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2023-10-11x86/sev: Move sev_setup_arch() to mem_encrypt.cAlexander Shishkin
Since commit: 4d96f9109109b ("x86/sev: Replace occurrences of sev_active() with cc_platform_has()") ... the SWIOTLB bounce buffer size adjustment and restricted virtio memory setting also inadvertently apply to TDX: the code is using cc_platform_has(CC_ATTR_GUEST_MEM_ENCRYPT) as a gatekeeping condition, which is also true for TDX, and this is also what we want. To reflect this, move the corresponding code to generic mem_encrypt.c. No functional changes intended. Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Reviewed-by: Tom Lendacky <thomas.lendacky@amd.com> Link: https://lore.kernel.org/r/20231010145220.3960055-2-alexander.shishkin@linux.intel.com
2023-10-04x86: kdump: use generic interface to simplify crashkernel reservation codeBaoquan He
With the help of newly changed function parse_crashkernel() and generic reserve_crashkernel_generic(), crashkernel reservation can be simplified by steps: 1) Add a new header file <asm/crash_core.h>, and define CRASH_ALIGN, CRASH_ADDR_LOW_MAX, CRASH_ADDR_HIGH_MAX and DEFAULT_CRASH_KERNEL_LOW_SIZE in <asm/crash_core.h>; 2) Add arch_reserve_crashkernel() to call parse_crashkernel() and reserve_crashkernel_generic(), and do the ARCH specific work if needed. 3) Add ARCH_HAS_GENERIC_CRASHKERNEL_RESERVATION Kconfig in arch/x86/Kconfig. When adding DEFAULT_CRASH_KERNEL_LOW_SIZE, add crash_low_size_default() to calculate crashkernel low memory because x86_64 has special requirement. The old reserve_crashkernel_low() and reserve_crashkernel() can be removed. [bhe@redhat.com: move crash_low_size_default() code into <asm/crash_core.h>] Link: https://lkml.kernel.org/r/ZQpeAjOmuMJBFw1/@MiWiFi-R3L-srv Link: https://lkml.kernel.org/r/20230914033142.676708-7-bhe@redhat.com Signed-off-by: Baoquan He <bhe@redhat.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Chen Jiahao <chenjiahao16@huawei.com> Cc: Zhen Lei <thunder.leizhen@huawei.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-10-04crash_core: change the prototype of function parse_crashkernel()Baoquan He
Add two parameters 'low_size' and 'high' to function parse_crashkernel(), later crashkernel=,high|low parsing will be added. Make adjustments in all call sites of parse_crashkernel() in arch. Link: https://lkml.kernel.org/r/20230914033142.676708-3-bhe@redhat.com Signed-off-by: Baoquan He <bhe@redhat.com> Reviewed-by: Zhen Lei <thunder.leizhen@huawei.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Chen Jiahao <chenjiahao16@huawei.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-10-02x86/of: Move the x86_flattree_get_config() call out of x86_dtb_init()Saurabh Sengar
Fetching the device tree configuration before initmem_init() is necessary to allow the parsing of NUMA node information. However moving the entire x86_dtb_init() call before initmem_init() is not correct as APIC/IO-APIC enumeration has to be after initmem_init(). Thus, move the x86_flattree_get_config() call out of x86_dtb_init(), into setup_arch(), to call it before initmem_init(), and leave the ACPI/IOAPIC registration sequence as-is. [ mingo: Updated the changelog for clarity. ] Signed-off-by: Saurabh Sengar <ssengar@linux.microsoft.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Link: https://lore.kernel.org/r/1692949657-16446-1-git-send-email-ssengar@linux.microsoft.com
2023-09-18x86/mm, kexec, ima: Use memblock_free_late() from ima_free_kexec_buffer()Rik van Riel
The code calling ima_free_kexec_buffer() runs long after the memblock allocator has already been torn down, potentially resulting in a use after free in memblock_isolate_range(). With KASAN or KFENCE, this use after free will result in a BUG from the idle task, and a subsequent kernel panic. Switch ima_free_kexec_buffer() over to memblock_free_late() to avoid that bug. Fixes: fee3ff99bc67 ("powerpc: Move arch independent ima kexec functions to drivers/of/kexec.c") Suggested-by: Mike Rappoport <rppt@kernel.org> Signed-off-by: Rik van Riel <riel@surriel.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Link: https://lore.kernel.org/r/20230817135558.67274c83@imladris.surriel.com
2023-08-09x86/apic: Provide apic_update_callback()Thomas Gleixner
There are already two variants of update mechanism for particular callbacks and virtualization just writes into the data structure. Provide an interface and use a shadow data structure to preserve callbacks so they can be reapplied when the APIC driver is replaced. The extra data structure is intentional as any new callback needs to be also updated in the core code. This also prepares for static calls. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Tested-by: Michael Kelley <mikelley@microsoft.com> Tested-by: Sohil Mehta <sohil.mehta@intel.com> Tested-by: Juergen Gross <jgross@suse.com> # Xen PV (dom0 and unpriv. guest)
2023-08-09x86/apic: Mop up *setup_apic_routing()Thomas Gleixner
default_setup_apic_routing() is a complete misnomer. On 64bit it does the actual APIC probing and on 32bit it is used to force select the bigsmp APIC and to emit a redundant message in the apic::setup_apic_routing() callback. Rename the 64bit and 32bit function so they reflect what they are doing and remove the useless APIC callback. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Tested-by: Michael Kelley <mikelley@microsoft.com> Tested-by: Sohil Mehta <sohil.mehta@intel.com> Tested-by: Juergen Gross <jgross@suse.com> # Xen PV (dom0 and unpriv. guest)
2023-08-09x86/apic/32: Decrapify the def_bigsmp mechanismThomas Gleixner
If the system has more than 8 CPUs then XAPIC and the bigsmp APIC driver is required. This is ensured via: 1) Enumerating all possible CPUs up to NR_CPUS 2) Checking at boot CPU APIC setup time whether the system has more than 8 CPUs and has an XAPIC. If that's the case then it's attempted to install the bigsmp APIC driver and a magic variable 'def_to_bigsmp' is set to one. 3) If that magic variable is set and CONFIG_X86_BIGSMP=n and the system has more than 8 CPUs smp_sanity_check() removes all CPUs >= #8 from the present and possible mask in the most convoluted way. This logic is completely broken for the case where the bigsmp driver is enabled, but not selected due to a command line option specifying the default APIC. In that case the system boots with default APIC in logical destination mode and fails to reduce the number of CPUs. That aside the above which is sprinkled over 3 different places is yet another piece of art. It would have been too obvious to check the requirements upfront and limit nr_cpu_ids _before_ enumerating tons of CPUs and then removing them again. Implement exactly this. Check the bigsmp requirement when the boot APIC is registered which happens _before_ ACPI/MPTABLE parsing and limit the number of CPUs to 8 if it can't be used. Switch it over when the boot CPU apic is set up if necessary. [ dhansen: fix nr_cpu_ids off-by-one in default_setup_apic_routing() ] Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Tested-by: Michael Kelley <mikelley@microsoft.com> Tested-by: Sohil Mehta <sohil.mehta@intel.com> Tested-by: Juergen Gross <jgross@suse.com> # Xen PV (dom0 and unpriv. guest)
