
Instrumenting sev.c and mem_encrypt_identity.c with KMSAN will result in
a triple-faulting kernel. Some of the code is invoked too early during
boot, before KMSAN is ready.

Disable KMSAN instrumentation for the two translation units.

  [ bp: Massage commit message. ]

Signed-off-by: Changbin Du <changbin.du@huawei.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Link: https://lore.kernel.org/r/20240308044401.1120395-1-changbin.du@huawei.com
2024-03-08 08:59:22 +01:00
Xin Li (Intel)
c416b5bac6 x86/fred: Fix init_task thread stack pointer initialization
As TOP_OF_KERNEL_STACK_PADDING was defined as 0 on x86_64, it went
unnoticed that the initialization of the .sp field in INIT_THREAD and some
calculations in the low level startup code do not take the padding into
account.

FRED enabled kernels require a 16 byte padding, which means that the init
task initialization and the low level startup code use the wrong stack
offset.

Subtract TOP_OF_KERNEL_STACK_PADDING in all affected places to adjust for
this.

Fixes: 65c9cc9e2c ("x86/fred: Reserve space for the FRED stack frame")
Fixes: 3adee777ad ("x86/smpboot: Remove initial_stack on 64-bit")
Reported-by: kernel test robot <oliver.sang@intel.com>
Signed-off-by: Xin Li (Intel) <xin@zytor.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Closes: https://lore.kernel.org/oe-lkp/202402262159.183c2a37-lkp@intel.com
Link: https://lore.kernel.org/r/20240304083333.449322-1-xin@zytor.com
2024-03-07 11:55:36 +01:00
Jinghao Jia
290eb13f1a x86/kprobes: Boost more instructions from grp2/3/4/5
With the instruction decoder, we are now able to decode and recognize
instructions with opcode extensions. There are more instructions in
these groups that can be boosted:

Group 2: ROL, ROR, RCL, RCR, SHL/SAL, SHR, SAR
Group 3: TEST, NOT, NEG, MUL, IMUL, DIV, IDIV
Group 4: INC, DEC (byte operation)
Group 5: INC, DEC (word/doubleword/quadword operation)

These instructions are not boosted previously because there are reserved
opcodes within the groups, e.g., group 2 with ModR/M.nnn == 110 is
unmapped. As a result, kprobes attached to them requires two int3 traps
as being non-boostable also prevents jump-optimization.

Some simple tests on QEMU show that after boosting and jump-optimization
a single kprobe on these instructions with an empty pre-handler runs 10x
faster (~1000 cycles vs. ~100 cycles).

Since these instructions are mostly ALU operations and do not touch
special registers like RIP, let's boost them so that we get the
performance benefit.

Link: https://lore.kernel.org/all/20240204031300.830475-4-jinghao7@illinois.edu/

Signed-off-by: Jinghao Jia <jinghao7@illinois.edu>
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2024-03-07 00:26:01 +09:00
Jinghao Jia
e884edbb84 x86/kprobes: Prohibit kprobing on INT and UD
Both INT (INT n, INT1, INT3, INTO) and UD (UD0, UD1, UD2) serve special
purposes in the kernel, e.g., INT3 is used by KGDB and UD2 is involved
in LLVM-KCFI instrumentation. At the same time, attaching kprobes on
these instructions (particularly UD) will pollute the stack trace dumped
in the kernel ring buffer, since the exception is triggered in the copy
buffer rather than the original location.

Check for INT and UD in can_probe and reject any kprobes trying to
attach to these instructions.

Link: https://lore.kernel.org/all/20240204031300.830475-3-jinghao7@illinois.edu/

Suggested-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Jinghao Jia <jinghao7@illinois.edu>
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2024-03-07 00:26:01 +09:00
Jinghao Jia
e4778a0ef3 x86/kprobes: Refactor can_{probe,boost} return type to bool
Both can_probe and can_boost have int return type but are using int as
boolean in their context.

Refactor both functions to make them actually return boolean.

Link: https://lore.kernel.org/all/20240204031300.830475-2-jinghao7@illinois.edu/

Signed-off-by: Jinghao Jia <jinghao7@illinois.edu>
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2024-03-07 00:26:01 +09:00
Thomas Gleixner
f0551af021 x86/topology: Ignore non-present APIC IDs in a present package
Borislav reported that one of his systems has a broken MADT table which
advertises eight present APICs and 24 non-present APICs in the same
package.

