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2024-10-27Merge tag 'x86_urgent_for_v6.12_rc5' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 fixes from Borislav Petkov: - Prevent a certain range of pages which get marked as hypervisor-only, to get allocated to a CoCo (SNP) guest which cannot use them and thus fail booting - Fix the microcode loader on AMD to pay attention to the stepping of a patch and to handle the case where a BIOS config option splits the machine into logical NUMA nodes per L3 cache slice - Disable LAM from being built by default due to security concerns * tag 'x86_urgent_for_v6.12_rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/sev: Ensure that RMP table fixups are reserved x86/microcode/AMD: Split load_microcode_amd() x86/microcode/AMD: Pay attention to the stepping dynamically x86/lam: Disable ADDRESS_MASKING in most cases
2024-10-25x86: fix whitespace in runtime-const assembler outputLinus Torvalds
The x86 user pointer validation changes made me look at compiler output a lot, and the wrong indentation for the ".popsection" in the generated assembler triggered me. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2024-10-25x86: fix user address masking non-canonical speculation issueLinus Torvalds
It turns out that AMD has a "Meltdown Lite(tm)" issue with non-canonical accesses in kernel space. And so using just the high bit to decide whether an access is in user space or kernel space ends up with the good old "leak speculative data" if you have the right gadget using the result: CVE-2020-12965 “Transient Execution of Non-Canonical Accesses“ Now, the kernel surrounds the access with a STAC/CLAC pair, and those instructions end up serializing execution on older Zen architectures, which closes the speculation window. But that was true only up until Zen 5, which renames the AC bit [1]. That improves performance of STAC/CLAC a lot, but also means that the speculation window is now open. Note that this affects not just the new address masking, but also the regular valid_user_address() check used by access_ok(), and the asm version of the sign bit check in the get_user() helpers. It does not affect put_user() or clear_user() variants, since there's no speculative result to be used in a gadget for those operations. Reported-by: Andrew Cooper <andrew.cooper3@citrix.com> Link: https://lore.kernel.org/all/80d94591-1297-4afb-b510-c665efd37f10@citrix.com/ Link: https://lore.kernel.org/all/20241023094448.GAZxjFkEOOF_DM83TQ@fat_crate.local/ [1] Link: https://www.amd.com/en/resources/product-security/bulletin/amd-sb-1010.html Link: https://arxiv.org/pdf/2108.10771 Cc: Josh Poimboeuf <jpoimboe@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Tested-by: Maciej Wieczor-Retman <maciej.wieczor-retman@intel.com> # LAM case Fixes: 2865baf54077 ("x86: support user address masking instead of non-speculative conditional") Fixes: 6014bc27561f ("x86-64: make access_ok() independent of LAM") Fixes: b19b74bc99b1 ("x86/mm: Rework address range check in get_user() and put_user()") Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2024-10-24Merge tag 'bpf-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpfLinus Torvalds
Pull bpf fixes from Daniel Borkmann: - Fix an out-of-bounds read in bpf_link_show_fdinfo for BPF sockmap link file descriptors (Hou Tao) - Fix BPF arm64 JIT's address emission with tag-based KASAN enabled reserving not enough size (Peter Collingbourne) - Fix BPF verifier do_misc_fixups patching for inlining of the bpf_get_branch_snapshot BPF helper (Andrii Nakryiko) - Fix a BPF verifier bug and reject BPF program write attempts into read-only marked BPF maps (Daniel Borkmann) - Fix perf_event_detach_bpf_prog error handling by removing an invalid check which would skip BPF program release (Jiri Olsa) - Fix memory leak when parsing mount options for the BPF filesystem (Hou Tao) * tag 'bpf-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf: bpf: Check validity of link->type in bpf_link_show_fdinfo() bpf: Add the missing BPF_LINK_TYPE invocation for sockmap bpf: fix do_misc_fixups() for bpf_get_branch_snapshot() bpf,perf: Fix perf_event_detach_bpf_prog error handling selftests/bpf: Add test for passing in uninit mtu_len selftests/bpf: Add test for writes to .rodata bpf: Remove MEM_UNINIT from skb/xdp MTU helpers bpf: Fix overloading of MEM_UNINIT's meaning bpf: Add MEM_WRITE attribute bpf: Preserve param->string when parsing mount options bpf, arm64: Fix address emission with tag-based KASAN enabled