2023-08-09x86/apic: Rename disable_apicThomas Gleixner
It reflects a state and not a command. Make it bool while at it. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Tested-by: Michael Kelley <mikelley@microsoft.com> Tested-by: Sohil Mehta <sohil.mehta@intel.com> Tested-by: Juergen Gross <jgross@suse.com> # Xen PV (dom0 and unpriv. guest)
2023-06-27Merge tag 'for-linus-6.5-rc1-tag' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip Pull xen updates from Juergen Gross: - three patches adding missing prototypes - a fix for finding the iBFT in a Xen dom0 for supporting diskless iSCSI boot * tag 'for-linus-6.5-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: x86: xen: add missing prototypes x86/xen: add prototypes for paravirt mmu functions iscsi_ibft: Fix finding the iBFT under Xen Dom 0 xen: xen_debug_interrupt prototype to global header
2023-06-26iscsi_ibft: Fix finding the iBFT under Xen Dom 0Ross Lagerwall
To facilitate diskless iSCSI boot, the firmware can place a table of configuration details in memory called the iBFT. The presence of this table is not specified, nor is the precise location (and it's not in the E820) so the kernel has to search for a magic marker to find it. When running under Xen, Dom 0 does not have access to the entire host's memory, only certain regions which are identity-mapped which means that the pseudo-physical address in Dom0 == real host physical address. Add the iBFT search bounds as a reserved region which causes it to be identity-mapped in xen_set_identity_and_remap_chunk() which allows Dom0 access to the specific physical memory to correctly search for the iBFT magic marker (and later access the full table). This necessitates moving the call to reserve_ibft_region() somewhat later so that it is called after e820__memory_setup() which is when the Xen identity mapping adjustments are applied. The precise location of the call is not too important so I've put it alongside dmi_setup() which does similar scanning of memory for configuration tables. Finally in the iBFT find code, instead of using isa_bus_to_virt() which doesn't do the right thing under Xen, use early_memremap() like the dmi_setup() code does. The result of these changes is that it is possible to boot a diskless Xen + Dom0 running off an iSCSI disk whereas previously it would fail to find the iBFT and consequently, the iSCSI root disk. Signed-off-by: Ross Lagerwall <ross.lagerwall@citrix.com> Reviewed-by: Juergen Gross <jgross@suse.com> Acked-by: Konrad Rzeszutek Wilk <konrad@darnok.org> Acked-by: Dave Hansen <dave.hansen@linux.intel.com> # for x86 Link: https://lore.kernel.org/r/20230605102840.1521549-1-ross.lagerwall@citrix.com Signed-off-by: Juergen Gross <jgross@suse.com>
2023-06-01x86/mtrr: Support setting MTRR state for software defined MTRRsJuergen Gross
When running virtualized, MTRR access can be reduced (e.g. in Xen PV guests or when running as a SEV-SNP guest under Hyper-V). Typically, the hypervisor will not advertize the MTRR feature in CPUID data, resulting in no MTRR memory type information being available for the kernel. This has turned out to result in problems (Link tags below): - Hyper-V SEV-SNP guests using uncached mappings where they shouldn't - Xen PV dom0 mapping memory as WB which should be UC- instead Solve those problems by allowing an MTRR static state override, overwriting the empty state used today. In case such a state has been set, don't call get_mtrr_state() in mtrr_bp_init(). The set state will only be used by mtrr_type_lookup(), as in all other cases mtrr_enabled() is being checked, which will return false. Accept the overwrite call only for selected cases when running as a guest. Disable X86_FEATURE_MTRR in order to avoid any MTRR modifications by just refusing them. [ bp: Massage. ] Signed-off-by: Juergen Gross <jgross@suse.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Tested-by: Michael Kelley <mikelley@microsoft.com> Link: https://lore.kernel.org/all/4fe9541e-4d4c-2b2a-f8c8-2d34a7284930@nerdbynature.de/ Link: https://lore.kernel.org/lkml/BYAPR21MB16883ABC186566BD4D2A1451D7FE9@BYAPR21MB1688.namprd21.prod.outlook.com Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
2023-01-11x86/setup: Move duplicate boot_cpu_data definition out of the ifdefferyYuntao Wang
Both the if and else blocks define an exact same boot_cpu_data variable, move the duplicate variable definition out of the if/else block. In addition, do some other minor cleanups. [ bp: Massage. ] Signed-off-by: Yuntao Wang <ytcoode@gmail.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Link: https://lore.kernel.org/r/20220601122914.820890-1-ytcoode@gmail.com
2022-12-13Merge tag 'x86_cpu_for_v6.2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 cpu updates from Borislav Petkov: - Split MTRR and PAT init code to accomodate at least Xen PV and TDX guests which do not get MTRRs exposed but only PAT. (TDX guests do not support the cache disabling dance when setting up MTRRs so they fall under the same category) This is a cleanup work to remove all the ugly workarounds for such guests and init things separately (Juergen Gross) - Add two new Intel CPUs to the list of CPUs with "normal" Energy Performance Bias, leading to power savings - Do not do bus master arbitration in C3 (ARB_DISABLE) on modern Centaur CPUs * tag 'x86_cpu_for_v6.2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (26 commits) x86/mtrr: Make message for disabled MTRRs more descriptive x86/pat: Handle TDX guest PAT initialization x86/cpuid: Carve out all CPUID functionality x86/cpu: Switch to cpu_feature_enabled() for X86_FEATURE_XENPV x86/cpu: Remove X86_FEATURE_XENPV usage in setup_cpu_entry_area() x86/cpu: Drop 32-bit Xen PV guest code in update_task_stack() x86/cpu: Remove unneeded 64-bit dependency in arch_enter_from_user_mode() x86/cpufeatures: Add X86_FEATURE_XENPV to disabled-features.h x86/acpi/cstate: Optimize ARB_DISABLE on Centaur CPUs x86/mtrr: Simplify mtrr_ops initialization x86/cacheinfo: Switch cache_ap_init() to hotplug callback x86: Decouple PAT and MTRR handling x86/mtrr: Add a stop_machine() handler calling only cache_cpu_init() x86/mtrr: Let cache_aps_delayed_init replace mtrr_aps_delayed_init x86/mtrr: Get rid of __mtrr_enabled bool x86/mtrr: Simplify mtrr_bp_init() x86/mtrr: Remove set_all callback from struct mtrr_ops x86/mtrr: Disentangle MTRR init from PAT init x86/mtrr: Move cache control code to cacheinfo.c x86/mtrr: Split MTRR-specific handling from cache dis/enabling ...