The non-present ones are considered hot-pluggable by the topology
evaluation code, which is obviously bogus as there is no way to hot-plug
within the same package.

As the topology evaluation code accounts for hot-pluggable CPUs in a
package, the maximum number of cores per package is computed wrong, which
in turn causes the uncore performance counter driver to access non-existing
MSRs. It will probably confuse other entities which rely on the maximum
number of cores and threads per package too.

Cure this by ignoring hot-pluggable APIC IDs within a present package.

In theory it would be reasonable to just do this unconditionally, but then
there is this thing called reality^Wvirtualization which ruins
everything. Virtualization is the only existing user of "physical" hotplug
and the virtualization tools allow the above scenario. Whether that is
actually in use or not is unknown.

As it can be argued that the virtualization case is not affected by the
issues which exposed the reported problem, allow the bogosity if the kernel
determined that it is running in a VM for now.

Fixes: 89b0f15f40 ("x86/cpu/topology: Get rid of cpuinfo::x86_max_cores")
Reported-by: Borislav Petkov (AMD) <bp@alien8.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Borislav Petkov (AMD) <bp@alien8.de>
Link: https://lore.kernel.org/r/87a5nbvccx.ffs@tglx
2024-03-06 14:35:30 +01:00
He Rongguang
6b8e288f49 cpuidle: ACPI/intel: fix MWAIT hint target C-state computation
According to x86 spec ([1] and [2]), MWAIT hint_address[7:4] plus 1 is
the corresponding C-state, and 0xF means C0.

ACPI C-state table usually only contains C1+, but nothing prevents ACPI
firmware from presenting a C-state (maybe C1+) but using MWAIT address C0
(i.e., 0xF in ACPI FFH MWAIT hint address). And if this is the case, Linux
erroneously treat this cstate as C16, while actually this should be valid
C0 instead of C16, as per the specifications.

Since ACPI firmware is out of Linux kernel scope, fix the kernel handling
of 0xF ->(to) C0 in this situation. This is found when a tweaked ACPI
C-state table is presented by Qemu to VM.

Also modify the intel_idle case for code consistency.

[1]. Intel SDM Vol 2, Table 4-11. MWAIT Hints
Register (EAX): "Value of 0 means C1; 1 means C2 and so on
Value of 01111B means C0".

[2]. AMD manual Vol 3, MWAIT: "The processor C-state is EAX[7:4]+1, so to
request C0 is to place the value F in EAX[7:4] and to request C1 is to
place the value 0 in EAX[7:4].".

Signed-off-by: He Rongguang <herongguang@linux.alibaba.com>
[ rjw: Subject and changelog edits, whitespace fixups ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2024-03-05 21:25:18 +01:00
Perry Yuan
a51ab63b29 ACPI: CPPC: enable AMD CPPC V2 support for family 17h processors
As there are some AMD processors which only support CPPC V2 firmware and
BIOS implementation, the amd_pstate driver will be failed to load when
system booting with below kernel warning message:

[    0.477523] amd_pstate: the _CPC object is not present in SBIOS or ACPI disabled

To make the amd_pstate driver can be loaded on those TR40 processors, it
needs to match x86_model from 0x30 to 0x7F for family 17H.
With the change, the system can load amd_pstate driver as expected.

Reviewed-by: Mario Limonciello <mario.limonciello@amd.com>
Reported-by: Gino Badouri <badouri.g@gmail.com>
Closes: https://bugzilla.kernel.org/show_bug.cgi?id=218171
Fixes: fbd74d1689 ("ACPI: CPPC: Fix enabling CPPC on AMD systems with shared memory")
Signed-off-by: Perry Yuan <perry.yuan@amd.com>
Reviewed-by: Gautham R. Shenoy <gautham.shenoy@amd.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2024-03-05 13:23:12 +01:00
Ard Biesheuvel
428080c9b1 x86/sev: Move early startup code into .head.text section
In preparation for implementing rigorous build time checks to enforce
that only code that can support it will be called from the early 1:1
mapping of memory, move SEV init code that is called in this manner to
the .head.text section.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Tested-by: Tom Lendacky <thomas.lendacky@amd.com>
Link: https://lore.kernel.org/r/20240227151907.387873-19-ardb+git@google.com
2024-03-04 18:12:37 +01:00
Ard Biesheuvel
8282639576 x86/startup_64: Simplify virtual switch on primary boot
The secondary startup code is used on the primary boot path as well, but
in this case, the initial part runs from a 1:1 mapping, until an
explicit cross-jump is made to the kernel virtual mapping of the same
code.