2024-10-24Merge tag 'loongarch-fixes-6.12-1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson Pull LoongArch fixes from Huacai Chen: "Get correct cores_per_package for SMT systems, enable IRQ if do_ale() triggered in irq-enabled context, and fix some bugs about vDSO, memory managenent, hrtimer in KVM, etc" * tag 'loongarch-fixes-6.12-1' of git://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson: LoongArch: KVM: Mark hrtimer to expire in hard interrupt context LoongArch: Make KASAN usable for variable cpu_vabits LoongArch: Set initial pte entry with PAGE_GLOBAL for kernel space LoongArch: Don't crash in stack_top() for tasks without vDSO LoongArch: Set correct size for vDSO code mapping LoongArch: Enable IRQ if do_ale() triggered in irq-enabled context LoongArch: Get correct cores_per_package for SMT systems LoongArch: Use "Exception return address" to comment ERA
2024-10-23LoongArch: KVM: Mark hrtimer to expire in hard interrupt contextHuacai Chen
Like commit 2c0d278f3293f ("KVM: LAPIC: Mark hrtimer to expire in hard interrupt context") and commit 9090825fa9974 ("KVM: arm/arm64: Let the timer expire in hardirq context on RT"), On PREEMPT_RT enabled kernels unmarked hrtimers are moved into soft interrupt expiry mode by default. Then the timers are canceled from an preempt-notifier which is invoked with disabled preemption which is not allowed on PREEMPT_RT. The timer callback is short so in could be invoked in hard-IRQ context. So let the timer expire on hard-IRQ context even on -RT. This fix a "scheduling while atomic" bug for PREEMPT_RT enabled kernels: BUG: scheduling while atomic: qemu-system-loo/1011/0x00000002 Modules linked in: amdgpu rfkill nft_fib_inet nft_fib_ipv4 nft_fib_ipv6 nft_fib nft_reject_inet nf_reject_ipv4 nf_reject_ipv6 nft_reject nft_ct nft_chain_nat ns CPU: 1 UID: 0 PID: 1011 Comm: qemu-system-loo Tainted: G W 6.12.0-rc2+ #1774 Tainted: [W]=WARN Hardware name: Loongson Loongson-3A5000-7A1000-1w-CRB/Loongson-LS3A5000-7A1000-1w-CRB, BIOS vUDK2018-LoongArch-V2.0.0-prebeta9 10/21/2022 Stack : ffffffffffffffff 0000000000000000 9000000004e3ea38 9000000116744000 90000001167475a0 0000000000000000 90000001167475a8 9000000005644830 90000000058dc000 90000000058dbff8 9000000116747420 0000000000000001 0000000000000001 6a613fc938313980 000000000790c000 90000001001c1140 00000000000003fe 0000000000000001 000000000000000d 0000000000000003 0000000000000030 00000000000003f3 000000000790c000 9000000116747830 90000000057ef000 0000000000000000 9000000005644830 0000000000000004 0000000000000000 90000000057f4b58 0000000000000001 9000000116747868 900000000451b600 9000000005644830 9000000003a13998 0000000010000020 00000000000000b0 0000000000000004 0000000000000000 0000000000071c1d ... Call Trace: [<9000000003a13998>] show_stack+0x38/0x180 [<9000000004e3ea34>] dump_stack_lvl+0x84/0xc0 [<9000000003a71708>] __schedule_bug+0x48/0x60 [<9000000004e45734>] __schedule+0x1114/0x1660 [<9000000004e46040>] schedule_rtlock+0x20/0x60 [<9000000004e4e330>] rtlock_slowlock_locked+0x3f0/0x10a0 [<9000000004e4f038>] rt_spin_lock+0x58/0x80 [<9000000003b02d68>] hrtimer_cancel_wait_running+0x68/0xc0 [<9000000003b02e30>] hrtimer_cancel+0x70/0x80 [<ffff80000235eb70>] kvm_restore_timer+0x50/0x1a0 [kvm] [<ffff8000023616c8>] kvm_arch_vcpu_load+0x68/0x2a0 [kvm] [<ffff80000234c2d4>] kvm_sched_in+0x34/0x60 [kvm] [<9000000003a749a0>] finish_task_switch.isra.0+0x140/0x2e0 [<9000000004e44a70>] __schedule+0x450/0x1660 [<9000000004e45cb0>] schedule+0x30/0x180 [<ffff800002354c70>] kvm_vcpu_block+0x70/0x120 [kvm] [<ffff800002354d80>] kvm_vcpu_halt+0x60/0x3e0 [kvm] [<ffff80000235b194>] kvm_handle_gspr+0x3f4/0x4e0 [kvm] [<ffff80000235f548>] kvm_handle_exit+0x1c8/0x260 [kvm] Reviewed-by: Bibo Mao <maobibo@loongson.cn> Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2024-10-23LoongArch: Make KASAN usable for variable cpu_vabitsHuacai Chen