2022-12-13Merge tag 'x86_boot_for_v6.2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 boot updates from Borislav Petkov: "A of early boot cleanups and fixes. - Do some spring cleaning to the compressed boot code by moving the EFI mixed-mode code to a separate compilation unit, the AMD memory encryption early code where it belongs and fixing up build dependencies. Make the deprecated EFI handover protocol optional with the goal of removing it at some point (Ard Biesheuvel) - Skip realmode init code on Xen PV guests as it is not needed there - Remove an old 32-bit PIC code compiler workaround" * tag 'x86_boot_for_v6.2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/boot: Remove x86_32 PIC using %ebx workaround x86/boot: Skip realmode init code when running as Xen PV guest x86/efi: Make the deprecated EFI handover protocol optional x86/boot/compressed: Only build mem_encrypt.S if AMD_MEM_ENCRYPT=y x86/boot/compressed: Adhere to calling convention in get_sev_encryption_bit() x86/boot/compressed: Move startup32_check_sev_cbit() out of head_64.S x86/boot/compressed: Move startup32_check_sev_cbit() into .text x86/boot/compressed: Move startup32_load_idt() out of head_64.S x86/boot/compressed: Move startup32_load_idt() into .text section x86/boot/compressed: Pull global variable reference into startup32_load_idt() x86/boot/compressed: Avoid touching ECX in startup32_set_idt_entry() x86/boot/compressed: Simplify IDT/GDT preserve/restore in the EFI thunk x86/boot/compressed, efi: Merge multiple definitions of image_offset into one x86/boot/compressed: Move efi32_pe_entry() out of head_64.S x86/boot/compressed: Move efi32_entry out of head_64.S x86/boot/compressed: Move efi32_pe_entry into .text section x86/boot/compressed: Move bootargs parsing out of 32-bit startup code x86/boot/compressed: Move 32-bit entrypoint code into .text section x86/boot/compressed: Rename efi_thunk_64.S to efi-mixed.S
2022-11-25x86/boot: Skip realmode init code when running as Xen PV guestJuergen Gross
When running as a Xen PV guest there is no need for setting up the realmode trampoline, as realmode isn't supported in this environment. Trying to setup the trampoline has been proven to be problematic in some cases, especially when trying to debug early boot problems with Xen requiring to keep the EFI boot-services memory mapped (some firmware variants seem to claim basically all memory below 1Mb for boot services). Introduce new x86_platform_ops operations for that purpose, which can be set to a NOP by the Xen PV specific kernel boot code. [ bp: s/call_init_real_mode/do_init_real_mode/ ] Fixes: 084ee1c641a0 ("x86, realmode: Relocator for realmode code") Suggested-by: H. Peter Anvin <hpa@zytor.com> Signed-off-by: Juergen Gross <jgross@suse.com> Signed-off-by: Borislav Petkov <bp@suse.de> Link: https://lore.kernel.org/r/20221123114523.3467-1-jgross@suse.com
2022-11-18efi: memmap: Move EFI fake memmap support into x86 arch treeArd Biesheuvel
The EFI fake memmap support is specific to x86, which manipulates the EFI memory map in various different ways after receiving it from the EFI stub. On other architectures, we have managed to push back on this, and the EFI memory map is kept pristine. So let's move the fake memmap code into the x86 arch tree, where it arguably belongs. Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2022-11-10x86: Decouple PAT and MTRR handlingJuergen Gross
Today, PAT is usable only with MTRR being active, with some nasty tweaks to make PAT usable when running as a Xen PV guest which doesn't support MTRR. The reason for this coupling is that both PAT MSR changes and MTRR changes require a similar sequence and so full PAT support was added using the already available MTRR handling. Xen PV PAT handling can work without MTRR, as it just needs to consume the PAT MSR setting done by the hypervisor without the ability and need to change it. This in turn has resulted in a convoluted initialization sequence and wrong decisions regarding cache mode availability due to misguiding PAT availability flags. Fix all of that by allowing to use PAT without MTRR and by reworking the current PAT initialization sequence to match better with the newly introduced generic cache initialization. This removes the need of the recently added pat_force_disabled flag, so remove the remnants of the patch adding it. Signed-off-by: Juergen Gross <jgross@suse.com> Signed-off-by: Borislav Petkov <bp@suse.de> Link: https://lore.kernel.org/r/20221102074713.21493-14-jgross@suse.com Signed-off-by: Borislav Petkov <bp@suse.de>
2022-11-10x86/mtrr: Add a stop_machine() handler calling only cache_cpu_init()Juergen Gross
Instead of having a stop_machine() handler for either a specific MTRR register or all state at once, add a handler just for calling cache_cpu_init() if appropriate. Add functions for calling stop_machine() with this handler as well. Add a generic replacement for mtrr_bp_restore() and a wrapper for mtrr_bp_init(). Signed-off-by: Juergen Gross <jgross@suse.com> Signed-off-by: Borislav Petkov <bp@suse.de> Link: https://lore.kernel.org/r/20221102074713.21493-13-jgross@suse.com Signed-off-by: Borislav Petkov <bp@suse.de>
2022-07-11x86/setup: Use rng seeds from setup_dataJason A. Donenfeld