On the secondary boot path, this jump is pointless as the code already
executes from the mapping targeted by the jump. So combine this
cross-jump with the jump from startup_64() into the common boot path.
This simplifies the execution flow, and clearly separates code that runs
from a 1:1 mapping from code that runs from the kernel virtual mapping.

Note that this requires a page table switch, so hoist the CR3 assignment
into startup_64() as well. And since absolute symbol references will no
longer be permitted in .head.text once we enable the associated build
time checks, a RIP-relative memory operand is used in the JMP
instruction, referring to an absolute constant in the .init.rodata
section.

Given that the secondary startup code does not require a special
placement inside the executable, move it to the .text section.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Tested-by: Tom Lendacky <thomas.lendacky@amd.com>
Link: https://lore.kernel.org/r/20240227151907.387873-15-ardb+git@google.com
2024-03-04 18:12:20 +01:00
Ard Biesheuvel
d6a41f184d x86/startup_64: Simplify calculation of initial page table address
Determining the address of the initial page table to program into CR3
involves:
- taking the physical address
- adding the SME encryption mask

On the primary entry path, the code is mapped using a 1:1 virtual to
physical translation, so the physical address can be taken directly
using a RIP-relative LEA instruction.

On the secondary entry path, the address can be obtained by taking the
offset from the virtual kernel base (__START_kernel_map) and adding the
physical kernel base.

This is implemented in a slightly confusing way, so clean this up.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Tested-by: Tom Lendacky <thomas.lendacky@amd.com>
Link: https://lore.kernel.org/r/20240227151907.387873-14-ardb+git@google.com
2024-03-04 18:12:16 +01:00
Ard Biesheuvel
63bed96604 x86/startup_64: Defer assignment of 5-level paging global variables
Assigning the 5-level paging related global variables from the earliest
C code using explicit references that use the 1:1 translation of memory
is unnecessary, as the startup code itself does not rely on them to
create the initial page tables, and this is all it should be doing. So
defer these assignments to the primary C entry code that executes via
the ordinary kernel virtual mapping.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Tested-by: Tom Lendacky <thomas.lendacky@amd.com>
Link: https://lore.kernel.org/r/20240227151907.387873-13-ardb+git@google.com
2024-03-04 18:12:06 +01:00
Ard Biesheuvel
dada858706 x86/startup_64: Simplify CR4 handling in startup code
When paging is enabled, the CR4.PAE and CR4.LA57 control bits cannot be
changed, and so they can simply be preserved rather than reason about
whether or not they need to be set. CR4.MCE should be preserved unless
the kernel was built without CONFIG_X86_MCE, in which case it must be
cleared.

CR4.PSE should be set explicitly, regardless of whether or not it was
set before.

CR4.PGE is set explicitly, and then cleared and set again after
programming CR3 in order to flush TLB entries based on global
translations. This makes the first assignment redundant, and can
therefore be omitted. So clear PGE by omitting it from the preserve
mask, and set it again explicitly after switching to the new page
tables.

  [ bp: Document the exact operation of CR4.PGE ]

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Tested-by: Tom Lendacky <thomas.lendacky@amd.com>
Link: https://lore.kernel.org/r/20240227151907.387873-12-ardb+git@google.com
2024-03-04 18:11:34 +01:00
Thomas Gleixner
35ce64922c x86/idle: Select idle routine only once
The idle routine selection is done on every CPU bringup operation and
has a guard in place which is effective after the first invocation,
which is a pointless exercise.

