kernel.git/arch/x86/platform, branch linux-5.13.y

x86/setup: Always reserve the first 1M of RAM

2021-06-03T17:57:55Z

There are BIOSes that are known to corrupt the memory under 1M, or more precisely under 640K because the memory above 640K is anyway reserved for the EGA/VGA frame buffer and BIOS. To prevent usage of the memory that will be potentially clobbered by the kernel, the beginning of the memory is always reserved. The exact size of the reserved area is determined by CONFIG_X86_RESERVE_LOW build time and the "reservelow=" command line option. The reserved range may be from 4K to 640K with the default of 64K. There are also configurations that reserve the entire 1M range, like machines with SandyBridge graphic devices or systems that enable crash kernel. In addition to the potentially clobbered memory, EBDA of unknown size may be as low as 128K and the memory above that EBDA start is also reserved early. It would have been possible to reserve the entire range under 1M unless for the real mode trampoline that must reside in that area. To accommodate placement of the real mode trampoline and keep the memory safe from being clobbered by BIOS, reserve the first 64K of RAM before memory allocations are possible and then, after the real mode trampoline is allocated, reserve the entire range from 0 to 1M. Update trim_snb_memory() and reserve_real_mode() to avoid redundant reservations of the same memory range. Also make sure the memory under 1M is not getting freed by efi_free_boot_services(). [ bp: Massage commit message and comments. ] Fixes: a799c2bd29d1 ("x86/setup: Consolidate early memory reservations") Signed-off-by: Mike Rapoport Signed-off-by: Borislav Petkov Tested-by: Hugh Dickins Link: https://bugzilla.kernel.org/show_bug.cgi?id=213177 Link: https://lkml.kernel.org/r/20210601075354.5149-2-rppt@kernel.org

x86/sev-es: Rename sev-es.{ch} to sev.{ch}

2021-05-10T05:40:27Z

SEV-SNP builds upon the SEV-ES functionality while adding new hardware protection. Version 2 of the GHCB specification adds new NAE events that are SEV-SNP specific. Rename the sev-es.{ch} to sev.{ch} so that all SEV* functionality can be consolidated in one place. Signed-off-by: Brijesh Singh Signed-off-by: Borislav Petkov Acked-by: Joerg Roedel Link: https://lkml.kernel.org/r/20210427111636.1207-2-brijesh.singh@amd.com

Merge tag 'x86_core_for_v5.13' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2021-04-28T00:45:09Z

Pull x86 updates from Borislav Petkov: - Turn the stack canary into a normal __percpu variable on 32-bit which gets rid of the LAZY_GS stuff and a lot of code. - Add an insn_decode() API which all users of the instruction decoder should preferrably use. Its goal is to keep the details of the instruction decoder away from its users and simplify and streamline how one decodes insns in the kernel. Convert its users to it. - kprobes improvements and fixes - Set the maximum DIE per package variable on Hygon - Rip out the dynamic NOP selection and simplify all the machinery around selecting NOPs. Use the simplified NOPs in objtool now too. - Add Xeon Sapphire Rapids to list of CPUs that support PPIN - Simplify the retpolines by folding the entire thing into an alternative now that objtool can handle alternatives with stack ops. Then, have objtool rewrite the call to the retpoline with the alternative which then will get patched at boot time. - Document Intel uarch per models in intel-family.h - Make Sub-NUMA Clustering topology the default and Cluster-on-Die the exception on Intel. * tag 'x86_core_for_v5.13' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (53 commits) x86, sched: Treat Intel SNC topology as default, COD as exception x86/cpu: Comment Skylake server stepping too x86/cpu: Resort and comment Intel models objtool/x86: Rewrite retpoline thunk calls objtool: Skip magical retpoline .altinstr_replacement objtool: Cache instruction relocs objtool: Keep track of retpoline call sites objtool: Add elf_create_undef_symbol() objtool: Extract elf_symbol_add() objtool: Extract elf_strtab_concat() objtool: Create reloc sections implicitly objtool: Add elf_create_reloc() helper objtool: Rework the elf_rebuild_reloc_section() logic objtool: Fix static_call list generation objtool: Handle per arch retpoline naming objtool: Correctly handle retpoline thunk calls x86/retpoline: Simplify retpolines x86/alternatives: Optimize optimize_nops() x86: Add insn_decode_kernel() x86/kprobes: Move 'inline' to the beginning of the kprobe_is_ss() declaration ...