Currently, the only way x86 can get an early boot RNG seed is via EFI, which is generally always used now for physical machines, but is very rarely used in VMs, especially VMs that are optimized for starting "instantaneously", such as Firecracker's MicroVM. For tiny fast booting VMs, EFI is not something you generally need or want. Rather, the image loader or firmware should be able to pass a single random seed, exactly as device tree platforms do with the "rng-seed" property. Additionally, this is something that bootloaders can append, with their own seed file management, which is something every other major OS ecosystem has that Linux does not (yet). Add SETUP_RNG_SEED, similar to the other eight setup_data entries that are parsed at boot. It also takes care to zero out the seed immediately after using, in order to retain forward secrecy. This all takes about 7 trivial lines of code. Then, on kexec_file_load(), a new fresh seed is generated and passed to the next kernel, just as is done on device tree architectures when using kexec. And, importantly, I've tested that QEMU is able to properly pass SETUP_RNG_SEED as well, making this work for every step of the way. This code too is pretty straight forward. Together these measures ensure that VMs and nested kexec()'d kernels always receive a proper boot time RNG seed at the earliest possible stage from their parents: - Host [already has strongly initialized RNG] - QEMU [passes fresh seed in SETUP_RNG_SEED field] - Linux [uses parent's seed and gathers entropy of its own] - kexec [passes this in SETUP_RNG_SEED field] - Linux [uses parent's seed and gathers entropy of its own] - kexec [passes this in SETUP_RNG_SEED field] - Linux [uses parent's seed and gathers entropy of its own] - kexec [passes this in SETUP_RNG_SEED field] - ... I've verified in several scenarios that this works quite well from a host kernel to QEMU and down inwards, mixing and matching loaders, with every layer providing a seed to the next. [ bp: Massage commit message. ] Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com> Signed-off-by: Borislav Petkov <bp@suse.de> Acked-by: H. Peter Anvin (Intel) <hpa@zytor.com> Link: https://lore.kernel.org/r/20220630113300.1892799-1-Jason@zx2c4.com
2022-07-01x86/kexec: Carry forward IMA measurement log on kexecJonathan McDowell
On kexec file load, the Integrity Measurement Architecture (IMA) subsystem may verify the IMA signature of the kernel and initramfs, and measure it. The command line parameters passed to the kernel in the kexec call may also be measured by IMA. A remote attestation service can verify a TPM quote based on the TPM event log, the IMA measurement list and the TPM PCR data. This can be achieved only if the IMA measurement log is carried over from the current kernel to the next kernel across the kexec call. PowerPC and ARM64 both achieve this using device tree with a "linux,ima-kexec-buffer" node. x86 platforms generally don't make use of device tree, so use the setup_data mechanism to pass the IMA buffer to the new kernel. Signed-off-by: Jonathan McDowell <noodles@fb.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Mimi Zohar <zohar@linux.ibm.com> # IMA function definitions Link: https://lore.kernel.org/r/YmKyvlF3my1yWTvK@noodles-fedora-PC23Y6EG
2022-06-13x86/mm: Fix RESERVE_BRK() for older binutilsJosh Poimboeuf
With binutils 2.26, RESERVE_BRK() causes a build failure: /tmp/ccnGOKZ5.s: Assembler messages: /tmp/ccnGOKZ5.s:98: Error: missing ')' /tmp/ccnGOKZ5.s:98: Error: missing ')' /tmp/ccnGOKZ5.s:98: Error: missing ')' /tmp/ccnGOKZ5.s:98: Error: junk at end of line, first unrecognized character is `U' The problem is this line: RESERVE_BRK(early_pgt_alloc, INIT_PGT_BUF_SIZE) Specifically, the INIT_PGT_BUF_SIZE macro which (via PAGE_SIZE's use _AC()) has a "1UL", which makes older versions of the assembler unhappy. Unfortunately the _AC() macro doesn't work for inline asm. Inline asm was only needed here to convince the toolchain to add the STT_NOBITS flag. However, if a C variable is placed in a section whose name is prefixed with ".bss", GCC and Clang automatically set STT_NOBITS. In fact, ".bss..page_aligned" already relies on this trick. So fix the build failure (and simplify the macro) by allocating the variable in C. Also, add NOLOAD to the ".brk" output section clause in the linker script. This is a failsafe in case the ".bss" prefix magic trick ever stops working somehow. If there's a section type mismatch, the GNU linker will force the ".brk" output section to be STT_NOBITS. The LLVM linker will fail with a "section type mismatch" error. Note this also changes the name of the variable from .brk.##name to __brk_##name. The variable names aren't actually used anywhere, so it's harmless. Fixes: a1e2c031ec39 ("x86/mm: Simplify RESERVE_BRK()") Reported-by: Joe Damato <jdamato@fastly.com> Reported-by: Byungchul Park <byungchul.park@lge.com> Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Tested-by: Joe Damato <jdamato@fastly.com> Link: https://lore.kernel.org/r/22d07a44c80d8e8e1e82b9a806ddc8c6bbb2606e.1654759036.git.jpoimboe@kernel.org
2022-05-25x86/setup: Use strscpy() to replace deprecated strlcpy()XueBing Chen
strlcpy() is marked deprecated and should not be used, because it doesn't limit the source length. The preferred interface for when strlcpy()'s return value is not checked (truncation) is strscpy(). [ mingo: Tweaked the changelog ] Signed-off-by: XueBing Chen <chenxuebing@jari.cn> Signed-off-by: Ingo Molnar <mingo@kernel.org> Link: https://lore.kernel.org/r/730f0fef.a33.180fa69880f.Coremail.chenxuebing@jari.cn
2022-04-04x86/cpu: Remove "noexec"Borislav Petkov
It doesn't make any sense to disable non-executable mappings - security-wise or else. So rip out that switch and move the remaining code into setup.c and delete setup_nx.c Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Lai Jiangshan <jiangshanlai@gmail.com> Reviewed-by: Kees Cook <keescook@chromium.org> Link: https://lore.kernel.org/r/20220127115626.14179-6-bp@alien8.de
2022-03-23x86/setup: use IS_ENABLED(CONFIG_KEXEC_CORE) instead of #ifdefJisheng Zhang