Currently, KASAN on LoongArch assume the CPU VA bits is 48, which is true for Loongson-3 series, but not for Loongson-2 series (only 40 or lower), this patch fix that issue and make KASAN usable for variable cpu_vabits. Solution is very simple: Just define XRANGE_SHADOW_SHIFT which means valid address length from VA_BITS to min(cpu_vabits, VA_BITS). Cc: stable@vger.kernel.org Signed-off-by: Kanglong Wang <wangkanglong@loongson.cn> Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2024-10-23x86/sev: Ensure that RMP table fixups are reservedAshish Kalra
The BIOS reserves RMP table memory via e820 reservations. This can still lead to RMP page faults during kexec if the host tries to access memory within the same 2MB region. Commit 400fea4b9651 ("x86/sev: Add callback to apply RMP table fixups for kexec" adjusts the e820 reservations for the RMP table so that the entire 2MB range at the start/end of the RMP table is marked reserved. The e820 reservations are then passed to firmware via SNP_INIT where they get marked HV-Fixed. The RMP table fixups are done after the e820 ranges have been added to memblock, allowing the fixup ranges to still be allocated and used by the system. The problem is that this memory range is now marked reserved in the e820 tables and during SNP initialization these reserved ranges are marked as HV-Fixed. This means that the pages cannot be used by an SNP guest, only by the hypervisor. However, the memory management subsystem does not make this distinction and can allocate one of those pages to an SNP guest. This will ultimately result in RMPUPDATE failures associated with the guest, causing it to fail to start or terminate when accessing the HV-Fixed page. The issue is captured below with memblock=debug: [ 0.000000] SEV-SNP: *** DEBUG: snp_probe_rmptable_info:352 - rmp_base=0x280d4800000, rmp_end=0x28357efffff ... [ 0.000000] BIOS-provided physical RAM map: ... [ 0.000000] BIOS-e820: [mem 0x00000280d4800000-0x0000028357efffff] reserved [ 0.000000] BIOS-e820: [mem 0x0000028357f00000-0x0000028357ffffff] usable ... ... [ 0.183593] memblock add: [0x0000028357f00000-0x0000028357ffffff] e820__memblock_setup+0x74/0xb0 ... [ 0.203179] MEMBLOCK configuration: [ 0.207057] memory size = 0x0000027d0d194000 reserved size = 0x0000000009ed2c00 [ 0.215299] memory.cnt = 0xb ... [ 0.311192] memory[0x9] [0x0000028357f00000-0x0000028357ffffff], 0x0000000000100000 bytes flags: 0x0 ... ... [ 0.419110] SEV-SNP: Reserving start/end of RMP table on a 2MB boundary [0x0000028357e00000] [ 0.428514] e820: update [mem 0x28357e00000-0x28357ffffff] usable ==> reserved [ 0.428517] e820: update [mem 0x28357e00000-0x28357ffffff] usable ==> reserved [ 0.428520] e820: update [mem 0x28357e00000-0x28357ffffff] usable ==> reserved ... ... [ 5.604051] MEMBLOCK configuration: [ 5.607922] memory size = 0x0000027d0d194000 reserved size = 0x0000000011faae02 [ 5.616163] memory.cnt = 0xe ... [ 5.754525] memory[0xc] [0x0000028357f00000-0x0000028357ffffff], 0x0000000000100000 bytes on node 0 flags: 0x0 ... ... [ 10.080295] Early memory node ranges[ 10.168065] ... node 0: [mem 0x0000028357f00000-0x0000028357ffffff] ... ... [ 8149.348948] SEV-SNP: RMPUPDATE failed for PFN 28357f7c, pg_level: 1, ret: 2 As shown above, the memblock allocations show 1MB after the end of the RMP as available for allocation, which is what the RMP table fixups have reserved. This memory range subsequently gets allocated as SNP guest memory, resulting in an RMPUPDATE failure. This can potentially be fixed by not reserving the memory range in the e820 table, but that causes kexec failures when using the KEXEC_FILE_LOAD syscall. The solution is to use memblock_reserve() to mark the memory reserved for the system, ensuring that it cannot be allocated to an SNP guest. Since HV-Fixed memory is still readable/writable by the host, this only ends up being a problem if the memory in this range