kernel.git/arch/x86/boot, branch linux-6.4.y

x86/decompressor: Don't rely on upper 32 bits of GPRs being preserved

2023-09-13T07:47:58Z

[ Upstream commit 264b82fdb4989cf6a44a2bcd0c6ea05e8026b2ac ] The 4-to-5 level mode switch trampoline disables long mode and paging in order to be able to flick the LA57 bit. According to section 3.4.1.1 of the x86 architecture manual [0], 64-bit GPRs might not retain the upper 32 bits of their contents across such a mode switch. Given that RBP, RBX and RSI are live at this point, preserve them on the stack, along with the return address that might be above 4G as well. [0] Intel® 64 and IA-32 Architectures Software Developer’s Manual, Volume 1: Basic Architecture "Because the upper 32 bits of 64-bit general-purpose registers are undefined in 32-bit modes, the upper 32 bits of any general-purpose register are not preserved when switching from 64-bit mode to a 32-bit mode (to protected mode or compatibility mode). Software must not depend on these bits to maintain a value after a 64-bit to 32-bit mode switch." Fixes: 194a9749c73d650c ("x86/boot/compressed/64: Handle 5-level paging boot if kernel is above 4G") Signed-off-by: Ard Biesheuvel Signed-off-by: Borislav Petkov (AMD) Link: https://lore.kernel.org/r/20230807162720.545787-2-ardb@kernel.org Signed-off-by: Sasha Levin

x86/sev: Do not try to parse for the CC blob on non-AMD hardware

2023-08-16T16:32:22Z

commit bee6cf1a80b54548a039e224c651bb15b644a480 upstream. Tao Liu reported a boot hang on an Intel Atom machine due to an unmapped EFI config table. The reason being that the CC blob which contains the CPUID page for AMD SNP guests is parsed for before even checking whether the machine runs on AMD hardware. Usually that's not a problem on !AMD hw - it simply won't find the CC blob's GUID and return. However, if any parts of the config table pointers array is not mapped, the kernel will #PF very early in the decompressor stage without any opportunity to recover. Therefore, do a superficial CPUID check before poking for the CC blob. This will fix the current issue on real hardware. It would also work as a guest on a non-lying hypervisor. For the lying hypervisor, the check is done again, *after* parsing the CC blob as the real CPUID page will be present then. Clear the #VC handler in case SEV-{ES,SNP} hasn't been detected, as a precaution. Fixes: c01fce9cef84 ("x86/compressed: Add SEV-SNP feature detection/setup") Reported-by: Tao Liu Signed-off-by: Borislav Petkov (AMD) Acked-by: Tom Lendacky Tested-by: Tao Liu Cc: Link: https://lore.kernel.org/r/20230601072043.24439-1-ltao@redhat.com Signed-off-by: Greg Kroah-Hartman

Merge tag 'x86_tdx_for_6.4' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2023-04-28T16:36:09Z

Pull x86 tdx update from Dave Hansen: "The original tdx hypercall assembly code took two flags in %RSI to tweak its behavior at runtime. PeterZ recently axed one flag in commit e80a48bade61 ("x86/tdx: Remove TDX_HCALL_ISSUE_STI"). Kill the other flag too and tweak the 'output' mode with an assembly macro instead. This results in elimination of one push/pop pair and overall easier to read assembly. - Do conditional __tdx_hypercall() 'output' processing via an assembly macro argument rather than a runtime register" * tag 'x86_tdx_for_6.4' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/tdx: Drop flags from __tdx_hypercall()

Merge tag 'x86_cleanups_for_v6.4_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2023-04-28T16:22:30Z

Pull x86 cleanups from Borislav Petkov: - Unify duplicated __pa() and __va() definitions - Simplify sysctl tables registration - Remove unused symbols - Correct function name in comment * tag 'x86_cleanups_for_v6.4_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/boot: Centralize __pa()/__va() definitions x86: Simplify one-level sysctl registration for itmt_kern_table x86: Simplify one-level sysctl registration for abi_table2 x86/platform/intel-mid: Remove unused definitions from intel-mid.h x86/uaccess: Remove memcpy_page_flushcache() x86/entry: Change stale function name in comment to error_return()