Replace the conditional compilation using "#ifdef CONFIG_KEXEC_CORE" by a check for "IS_ENABLED(CONFIG_KEXEC_CORE)", to simplify the code and increase compile coverage. Link: https://lkml.kernel.org/r/20211206160514.2000-4-jszhang@kernel.org Signed-off-by: Jisheng Zhang <jszhang@kernel.org> Acked-by: Baoquan He <bhe@redhat.com> Cc: Albert Ou <aou@eecs.berkeley.edu> Cc: Alexandre Ghiti <alex@ghiti.fr> Cc: Borislav Petkov <bp@alien8.de> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Eric W. Biederman <ebiederm@xmission.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Palmer Dabbelt <palmer@dabbelt.com> Cc: Palmer Dabbelt <palmer@rivosinc.com> Cc: Paul Walmsley <paul.walmsley@sifive.com> Cc: Russell King <linux@armlinux.org.uk> Cc: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Deacon <will@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-03-09x86/boot: Fix memremap of setup_indirect structuresRoss Philipson
As documented, the setup_indirect structure is nested inside the setup_data structures in the setup_data list. The code currently accesses the fields inside the setup_indirect structure but only the sizeof(struct setup_data) is being memremapped. No crash occurred but this is just due to how the area is remapped under the covers. Properly memremap both the setup_data and setup_indirect structures in these cases before accessing them. Fixes: b3c72fc9a78e ("x86/boot: Introduce setup_indirect") Signed-off-by: Ross Philipson <ross.philipson@oracle.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com> Cc: <stable@vger.kernel.org> Link: https://lore.kernel.org/r/1645668456-22036-2-git-send-email-ross.philipson@oracle.com
2022-01-10Merge tag 'x86_misc_for_v5.17_rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull misc x86 updates from Borislav Petkov: "The pile which we cannot find the proper topic for so we stick it in x86/misc: - Add support for decoding instructions which do MMIO accesses in order to use it in SEV and TDX guests - An include fix and reorg to allow for removing set_fs in UML later" * tag 'x86_misc_for_v5.17_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/mtrr: Remove the mtrr_bp_init() stub x86/sev-es: Use insn_decode_mmio() for MMIO implementation x86/insn-eval: Introduce insn_decode_mmio() x86/insn-eval: Introduce insn_get_modrm_reg_ptr() x86/insn-eval: Handle insn_get_opcode() failure
2021-12-22x86/mtrr: Remove the mtrr_bp_init() stubChristoph Hellwig
Add an IS_ENABLED() check in setup_arch() and call pat_disable() directly if MTRRs are not supported. This allows to remove the <asm/memtype.h> include in <asm/mtrr.h>, which pull in lowlevel x86 headers that should not be included for UML builds and will cause build warnings with a following patch. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Borislav Petkov <bp@suse.de> Link: https://lore.kernel.org/r/20211215165612.554426-2-hch@lst.de
2021-12-15x86/boot: Move EFI range reservation after cmdline parsingMike Rapoport
The memory reservation in arch/x86/platform/efi/efi.c depends on at least two command line parameters. Put it back later in the boot process and move efi_memblock_x86_reserve_range() out of early_memory_reserve(). An attempt to fix this was done in 8d48bf8206f7 ("x86/boot: Pull up cmdline preparation and early param parsing") but that caused other troubles so it got reverted. The bug this is addressing is: Dan reports that Anjaneya Chagam can no longer use the efi=nosoftreserve kernel command line parameter to suppress "soft reservation" behavior. This is due to the fact that the following call-chain happens at boot: early_reserve_memory |-> efi_memblock_x86_reserve_range |-> efi_fake_memmap_early which does if (!efi_soft_reserve_enabled()) return; and that would have set EFI_MEM_NO_SOFT_RESERVE after having parsed "nosoftreserve". However, parse_early_param() gets called *after* it, leading to the boot cmdline not being taken into account. See also https://lore.kernel.org/r/e8dd8993c38702ee6dd73b3c11f158617e665607.camel@intel.com [ bp: Turn into a proper patch. ] Signed-off-by: Mike Rapoport <rppt@kernel.org> Signed-off-by: Borislav Petkov <bp@suse.de> Link: https://lore.kernel.org/r/20211213112757.2612-4-bp@alien8.de
2021-12-15Revert "x86/boot: Pull up cmdline preparation and early param parsing"Borislav Petkov
This reverts commit 8d48bf8206f77aa8687f0e241e901e5197e52423. It turned out to be a bad idea as it broke supplying mem= cmdline parameters due to parse_memopt() requiring preparatory work like setting up the e820 table in e820__memory_setup() in order to be able to exclude the range specified by mem=. Pulling that up would've broken Xen PV again, see threads at https://lkml.kernel.org/r/20210920120421.29276-1-jgross@suse.com due to xen_memory_setup() needing the first reservations in early_reserve_memory() - kernel and initrd - to have happened already. This could be fixed again by having Xen do those reservations itself... Long story short, revert this and do a simpler fix in a later patch. Signed-off-by: Borislav Petkov <bp@suse.de> Link: https://lore.kernel.org/r/20211213112757.2612-3-bp@alien8.de
2021-12-15Revert "x86/boot: Mark prepare_command_line() __init"Borislav Petkov
This reverts commit c0f2077baa4113f38f008b8e912b9fb3ff8d43df. Signed-off-by: Borislav Petkov <bp@suse.de> Link: https://lore.kernel.org/r/20211213112757.2612-2-bp@alien8.de
2021-11-24x86/boot: Mark prepare_command_line() __initBorislav Petkov
Fix: WARNING: modpost: vmlinux.o(.text.unlikely+0x64d0): Section mismatch in reference \ from the function prepare_command_line() to the variable .init.data:command_line The function prepare_command_line() references the variable __initdata command_line. This is often because prepare_command_line lacks a __initdata annotation or the annotation of command_line is wrong. Apparently some toolchains do different inlining decisions. Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lkml.kernel.org/r/YZySgpmBcNNM2qca@zn.tnic
2021-11-15x86/boot: Pull up cmdline preparation and early param parsingBorislav Petkov