Invoke it once on the boot CPU and mark the related functions __init.
The guard check has to stay as xen_set_default_idle() runs early.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Link: https://lore.kernel.org/r/87edcu6vaq.ffs@tglx
2024-03-04 17:39:24 +01:00
Thomas Gleixner
5f75916ec6 x86/idle: Let prefer_mwait_c1_over_halt() return bool
The return value is truly boolean. Make it so.

No functional change.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Link: https://lore.kernel.org/r/20240229142248.518723854@linutronix.de
2024-03-04 17:39:24 +01:00
Thomas Gleixner
f3d7eab7be x86/idle: Cleanup idle_setup()
Updating the static call for x86_idle() from idle_setup() is
counter-intuitive.

Let select_idle_routine() handle it like the other idle choices, which
allows to simplify the idle selection later on.

While at it rewrite comments and return a proper error code and not -1.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Link: https://lore.kernel.org/r/20240229142248.455616019@linutronix.de
2024-03-04 17:39:24 +01:00
Thomas Gleixner
0ab562875c x86/idle: Clean up idle selection
Clean up the code to make it readable. No functional change.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Link: https://lore.kernel.org/r/20240229142248.392017685@linutronix.de
2024-03-04 17:39:24 +01:00
Thomas Gleixner
cb81deefb5 x86/idle: Sanitize X86_BUG_AMD_E400 handling
amd_e400_idle(), the idle routine for AMD CPUs which are affected by
erratum 400 violates the RCU constraints by invoking tick_broadcast_enter()
and tick_broadcast_exit() after the core code has marked RCU non-idle.  The
functions can end up in lockdep or tracing, which rightfully triggers a
RCU warning.

The core code provides now a static branch conditional invocation of the
broadcast functions.

Remove amd_e400_idle(), enforce default_idle() and enable the static branch
on affected CPUs to cure this.

  [ bp: Fold in a fix for a IS_ENABLED() check fail missing a "CONFIG_"
    prefix which tglx spotted. ]

Reported-by: Borislav Petkov <bp@alien8.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Link: https://lore.kernel.org/r/877cim6sis.ffs@tglx
2024-03-04 17:38:06 +01:00
Thomas Gleixner
cad860b595 x86/callthunks: Use EXPORT_PER_CPU_SYMBOL_GPL() for per CPU variables
Sparse complains rightfully about the usage of EXPORT_SYMBOL_GPL() for per
CPU variables:

  callthunks.c:346:20: sparse: warning: incorrect type in initializer (different address spaces)
  callthunks.c:346:20: sparse:    expected void const [noderef] __percpu *__vpp_verify
  callthunks.c:346:20: sparse:    got unsigned long long *

Use EXPORT_PER_CPU_SYMBOL_GPL() instead.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20240304005104.841915535@linutronix.de
2024-03-04 12:09:13 +01:00
Thomas Gleixner
ca3ec9e554 x86/cpu: Use EXPORT_PER_CPU_SYMBOL_GPL() for x86_spec_ctrl_current
Sparse rightfully complains:

  bugs.c:71:9: sparse: warning: incorrect type in initializer (different address spaces)
  bugs.c:71:9: sparse:    expected void const [noderef] __percpu *__vpp_verify
  bugs.c:71:9: sparse:    got unsigned long long *

The reason is that x86_spec_ctrl_current which is a per CPU variable is
exported with EXPORT_SYMBOL_GPL().

Use EXPORT_PER_CPU_SYMBOL_GPL() instead.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20240304005104.732288812@linutronix.de
2024-03-04 12:09:13 +01:00
Thomas Gleixner
71eb4893cf x86/percpu: Cure per CPU madness on UP
On UP builds Sparse complains rightfully about accesses to cpu_info with
per CPU accessors:

  cacheinfo.c:282:30: sparse: warning: incorrect type in initializer (different address spaces)
  cacheinfo.c:282:30: sparse:    expected void const [noderef] __percpu *__vpp_verify
  cacheinfo.c:282:30: sparse:    got unsigned int *

The reason is that on UP builds cpu_info which is a per CPU variable on SMP
is mapped to boot_cpu_info which is a regular variable. There is a hideous
accessor cpu_data() which tries to hide this, but it's not sufficient as
some places require raw accessors and generates worse code than the regular
per CPU accessors.