requires a page state change, which generally will only happen when allocating memory in this range to be used for running SNP guests, which is now possible with the SNP hypervisor support in kernel 6.11. Backporter note: Fixes tag points to a 6.9 change but as the last paragraph above explains, this whole thing can happen after 6.11 received SNP HV support, therefore backporting to 6.9 is not really necessary. [ bp: Massage commit message. ] Fixes: 400fea4b9651 ("x86/sev: Add callback to apply RMP table fixups for kexec") Suggested-by: Thomas Lendacky <thomas.lendacky@amd.com> Signed-off-by: Ashish Kalra <ashish.kalra@amd.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Tom Lendacky <thomas.lendacky@amd.com> Cc: <stable@kernel.org> # 6.11, see Backporter note above. Link: https://lore.kernel.org/r/20240815221630.131133-1-Ashish.Kalra@amd.com
2024-10-22x86/microcode/AMD: Split load_microcode_amd()Borislav Petkov (AMD)
This function should've been split a long time ago because it is used in two paths: 1) On the late loading path, when the microcode is loaded through the request_firmware interface 2) In the save_microcode_in_initrd() path which collects all the microcode patches which are relevant for the current system before the initrd with the microcode container has been jettisoned. In that path, it is not really necessary to iterate over the nodes on a system and match a patch however it didn't cause any trouble so it was left for a later cleanup However, that later cleanup was expedited by the fact that Jens was enabling "Use L3 as a NUMA node" in the BIOS setting in his machine and so this causes the NUMA CPU masks used in cpumask_of_node() to be generated *after* 2) above happened on the first node. Which means, all those masks were funky, wrong, uninitialized and whatnot, leading to explosions when dereffing c->microcode in load_microcode_amd(). So split that function and do only the necessary work needed at each stage. Fixes: 94838d230a6c ("x86/microcode/AMD: Use the family,model,stepping encoded in the patch ID") Reported-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Tested-by: Jens Axboe <axboe@kernel.dk> Link: https://lore.kernel.org/r/91194406-3fdf-4e38-9838-d334af538f74@kernel.dk
2024-10-22x86/microcode/AMD: Pay attention to the stepping dynamicallyBorislav Petkov (AMD)
Commit in Fixes changed how a microcode patch is loaded on Zen and newer but the patch matching needs to happen with different rigidity, depending on what is being done: 1) When the patch is added to the patches cache, the stepping must be ignored because the driver still supports different steppings per system 2) When the patch is matched for loading, then the stepping must be taken into account because each CPU needs the patch matching its exact stepping Take care of that by making the matching smarter. Fixes: 94838d230a6c ("x86/microcode/AMD: Use the family,model,stepping encoded in the patch ID") Reported-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Tested-by: Jens Axboe <axboe@kernel.dk> Link: https://lore.kernel.org/r/91194406-3fdf-4e38-9838-d334af538f74@kernel.dk
2024-10-21x86/lam: Disable ADDRESS_MASKING in most casesPawan Gupta
Linear Address Masking (LAM) has a weakness related to transient execution as described in the SLAM paper[1]. Unless Linear Address Space Separation (LASS) is enabled this weakness may be exploitable. Until kernel adds support for LASS[2], only allow LAM for COMPILE_TEST, or when speculation mitigations have been disabled at compile time, otherwise keep LAM disabled. There are no processors in market that support LAM yet, so currently nobody is affected by this issue. [1] SLAM: https://download.vusec.net/papers/slam_sp24.pdf [2] LASS: https://lore.kernel.org/lkml/20230609183632.48706-1-alexander.shishkin@linux.intel.com/ [ dhansen: update SPECULATION_MITIGATIONS -> CPU_MITIGATIONS ] Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Reviewed-by: Sohil Mehta <sohil.mehta@intel.com> Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc:stable@vger.kernel.org Link: https://lore.kernel.org/all/5373262886f2783f054256babdf5a98545dc986b.1706068222.git.pawan.kumar.gupta%40linux.intel.com