Dan reports that Anjaneya Chagam can no longer use the efi=nosoftreserve kernel command line parameter to suppress "soft reservation" behavior. This is due to the fact that the following call-chain happens at boot: early_reserve_memory |-> efi_memblock_x86_reserve_range |-> efi_fake_memmap_early which does if (!efi_soft_reserve_enabled()) return; and that would have set EFI_MEM_NO_SOFT_RESERVE after having parsed "nosoftreserve". However, parse_early_param() gets called *after* it, leading to the boot cmdline not being taken into account. Therefore, carve out the command line preparation into a separate function which does the early param parsing too. So that it all goes together. And then call that function before early_reserve_memory() so that the params would have been parsed by then. Fixes: 8aa83e6395ce ("x86/setup: Call early_reserve_memory() earlier") Reported-by: Dan Williams <dan.j.williams@intel.com> Reviewed-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Tested-by: Anjaneya Chagam <anjaneya.chagam@intel.com> Cc: <stable@vger.kernel.org> Link: https://lore.kernel.org/r/e8dd8993c38702ee6dd73b3c11f158617e665607.camel@intel.com
2021-11-06memblock: rename memblock_free to memblock_phys_freeMike Rapoport
Since memblock_free() operates on a physical range, make its name reflect it and rename it to memblock_phys_free(), so it will be a logical counterpart to memblock_phys_alloc(). The callers are updated with the below semantic patch: @@ expression addr; expression size; @@ - memblock_free(addr, size); + memblock_phys_free(addr, size); Link: https://lkml.kernel.org/r/20210930185031.18648-6-rppt@kernel.org Signed-off-by: Mike Rapoport <rppt@linux.ibm.com> Cc: Christophe Leroy <christophe.leroy@csgroup.eu> Cc: Juergen Gross <jgross@suse.com> Cc: Shahab Vahedi <Shahab.Vahedi@synopsys.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-09-21x86/setup: Call early_reserve_memory() earlierJuergen Gross
Commit in Fixes introduced early_reserve_memory() to do all needed initial memblock_reserve() calls in one function. Unfortunately, the call of early_reserve_memory() is done too late for Xen dom0, as in some cases a Xen hook called by e820__memory_setup() will need those memory reservations to have happened already. Move the call of early_reserve_memory() before the call of e820__memory_setup() in order to avoid such problems. Fixes: a799c2bd29d1 ("x86/setup: Consolidate early memory reservations") Reported-by: Marek Marczykowski-Górecki <marmarek@invisiblethingslab.com> Signed-off-by: Juergen Gross <jgross@suse.com> Signed-off-by: Borislav Petkov <bp@suse.de> Tested-by: Marek Marczykowski-Górecki <marmarek@invisiblethingslab.com> Tested-by: Nathan Chancellor <nathan@kernel.org> Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/20210920120421.29276-1-jgross@suse.com
2021-09-01x86/setup: Explicitly include acpi.hNathan Chancellor
After commit 342f43af70db ("iscsi_ibft: fix crash due to KASLR physical memory remapping") x86_64_defconfig shows the following errors: arch/x86/kernel/setup.c: In function ‘setup_arch’: arch/x86/kernel/setup.c:916:13: error: implicit declaration of function ‘acpi_mps_check’ [-Werror=implicit-function-declaration] 916 | if (acpi_mps_check()) { | ^~~~~~~~~~~~~~ arch/x86/kernel/setup.c:1110:9: error: implicit declaration of function ‘acpi_table_upgrade’ [-Werror=implicit-function-declaration] 1110 | acpi_table_upgrade(); | ^~~~~~~~~~~~~~~~~~ [... more acpi noise ...] acpi.h was being implicitly included from iscsi_ibft.h in this configuration so the removal of that header means these functions have no definition or declaration. In most other configurations, <linux/acpi.h> continued to be included through at least <linux/tboot.h> if CONFIG_INTEL_TXT was enabled, and there were probably other implicit include paths too. Add acpi.h explicitly so there is no more error, and so that we don't continue to depend on these unreliable implicit include paths. Tested-by: Matthieu Baerts <matthieu.baerts@tessares.net> Signed-off-by: Nathan Chancellor <nathan@kernel.org> Cc: Maurizio Lombardi <mlombard@redhat.com> Cc: Mike Rapoport <rppt@linux.ibm.com> Cc: Konrad Rzeszutek Wilk <konrad@kernel.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-08-31Merge branch 'stable/for-linus-5.15' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/konrad/ibft Pull ibft updates from Konrad Rzeszutek Wilk: "A fix for iBFT parsing code badly interfacing when KASLR is enabled" * 'stable/for-linus-5.15' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/ibft: iscsi_ibft: fix warning in reserve_ibft_region() iscsi_ibft: fix crash due to KASLR physical memory remapping
2021-07-31iscsi_ibft: fix crash due to KASLR physical memory remappingMaurizio Lombardi
Starting with commit a799c2bd29d1 ("x86/setup: Consolidate early memory reservations") memory reservations have been moved earlier during the boot process, before the execution of the Kernel Address Space Layout Randomization code. setup_arch() calls the iscsi_ibft's find_ibft_region() function to find and reserve the memory dedicated to the iBFT and this function also saves a virtual pointer to the iBFT table for later use. The problem is that if KALSR is active, the physical memory gets remapped somewhere else in the virtual address space and the pointer is no longer valid, this will cause a kernel panic when the iscsi driver tries to dereference it. iBFT detected. BUG: unable to handle page fault for address: ffff888000099fd8 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page PGD 0 P4D 0 Oops: 0000 [#1] SMP PTI ..snip.. Call Trace: ? ibft_create_kobject+0x1d2/0x1d2 [iscsi_ibft] do_one_initcall+0x44/0x1d0 ? kmem_cache_alloc_trace+0x119/0x220 do_init_module+0x5c/0x270 __do_sys_init_module+0x12e/0x1b0 do_syscall_64+0x40/0x80 entry_SYSCALL_64_after_hwframe+0x44/0xae Fix this bug by saving the address of the physical location of the ibft; later the driver will use isa_bus_to_virt() to get the correct virtual address. N.B. On each reboot KASLR randomizes the virtual addresses so assuming phys_to_virt before KASLR does its deed is incorrect. Simplify the code by renaming find_ibft_region() to reserve_ibft_region() and remove all the wrappers. Signed-off-by: Maurizio Lombardi <mlombard@redhat.com> Reviewed-by: Mike Rapoport <rppt@linux.ibm.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad@kernel.org>