x86/boot: Centralize pa()/va() definitions

2023-04-04T20:42:37Z

Replace multiple __pa()/__va() definitions with a single one in misc.h. Signed-off-by: Kirill A. Shutemov Signed-off-by: Dave Hansen Reviewed-by: David Hildenbrand Reviewed-by: Mike Rapoport Reviewed-by: Dave Hansen Link: https://lore.kernel.org/all/20230330114956.20342-2-kirill.shutemov%40linux.intel.com

docs: move x86 documentation into Documentation/arch/

2023-03-30T18:58:51Z

Move the x86 documentation under Documentation/arch/ as a way of cleaning up the top-level directory and making the structure of our docs more closely match the structure of the source directories it describes. All in-kernel references to the old paths have been updated. Acked-by: Dave Hansen Cc: linux-arch@vger.kernel.org Cc: x86@kernel.org Cc: Borislav Petkov Cc: Thomas Gleixner Link: https://lore.kernel.org/lkml/20230315211523.108836-1-corbet@lwn.net/ Signed-off-by: Jonathan Corbet

x86/tdx: Drop flags from __tdx_hypercall()

2023-03-22T18:36:05Z

After TDX_HCALL_ISSUE_STI got dropped, the only flag left is TDX_HCALL_HAS_OUTPUT. The flag indicates if the caller wants to see tdx_hypercall_args updated based on the hypercall output. Drop the flags and provide __tdx_hypercall_ret() that matches TDX_HCALL_HAS_OUTPUT semantics. Suggested-by: Peter Zijlstra Signed-off-by: Kirill A. Shutemov Signed-off-by: Dave Hansen Acked-by: Peter Zijlstra (Intel) Link: https://lore.kernel.org/all/20230321003511.9469-1-kirill.shutemov%40linux.intel.com

Merge tag 'kbuild-v6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

2023-02-26T19:53:25Z

Pull Kbuild updates from Masahiro Yamada: - Change V=1 option to print both short log and full command log - Allow V=1 and V=2 to be combined as V=12 - Make W=1 detect wrong .gitignore files - Tree-wide cleanups for unused command line arguments passed to Clang - Stop using -Qunused-arguments with Clang - Make scripts/setlocalversion handle only correct release tags instead of any arbitrary annotated tag - Create Debian and RPM source packages without cleaning the source tree - Various cleanups for packaging * tag 'kbuild-v6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (74 commits) kbuild: rpm-pkg: remove unneeded KERNELRELEASE from modules/headers_install docs: kbuild: remove description of KBUILD_LDS_MODULE .gitattributes: use 'dts' diff driver for *.dtso files kbuild: deb-pkg: improve the usability of source package kbuild: deb-pkg: fix binary-arch and clean in debian/rules kbuild: tar-pkg: use tar rules in scripts/Makefile.package kbuild: make perf-tar*-src-pkg work without relying on git kbuild: deb-pkg: switch over to source format 3.0 (quilt) kbuild: deb-pkg: make .orig tarball a hard link if possible kbuild: deb-pkg: hide KDEB_SOURCENAME from Makefile kbuild: srcrpm-pkg: create source package without cleaning kbuild: rpm-pkg: build binary packages from source rpm kbuild: deb-pkg: create source package without cleaning kbuild: add a tool to list files ignored by git Documentation/llvm: add Chimera Linux, Google and Meta datacenters setlocalversion: use only the correct release tag for git-describe setlocalversion: clean up the construction of version output .gitignore: ignore *.cover and *.mbx kbuild: remove --include-dir MAKEFLAG from top Makefile kbuild: fix trivial typo in comment ...

Merge tag 'x86-boot-2023-02-20' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2023-02-21T02:32:55Z

Pull x86 boot updates from Ingo Molnar: - Robustify/fix calling startup_{32,64}() from the decompressor code, and removing x86 quirk from scripts/head-object-list.txt as a result. - Do not register processors that cannot be onlined for x2APIC * tag 'x86-boot-2023-02-20' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/acpi/boot: Do not register processors that cannot be onlined for x2APIC scripts/head-object-list: Remove x86 from the list x86/boot: Robustify calling startup_{32,64}() from the decompressor code

Merge tag 'v6.2-rc6' into sched/core, to pick up fixes

2023-01-31T14:01:20Z

Pick up fixes before merging another batch of cpuidle updates. Signed-off-by: Ingo Molnar