2024-10-21Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds
Pull kvm fixes from Paolo Bonzini: "ARM64: - Fix the guest view of the ID registers, making the relevant fields writable from userspace (affecting ID_AA64DFR0_EL1 and ID_AA64PFR1_EL1) - Correcly expose S1PIE to guests, fixing a regression introduced in 6.12-rc1 with the S1POE support - Fix the recycling of stage-2 shadow MMUs by tracking the context (are we allowed to block or not) as well as the recycling state - Address a couple of issues with the vgic when userspace misconfigures the emulation, resulting in various splats. Headaches courtesy of our Syzkaller friends - Stop wasting space in the HYP idmap, as we are dangerously close to the 4kB limit, and this has already exploded in -next - Fix another race in vgic_init() - Fix a UBSAN error when faking the cache topology with MTE enabled RISCV: - RISCV: KVM: use raw_spinlock for critical section in imsic x86: - A bandaid for lack of XCR0 setup in selftests, which causes trouble if the compiler is configured to have x86-64-v3 (with AVX) as the default ISA. Proper XCR0 setup will come in the next merge window. - Fix an issue where KVM would not ignore low bits of the nested CR3 and potentially leak up to 31 bytes out of the guest memory's bounds - Fix case in which an out-of-date cached value for the segments could by returned by KVM_GET_SREGS. - More cleanups for KVM_X86_QUIRK_SLOT_ZAP_ALL - Override MTRR state for KVM confidential guests, making it WB by default as is already the case for Hyper-V guests. Generic: - Remove a couple of unused functions" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (27 commits) RISCV: KVM: use raw_spinlock for critical section in imsic KVM: selftests: Fix out-of-bounds reads in CPUID test's array lookups KVM: selftests: x86: Avoid using SSE/AVX instructions KVM: nSVM: Ignore nCR3[4:0] when loading PDPTEs from memory KVM: VMX: reset the segment cache after segment init in vmx_vcpu_reset() KVM: x86: Clean up documentation for KVM_X86_QUIRK_SLOT_ZAP_ALL KVM: x86/mmu: Add lockdep assert to enforce safe usage of kvm_unmap_gfn_range() KVM: x86/mmu: Zap only SPs that shadow gPTEs when deleting memslot x86/kvm: Override default caching mode for SEV-SNP and TDX KVM: Remove unused kvm_vcpu_gfn_to_pfn_atomic KVM: Remove unused kvm_vcpu_gfn_to_pfn KVM: arm64: Ensure vgic_ready() is ordered against MMIO registration KVM: arm64: vgic: Don't check for vgic_ready() when setting NR_IRQS KVM: arm64: Fix shift-out-of-bounds bug KVM: arm64: Shave a few bytes from the EL2 idmap code KVM: arm64: Don't eagerly teardown the vgic on init error KVM: arm64: Expose S1PIE to guests KVM: arm64: nv: Clarify safety of allowing TLBI unmaps to reschedule KVM: arm64: nv: Punt stage-2 recycling to a vCPU request KVM: arm64: nv: Do not block when unmapping stage-2 if disallowed ...
2024-10-21LoongArch: Set initial pte entry with PAGE_GLOBAL for kernel spaceBibo Mao
There are two pages in one TLB entry on LoongArch system. For kernel space, it requires both two pte entries (buddies) with PAGE_GLOBAL bit set, otherwise HW treats it as non-global tlb, there will be potential problems if tlb entry for kernel space is not global. Such as fail to flush kernel tlb with the function local_flush_tlb_kernel_range() which supposed only flush tlb with global bit. Kernel address space areas include percpu, vmalloc, vmemmap, fixmap and kasan areas. For these areas both two consecutive page table entries should be enabled with PAGE_GLOBAL bit. So with function set_pte() and pte_clear(), pte buddy entry is checked and set besides its own pte entry. However it is not atomic operation to set both two pte entries, there is problem with test_vmalloc test case. So function kernel_pte_init() is added to init a pte table when it is created for kernel address space, and the default initial pte value is PAGE_GLOBAL rather than zero at beginning. Then only its own pte entry need update with function set_pte() and pte_clear(), nothing to do with the pte buddy entry. Signed-off-by: Bibo Mao <maobibo@loongson.cn> Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2024-10-21LoongArch: Don't crash in stack_top() for tasks without vDSOThomas Weißschuh