2021-07-08x86: convert to setup_initial_init_mm()Kefeng Wang
Use setup_initial_init_mm() helper to simplify code. Link: https://lkml.kernel.org/r/20210608083418.137226-16-wangkefeng.wang@huawei.com Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-07-02Merge branch 'akpm' (patches from Andrew)Linus Torvalds
Merge more updates from Andrew Morton: "190 patches. Subsystems affected by this patch series: mm (hugetlb, userfaultfd, vmscan, kconfig, proc, z3fold, zbud, ras, mempolicy, memblock, migration, thp, nommu, kconfig, madvise, memory-hotplug, zswap, zsmalloc, zram, cleanups, kfence, and hmm), procfs, sysctl, misc, core-kernel, lib, lz4, checkpatch, init, kprobes, nilfs2, hfs, signals, exec, kcov, selftests, compress/decompress, and ipc" * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (190 commits) ipc/util.c: use binary search for max_idx ipc/sem.c: use READ_ONCE()/WRITE_ONCE() for use_global_lock ipc: use kmalloc for msg_queue and shmid_kernel ipc sem: use kvmalloc for sem_undo allocation lib/decompressors: remove set but not used variabled 'level' selftests/vm/pkeys: exercise x86 XSAVE init state selftests/vm/pkeys: refill shadow register after implicit kernel write selftests/vm/pkeys: handle negative sys_pkey_alloc() return code selftests/vm/pkeys: fix alloc_random_pkey() to make it really, really random kcov: add __no_sanitize_coverage to fix noinstr for all architectures exec: remove checks in __register_bimfmt() x86: signal: don't do sas_ss_reset() until we are certain that sigframe won't be abandoned hfsplus: report create_date to kstat.btime hfsplus: remove unnecessary oom message nilfs2: remove redundant continue statement in a while-loop kprobes: remove duplicated strong free_insn_page in x86 and s390 init: print out unknown kernel parameters checkpatch: do not complain about positive return values starting with EPOLL checkpatch: improve the indented label test checkpatch: scripts/spdxcheck.py now requires python3 ...
2021-07-01kernel.h: split out panic and oops helpersAndy Shevchenko
kernel.h is being used as a dump for all kinds of stuff for a long time. Here is the attempt to start cleaning it up by splitting out panic and oops helpers. There are several purposes of doing this: - dropping dependency in bug.h - dropping a loop by moving out panic_notifier.h - unload kernel.h from something which has its own domain At the same time convert users tree-wide to use new headers, although for the time being include new header back to kernel.h to avoid twisted indirected includes for existing users. [akpm@linux-foundation.org: thread_info.h needs limits.h] [andriy.shevchenko@linux.intel.com: ia64 fix] Link: https://lkml.kernel.org/r/20210520130557.55277-1-andriy.shevchenko@linux.intel.com Link: https://lkml.kernel.org/r/20210511074137.33666-1-andriy.shevchenko@linux.intel.com Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org> Co-developed-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: Mike Rapoport <rppt@linux.ibm.com> Acked-by: Corey Minyard <cminyard@mvista.com> Acked-by: Christian Brauner <christian.brauner@ubuntu.com> Acked-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Kees Cook <keescook@chromium.org> Acked-by: Wei Liu <wei.liu@kernel.org> Acked-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: Sebastian Reichel <sre@kernel.org> Acked-by: Luis Chamberlain <mcgrof@kernel.org> Acked-by: Stephen Boyd <sboyd@kernel.org> Acked-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Acked-by: Helge Deller <deller@gmx.de> # parisc Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-06-08x86/setup: Document that Windows reserves the first MiBBorislav Petkov
It does so unconditionally too, on Intel and AMD machines, to work around BIOS bugs, as confirmed by Microsoft folks (see Link for full details). Reflow the paragraph, while at it. Signed-off-by: Borislav Petkov <bp@suse.de> Link: https://lkml.kernel.org/r/MWHPR21MB159330952629D36EEDE706B3D7379@MWHPR21MB1593.namprd21.prod.outlook.com
2021-06-07x86/setup: Remove CONFIG_X86_RESERVE_LOW and reservelow= optionsMike Rapoport
The CONFIG_X86_RESERVE_LOW build time and reservelow= command line option allowed to control the amount of memory under 1M that would be reserved at boot to avoid using memory that can be potentially clobbered by BIOS. Since the entire range under 1M is always reserved there is no need for these options anymore and they can be removed. Signed-off-by: Mike Rapoport <rppt@linux.ibm.com> Signed-off-by: Borislav Petkov <bp@suse.de> Link: https://lkml.kernel.org/r/20210601075354.5149-3-rppt@kernel.org
2021-06-03x86/setup: Always reserve the first 1M of RAMMike Rapoport
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 <rppt@linux.ibm.com> Signed-off-by: Borislav Petkov <bp@suse.de> Tested-by: Hugh Dickins <hughd@google.com> Link: https://bugzilla.kernel.org/show_bug.cgi?id=213177 Link: https://lkml.kernel.org/r/20210601075354.5149-2-rppt@kernel.org
2021-05-31x86/thermal: Fix LVT thermal setup for SMI delivery modeBorislav Petkov