Waste sizeof(struct x86_cpuinfo) memory on UP and provide the per CPU
cpu_info unconditionally. This requires to update the CPU info on the boot
CPU as SMP does. (Ab)use the weakly defined smp_prepare_boot_cpu() function
and implement exactly that.

This allows to use regular per CPU accessors uncoditionally and paves the
way to remove the cpu_data() hackery.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20240304005104.622511517@linutronix.de
2024-03-04 12:09:07 +01:00
Thomas Gleixner
712610725c smp: Consolidate smp_prepare_boot_cpu()
There is no point in having seven architectures implementing the same empty
stub.

Provide a weak function in the init code and remove the stubs.

This also allows to utilize the function on UP which is required to
sanitize the per CPU handling on X86 UP.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20240304005104.567671691@linutronix.de
2024-03-04 12:01:54 +01:00
Thomas Gleixner
154fcf3a78 x86/msr: Prepare for including <linux/percpu.h> into <asm/msr.h>
To clean up the per CPU insanity of UP which causes sparse to be rightfully
unhappy and prevents the usage of the generic per CPU accessors on cpu_info
it is necessary to include <linux/percpu.h> into <asm/msr.h>.

Including <linux/percpu.h> into <asm/msr.h> is impossible because it ends
up in header dependency hell. The problem is that <asm/processor.h>
includes <asm/msr.h>. The inclusion of <linux/percpu.h> results in a
compile fail where the compiler cannot longer handle an include in
<asm/cpufeature.h> which references boot_cpu_data which is
defined in <asm/processor.h>.

The only reason why <asm/msr.h> is included in <asm/processor.h> are the
set/get_debugctlmsr() inlines. They are defined there because <asm/processor.h>
is such a nice dump ground for everything. In fact they belong obviously
into <asm/debugreg.h>.

Move them to <asm/debugreg.h> and fix up the resulting damage which is just
exposing the reliance on random include chains.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20240304005104.454678686@linutronix.de
2024-03-04 12:01:39 +01:00
Ingo Molnar
3c94ba5267 Linux 6.8-rc7
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Merge tag 'v6.8-rc7' into x86/cleanups, to pick up fixes

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2024-03-04 11:54:09 +01:00
Nuno Das Neves
0e3f7d1200 hyperv-tlfs: Change prefix of generic HV_REGISTER_* MSRs to HV_MSR_*
The HV_REGISTER_ are used as arguments to hv_set/get_register(), which
delegate to arch-specific mechanisms for getting/setting synthetic
Hyper-V MSRs.

On arm64, HV_REGISTER_ defines are synthetic VP registers accessed via
the get/set vp registers hypercalls. The naming matches the TLFS
document, although these register names are not specific to arm64.

However, on x86 the prefix HV_REGISTER_ indicates Hyper-V MSRs accessed
via rdmsrl()/wrmsrl(). This is not consistent with the TLFS doc, where
HV_REGISTER_ is *only* used for used for VP register names used by
the get/set register hypercalls.

To fix this inconsistency and prevent future confusion, change the
arch-generic aliases used by callers of hv_set/get_register() to have
the prefix HV_MSR_ instead of HV_REGISTER_.

Use the prefix HV_X64_MSR_ for the x86-only Hyper-V MSRs. On x86, the
generic HV_MSR_'s point to the corresponding HV_X64_MSR_.

Move the arm64 HV_REGISTER_* defines to the asm-generic hyperv-tlfs.h,
since these are not specific to arm64. On arm64, the generic HV_MSR_'s
point to the corresponding HV_REGISTER_.

While at it, rename hv_get/set_registers() and related functions to
hv_get/set_msr(), hv_get/set_nested_msr(), etc. These are only used for
Hyper-V MSRs and this naming makes that clear.

Signed-off-by: Nuno Das Neves <nunodasneves@linux.microsoft.com>
Reviewed-by: Wei Liu <wei.liu@kernel.org>
Reviewed-by: Michael Kelley <mhklinux@outlook.com>
Link: https://lore.kernel.org/r/1708440933-27125-1-git-send-email-nunodasneves@linux.microsoft.com
Signed-off-by: Wei Liu <wei.liu@kernel.org>
Message-ID: <1708440933-27125-1-git-send-email-nunodasneves@linux.microsoft.com>
2024-03-04 06:59:18 +00:00
Jiri Bohac
7fd817c906 x86/e820: Don't reserve SETUP_RNG_SEED in e820
SETUP_RNG_SEED in setup_data is supplied by kexec and should
not be reserved in the e820 map.