Merge tag 'x86_platform_for_v5.13' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2021-04-26T16:34:19Z

Pull x86 platform updates from Borislav Petkov: "A bunch of SGI UV improvements, fixes and cleanups" * tag 'x86_platform_for_v5.13' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/platform/uv: Remove dead !CONFIG_KEXEC_CORE code x86/platform/uv: Fix !KEXEC build failure x86/platform/uv: Add more to secondary CPU kdump info x86/platform/uv: Use x2apic enabled bit as set by BIOS to indicate APIC mode x86/platform/uv: Set section block size for hubless architectures x86/platform/uv: Fix indentation warning in Documentation/ABI/testing/sysfs-firmware-sgi_uv

x86/platform/uv: Remove dead !CONFIG_KEXEC_CORE code

2021-04-20T08:08:34Z

The !CONFIG_KEXEC_CORE code in arch/x86/platform/uv/uv_nmi.c was unused, untested and didn't even build for 7 years. Since we fixed this by requiring X86_UV to depend on CONFIG_KEXEC_CORE, remove the (now) dead code. Also move the uv_nmi_kexec_failed definition back up to where the other file-scope global variables are defined. Signed-off-by: Ingo Molnar Cc: Mike Travis Cc: linux-kernel@vger.kernel.org

x86/platform/uv: Add more to secondary CPU kdump info

2021-04-16T10:51:41Z

Add call to run_crash_ipi_callback() to gather more info of what the secondary CPUs were doing to help with failure analysis. Excerpt from Georges: 'It is only changing where crash secondaries will be stalling after having taken care of properly laying down "crash note regs". Please note that "crash note regs" are a key piece of data used by crash dump debuggers to provide a reliable backtrace of running processors.' Secondary change pursuant to a5f526ecb075 ("CodingStyle: Inclusive Terminology"): change master/slave to main/secondary. [ bp: Massage commit message. ] Signed-off-by: Georges Aureau Signed-off-by: Mike Travis Signed-off-by: Borislav Petkov Reviewed-by: Steve Wahl Link: https://lkml.kernel.org/r/20210311151028.82678-1-mike.travis@hpe.com

x86/platform/intel/quark: Fix incorrect kernel-doc comment syntax in files

2021-04-10T11:59:25Z

The opening comment mark '/**' is used for highlighting the beginning of kernel-doc comments. There are certain files in arch/x86/platform/intel-quark, which follow this syntax, but the content inside does not comply with kernel-doc. Such lines were probably not meant for kernel-doc parsing, but are parsed due to the presence of kernel-doc like comment syntax(i.e, '/**'), which causes unexpected warnings from kernel-doc. E.g., presence of kernel-doc like comment in the header lines for arch/x86/platform/intel-quark/imr.c causes these warnings: "warning: Function parameter or member 'fmt' not described in 'pr_fmt'" "warning: expecting prototype for c(). Prototype was for pr_fmt() instead" Similarly for arch/x86/platform/intel-quark/imr_selftest.c too. Provide a simple fix by replacing these occurrences with general comment format, i.e. '/*', to prevent kernel-doc from parsing it. Signed-off-by: Aditya Srivastava Signed-off-by: Thomas Gleixner Acked-by: Randy Dunlap Link: https://lore.kernel.org/r/20210330213022.28769-1-yashsri421@gmail.com

Merge tag 'v5.12-rc5' into WIP.x86/core, to pick up recent NOP related changes

2021-04-02T10:33:16Z

In particular we want to have this upstream commit: b90829704780: ("bpf: Use NOP_ATOMIC5 instead of emit_nops(&prog, 5) for BPF_TRAMP_F_CALL_ORIG") ... before merging in x86/cpu changes and the removal of the NOP optimizations, and applying PeterZ's !retpoline objtool series. Signed-off-by: Ingo Molnar

x86: Fix various typos in comments, take #2

2021-03-21T22:50:28Z

Fix another ~42 single-word typos in arch/x86/ code comments, missed a few in the first pass, in particular in .S files. Signed-off-by: Ingo Molnar Cc: Borislav Petkov Cc: Thomas Gleixner Cc: Peter Zijlstra Cc: Paolo Bonzini Cc: Bjorn Helgaas Cc: linux-kernel@vger.kernel.org

x86: Remove unusual Unicode characters from comments

2021-03-21T22:50:07Z

We've accumulated a few unusual Unicode characters in arch/x86/ over the years, substitute them with their proper ASCII equivalents. A few of them were a whitespace equivalent: ' ' - the use was harmless. Signed-off-by: Ingo Molnar Cc: Borislav Petkov Cc: Thomas Gleixner Cc: Peter Zijlstra Cc: linux-kernel@vger.kernel.org