There are machines out there with added value crap^WBIOS which provide an SMI handler for the local APIC thermal sensor interrupt. Out of reset, the BSP on those machines has something like 0x200 in that APIC register (timestamps left in because this whole issue is timing sensitive): [ 0.033858] read lvtthmr: 0x330, val: 0x200 which means: - bit 16 - the interrupt mask bit is clear and thus that interrupt is enabled - bits [10:8] have 010b which means SMI delivery mode. Now, later during boot, when the kernel programs the local APIC, it soft-disables it temporarily through the spurious vector register: setup_local_APIC: ... /* * If this comes from kexec/kcrash the APIC might be enabled in * SPIV. Soft disable it before doing further initialization. */ value = apic_read(APIC_SPIV); value &= ~APIC_SPIV_APIC_ENABLED; apic_write(APIC_SPIV, value); which means (from the SDM): "10.4.7.2 Local APIC State After It Has Been Software Disabled ... * The mask bits for all the LVT entries are set. Attempts to reset these bits will be ignored." And this happens too: [ 0.124111] APIC: Switch to symmetric I/O mode setup [ 0.124117] lvtthmr 0x200 before write 0xf to APIC 0xf0 [ 0.124118] lvtthmr 0x10200 after write 0xf to APIC 0xf0 This results in CPU 0 soft lockups depending on the placement in time when the APIC soft-disable happens. Those soft lockups are not 100% reproducible and the reason for that can only be speculated as no one tells you what SMM does. Likely, it confuses the SMM code that the APIC is disabled and the thermal interrupt doesn't doesn't fire at all, leading to CPU 0 stuck in SMM forever... Now, before 4f432e8bb15b ("x86/mce: Get rid of mcheck_intel_therm_init()") due to how the APIC_LVTTHMR was read before APIC initialization in mcheck_intel_therm_init(), it would read the value with the mask bit 16 clear and then intel_init_thermal() would replicate it onto the APs and all would be peachy - the thermal interrupt would remain enabled. But that commit moved that reading to a later moment in intel_init_thermal(), resulting in reading APIC_LVTTHMR on the BSP too late and with its interrupt mask bit set. Thus, revert back to the old behavior of reading the thermal LVT register before the APIC gets initialized. Fixes: 4f432e8bb15b ("x86/mce: Get rid of mcheck_intel_therm_init()") Reported-by: James Feeney <james@nurealm.net> Signed-off-by: Borislav Petkov <bp@suse.de> Cc: <stable@vger.kernel.org> Cc: Zhang Rui <rui.zhang@intel.com> Cc: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com> Link: https://lkml.kernel.org/r/YKIqDdFNaXYd39wz@zn.tnic
2021-04-27Merge tag 'x86_core_for_v5.13' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 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 ...
2021-04-26Merge tag 'x86_cleanups_for_v5.13' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull misc x86 cleanups from Borislav Petkov: "Trivial cleanups and fixes all over the place" * tag 'x86_cleanups_for_v5.13' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: MAINTAINERS: Remove me from IDE/ATAPI section x86/pat: Do not compile stubbed functions when X86_PAT is off x86/asm: Ensure asm/proto.h can be included stand-alone x86/platform/intel/quark: Fix incorrect kernel-doc comment syntax in files x86/msr: Make locally used functions static x86/cacheinfo: Remove unneeded dead-store initialization x86/process/64: Move cpu_current_top_of_stack out of TSS tools/turbostat: Unmark non-kernel-doc comment x86/syscalls: Fix -Wmissing-prototypes warnings from COND_SYSCALL() x86/fpu/math-emu: Fix function cast warning x86/msr: Fix wr/rdmsr_safe_regs_on_cpu() prototypes x86: Fix various typos in comments, take #2 x86: Remove unusual Unicode characters from comments x86/kaslr: Return boolean values from a function returning bool x86: Fix various typos in comments x86/setup: Remove unused RESERVE_BRK_ARRAY() stacktrace: Move documentation for arch_stack_walk_reliable() to header x86: Remove duplicate TSC DEADLINE MSR definitions
2021-04-26Merge tag 'x86_boot_for_v5.13' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 boot updates from Borislav Petkov: "Consolidation and cleanup of the early memory reservations, along with a couple of gcc11 warning fixes" * tag 'x86_boot_for_v5.13' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/setup: Move trim_snb_memory() later in setup_arch() to fix boot hangs x86/setup: Merge several reservations of start of memory x86/setup: Consolidate early memory reservations x86/boot/compressed: Avoid gcc-11 -Wstringop-overread warning x86/boot/tboot: Avoid Wstringop-overread-warning
2021-04-14x86/setup: Move trim_snb_memory() later in setup_arch() to fix boot hangsMike Rapoport
Commit a799c2bd29d1 ("x86/setup: Consolidate early memory reservations") moved reservation of the memory inaccessible by Sandy Bride integrated graphics very early, and, as a result, on systems with such devices the first 1M was reserved by trim_snb_memory() which prevented the allocation of the real mode trampoline and made the boot hang very early. Since the purpose of trim_snb_memory() is to prevent problematic pages ever reaching the graphics device, it is safe to reserve these pages after memblock allocations are possible. Move trim_snb_memory() later in boot so that it will be called after reserve_real_mode() and make comments describing trim_snb_memory() operation more elaborate. [ bp: Massage a bit. ] Fixes: a799c2bd29d1 ("x86/setup: Consolidate early memory reservations") Reported-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Mike Rapoport <rppt@linux.ibm.com> Signed-off-by: Borislav Petkov <bp@suse.de> Tested-by: Randy Dunlap <rdunlap@infradead.org> Tested-by: Hugh Dickins <hughd@google.com> Link: https://lkml.kernel.org/r/f67d3e03-af90-f790-baf4-8d412fe055af@infradead.org
2021-04-13ACPI: x86: Call acpi_boot_table_init() after acpi_table_upgrade()Rafael J. Wysocki
Commit 1a1c130ab757 ("ACPI: tables: x86: Reserve memory occupied by ACPI tables") attempted to address an issue with reserving the memory occupied by ACPI tables, but it broke the initrd-based table override mechanism relied on by multiple users. To restore the initrd-based ACPI table override functionality, move the acpi_boot_table_init() invocation in setup_arch() on x86 after the acpi_table_upgrade() one. Fixes: 1a1c130ab757 ("ACPI: tables: x86: Reserve memory occupied by ACPI tables") Reported-by: Hans de Goede <hdegoede@redhat.com> Tested-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>