Doing so reserves 16 bytes of RAM when booting with kexec.
(16 bytes because data->len is zeroed by parse_setup_data so only
sizeof(setup_data) is reserved.)

When kexec is used repeatedly, each boot adds two entries in the
kexec-provided e820 map as the 16-byte range splits a larger
range of usable memory. Eventually all of the 128 available entries
get used up. The next split will result in losing usable memory
as the new entries cannot be added to the e820 map.

Fixes: 68b8e9713c ("x86/setup: Use rng seeds from setup_data")
Signed-off-by: Jiri Bohac <jbohac@suse.cz>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Cc: <stable@kernel.org>
Link: https://lore.kernel.org/r/ZbmOjKnARGiaYBd5@dwarf.suse.cz
2024-03-01 10:27:20 -08:00
Uros Bizjak
721f791ce1 x86/boot: Use 32-bit XOR to clear registers
x86_64 zero extends 32-bit operations, so for 64-bit operands,
XORL r32,r32 is functionally equal to XORQ r64,r64, but avoids
a REX prefix byte when legacy registers are used.

Slightly smaller code generated, no change in functionality.

Signed-off-by: Uros Bizjak <ubizjak@gmail.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Ard Biesheuvel <ardb@kernel.org>
Link: https://lore.kernel.org/r/20240124103859.611372-1-ubizjak@gmail.com
2024-03-01 12:47:37 +01:00
Borislav Petkov (AMD)
d7b69b590b x86/sev: Dump SEV_STATUS
It is, and will be even more useful in the future, to dump the SEV
features enabled according to SEV_STATUS. Do so:

  [    0.542753] Memory Encryption Features active: AMD SEV SEV-ES SEV-SNP
  [    0.544425] SEV: Status: SEV SEV-ES SEV-SNP DebugSwap

Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Nikunj A Dadhania <nikunj@amd.com>
Link: https://lore.kernel.org/r/20240219094216.GAZdMieDHKiI8aaP3n@fat_crate.local
2024-02-28 13:39:37 +01:00
Brian Gerst
11e36b0f7c x86/boot/64: Load the final kernel GDT during early boot directly, remove startup_gdt[]
Instead of loading a duplicate GDT just for early boot, load the kernel
GDT from its physical address.

Signed-off-by: Brian Gerst <brgerst@gmail.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Ard Biesheuvel <ardb@kernel.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Link: https://lore.kernel.org/r/20240226220544.70769-1-brgerst@gmail.com
2024-02-28 11:02:16 +01:00
Xin Li (Intel)
47403a4b49 x86/nmi: Remove an unnecessary IS_ENABLED(CONFIG_SMP)
IS_ENABLED(CONFIG_SMP) is unnecessary here: smp_processor_id() should
always return zero on UP, and arch_cpu_is_offline() reduces to
!(cpu == 0), so this is a statically false condition on UP.

Suggested-by: H. Peter Anvin (Intel) <hpa@zytor.com>
Signed-off-by: Xin Li (Intel) <xin@zytor.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20240201094604.3918141-1-xin@zytor.com
2024-02-27 22:00:50 +01:00
Ingo Molnar
9b9c280b9a Merge branch 'x86/urgent' into x86/apic, to resolve conflicts
Conflicts:
	arch/x86/kernel/cpu/common.c
	arch/x86/kernel/cpu/intel.c

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2024-02-27 10:09:49 +01:00
Ingo Molnar
6be4ec2968 x86/apic: Build the x86 topology enumeration functions on UP APIC builds too
These functions are mostly pointless on UP, but nevertheless the
64-bit UP APIC build already depends on the existence of
topology_apply_cmdline_limits_early(), which caused a build bug,
resolve it by making them available under CONFIG_X86_LOCAL_APIC,
as their prototypes already are.

Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2024-02-27 10:05:41 +01:00
Kees Cook
44c76825d6 x86: Increase brk randomness entropy for 64-bit systems
In commit c1d171a002 ("x86: randomize brk"), arch_randomize_brk() was
defined to use a 32MB range (13 bits of entropy), but was never increased
when moving to 64-bit. The default arch_randomize_brk() uses 32MB for
32-bit tasks, and 1GB (18 bits of entropy) for 64-bit tasks.

Update x86_64 to match the entropy used by arm64 and other 64-bit
architectures.

Reported-by: y0un9n132@gmail.com
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Jiri Kosina <jkosina@suse.com>
Closes: https://lore.kernel.org/linux-hardening/CA+2EKTVLvc8hDZc+2Yhwmus=dzOUG5E4gV7ayCbu0MPJTZzWkw@mail.gmail.com/
Link: https://lore.kernel.org/r/20240217062545.1631668-1-keescook@chromium.org
2024-02-27 00:23:55 +01:00
Daniel Micay
3c6539b4c1 x86/vdso: Move vDSO to mmap region
The vDSO (and its initial randomization) was introduced in commit 2aae950b21
("x86_64: Add vDSO for x86-64 with gettimeofday/clock_gettime/getcpu"), but
had very low entropy. The entropy was improved in commit 394f56fe48
("x86_64, vdso: Fix the vdso address randomization algorithm"), but there
is still improvement to be made.

In principle there should not be executable code at a low entropy offset
from the stack, since the stack and executable code having separate
randomization is part of what makes ASLR stronger.

Remove the only executable code near the stack region and give the vDSO
the same randomized base as other mmap mappings including the linker
and other shared objects. This results in higher entropy being provided
and there's little to no advantage in separating this from the existing
executable code there. This is already how other architectures like
arm64 handle the vDSO.

As an side, while it's sensible for userspace to reserve the initial mmap
base as a region for executable code with a random gap for other mmap
allocations, along with providing randomization within that region, there
isn't much the kernel can do to help due to how dynamic linkers load the
shared objects.

This was extracted from the PaX RANDMMAP feature.

[kees: updated commit log with historical details and other tweaks]

Signed-off-by: Daniel Micay <danielmicay@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Closes: https://github.com/KSPP/linux/issues/280
Link: https://lore.kernel.org/r/20240210091827.work.233-kees@kernel.org
2024-02-27 00:23:55 +01:00
Breno Leitao
d54e56f31a x86/nmi: Fix the inverse "in NMI handler" check
Commit 344da544f1 ("x86/nmi: Print reasons why backtrace NMIs are
ignored") creates a super nice framework to diagnose NMIs.

Every time nmi_exc() is called, it increments a per_cpu counter
(nsp->idt_nmi_seq). At its exit, it also increments the same counter.  By
reading this counter it can be seen how many times that function was called
(dividing by 2), and, if the function is still being executed, by checking
the idt_nmi_seq's least significant bit.

On the check side (nmi_backtrace_stall_check()), that variable is queried
to check if the NMI is still being executed, but, there is a mistake in the
bitwise operation. That code wants to check if the least significant bit of
the idt_nmi_seq is set or not, but does the opposite, and checks for all
the other bits, which will always be true after the first exc_nmi()
executed successfully.

This appends the misleading string to the dump "(CPU currently in NMI
handler function)"

Fix it by checking the least significant bit, and if it is set, append the
string.

Fixes: 344da544f1 ("x86/nmi: Print reasons why backtrace NMIs are ignored")
Signed-off-by: Breno Leitao <leitao@debian.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Paul E. McKenney <paulmck@kernel.org>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20240207165237.1048837-1-leitao@debian.org
2024-02-26 23:41:30 +01:00
Paolo Bonzini
6890cb1ace x86/cpu/intel: Detect TME keyid bits before setting MTRR mask registers
MKTME repurposes the high bit of physical address to key id for encryption
key and, even though MAXPHYADDR in CPUID[0x80000008] remains the same,
the valid bits in the MTRR mask register are based on the reduced number
of physical address bits.

detect_tme() in arch/x86/kernel/cpu/intel.c detects TME and subtracts
it from the total usable physical bits, but it is called too late.
Move the call to early_init_intel() so that it is called in setup_arch(),
before MTRRs are setup.

This fixes boot on TDX-enabled systems, which until now only worked with
"disable_mtrr_cleanup".  Without the patch, the values written to the
MTRRs mask registers were 52-bit wide (e.g. 0x000fffff_80000800) and
the writes failed; with the patch, the values are 46-bit wide, which
matches the reduced MAXPHYADDR that is shown in /proc/cpuinfo.

Reported-by: Zixi Chen <zixchen@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Cc:stable@vger.kernel.org
Link: https://lore.kernel.org/all/20240131230902.1867092-3-pbonzini%40redhat.com
2024-02-26 08:16:16 -08:00
Paolo Bonzini
9a458198eb x86/cpu: Allow reducing x86_phys_bits during early_identify_cpu()
In commit fbf6449f84 ("x86/sev-es: Set x86_virt_bits to the correct
value straight away, instead of a two-phase approach"), the initialization
of c->x86_phys_bits was moved after this_cpu->c_early_init(c).  This is
incorrect because early_init_amd() expected to be able to reduce the
value according to the contents of CPUID leaf 0x8000001f.

Fortunately, the bug was negated by init_amd()'s call to early_init_amd(),
which does reduce x86_phys_bits in the end.  However, this is very
late in the boot process and, most notably, the wrong value is used for
x86_phys_bits when setting up MTRRs.

To fix this, call get_cpu_address_sizes() as soon as X86_FEATURE_CPUID is
set/cleared, and c->extended_cpuid_level is retrieved.

Fixes: fbf6449f84 ("x86/sev-es: Set x86_virt_bits to the correct value straight away, instead of a two-phase approach")
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Cc:stable@vger.kernel.org
Link: https://lore.kernel.org/all/20240131230902.1867092-2-pbonzini%40redhat.com
2024-02-26 08:16:15 -08:00
Ard Biesheuvel
533568e06b x86/boot/64: Use RIP_REL_REF() to access early_top_pgt[]
early_top_pgt[] is assigned from code that executes from a 1:1 mapping
so it cannot use a plain access from C. Replace the use of
fixup_pointer() with RIP_REL_REF(), which is better and simpler.

For legibility and to align with the code that populates the lower page
table levels, statically initialize the root level page table with an
entry pointing to level3_kernel_pgt[], and overwrite it when needed to
enable 5-level paging.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20240221113506.2565718-24-ardb+git@google.com
2024-02-26 12:58:35 +01:00
Ard Biesheuvel
eb54c2ae4a x86/boot/64: Use RIP_REL_REF() to access early page tables
The early statically allocated page tables are populated from code that
executes from a 1:1 mapping so it cannot use plain accesses from C.
Replace the use of fixup_pointer() with RIP_REL_REF(), which is better
and simpler.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20240221113506.2565718-23-ardb+git@google.com
2024-02-26 12:58:35 +01:00
Ard Biesheuvel
4f8b6cf25f x86/boot/64: Use RIP_REL_REF() to access '__supported_pte_mask'
'__supported_pte_mask' is accessed from code that executes from a 1:1
mapping so it cannot use a plain access from C. Replace the use of
fixup_pointer() with RIP_REL_REF(), which is better and simpler.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20240221113506.2565718-22-ardb+git@google.com
2024-02-26 12:58:35 +01:00
Ard Biesheuvel
b0fe5fb609 x86/boot/64: Use RIP_REL_REF() to access early_dynamic_pgts[]
early_dynamic_pgts[] and next_early_pgt are accessed from code that
executes from a 1:1 mapping so it cannot use a plain access from C.
Replace the use of fixup_pointer() with RIP_REL_REF(), which is better
and simpler.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20240221113506.2565718-21-ardb+git@google.com
2024-02-26 12:58:35 +01:00
Ard Biesheuvel
d9ec115805 x86/boot/64: Use RIP_REL_REF() to assign 'phys_base'
'phys_base' is assigned from code that executes from a 1:1 mapping so it
cannot use a plain access from C. Replace the use of fixup_pointer()
with RIP_REL_REF(), which is better and simpler.

While at it, move the assignment to before the addition of the SME mask
so there is no need to subtract it again, and drop the unnecessary
addition ('phys_base' is statically initialized to 0x0)

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20240221113506.2565718-20-ardb+git@google.com
2024-02-26 12:58:35 +01:00