Not all tasks have a vDSO mapped, for example kthreads never do. If such a task ever ends up calling stack_top(), it will derefence the NULL vdso pointer and crash. This can for example happen when using kunit: [<9000000000203874>] stack_top+0x58/0xa8 [<90000000002956cc>] arch_pick_mmap_layout+0x164/0x220 [<90000000003c284c>] kunit_vm_mmap_init+0x108/0x12c [<90000000003c1fbc>] __kunit_add_resource+0x38/0x8c [<90000000003c2704>] kunit_vm_mmap+0x88/0xc8 [<9000000000410b14>] usercopy_test_init+0xbc/0x25c [<90000000003c1db4>] kunit_try_run_case+0x5c/0x184 [<90000000003c3d54>] kunit_generic_run_threadfn_adapter+0x24/0x48 [<900000000022e4bc>] kthread+0xc8/0xd4 [<9000000000200ce8>] ret_from_kernel_thread+0xc/0xa4 Fixes: 803b0fc5c3f2 ("LoongArch: Add process management") Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de> Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2024-10-21LoongArch: Set correct size for vDSO code mappingHuacai Chen
The current size of vDSO code mapping is hardcoded to PAGE_SIZE. This cannot work for 4KB page size after commit 18efd0b10e0fd77 ("LoongArch: vDSO: Wire up getrandom() vDSO implementation") because the code size increases to 8KB. Thus set the code mapping size to its real size, i.e. PAGE_ALIGN(vdso_end - vdso_start). Fixes: 18efd0b10e0fd77 ("LoongArch: vDSO: Wire up getrandom() vDSO implementation") Reviewed-by: Xi Ruoyao <xry111@xry111.site> Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2024-10-21LoongArch: Enable IRQ if do_ale() triggered in irq-enabled contextHuacai Chen
Unaligned access exception can be triggered in irq-enabled context such as user mode, in this case do_ale() may call get_user() which may cause sleep. Then we will get: BUG: sleeping function called from invalid context at arch/loongarch/kernel/access-helper.h:7 in_atomic(): 0, irqs_disabled(): 1, non_block: 0, pid: 129, name: modprobe preempt_count: 0, expected: 0 RCU nest depth: 0, expected: 0 CPU: 0 UID: 0 PID: 129 Comm: modprobe Tainted: G W 6.12.0-rc1+ #1723 Tainted: [W]=WARN Stack : 9000000105e0bd48 0000000000000000 9000000003803944 9000000105e08000 9000000105e0bc70 9000000105e0bc78 0000000000000000 0000000000000000 9000000105e0bc78 0000000000000001 9000000185e0ba07 9000000105e0b890 ffffffffffffffff 9000000105e0bc78 73924b81763be05b 9000000100194500 000000000000020c 000000000000000a 0000000000000000 0000000000000003 00000000000023f0 00000000000e1401 00000000072f8000 0000007ffbb0e260 0000000000000000 0000000000000000 9000000005437650 90000000055d5000 0000000000000000 0000000000000003 0000007ffbb0e1f0 0000000000000000 0000005567b00490 0000000000000000 9000000003803964 0000007ffbb0dfec 00000000000000b0 0000000000000007 0000000000000003 0000000000071c1d ... Call Trace: [<9000000003803964>] show_stack+0x64/0x1a0 [<9000000004c57464>] dump_stack_lvl+0x74/0xb0 [<9000000003861ab4>] __might_resched+0x154/0x1a0 [<900000000380c96c>] emulate_load_store_insn+0x6c/0xf60 [<9000000004c58118>] do_ale+0x78/0x180 [<9000000003801bc8>] handle_ale+0x128/0x1e0 So enable IRQ if unaligned access exception is triggered in irq-enabled context to fix it. Cc: stable@vger.kernel.org Reported-by: Binbin Zhou <zhoubinbin@loongson.cn> Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2024-10-21LoongArch: Get correct cores_per_package for SMT systemsHuacai Chen
In loongson_sysconf, The "core" of cores_per_node and cores_per_package stands for a logical core, which means in a SMT system it stands for a thread indeed. This information is gotten from SMBIOS Type4 Structure, so in order to get a correct cores_per_package for both SMT and non-SMT systems in parse_cpu_table() we should use SMBIOS_THREAD_PACKAGE_OFFSET instead of SMBIOS_CORE_PACKAGE_OFFSET. Cc: stable@vger.kernel.org Reported-by: Chao Li <lichao@loongson.cn> Tested-by: Chao Li <lichao@loongson.cn> Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2024-10-21LoongArch: Use "Exception return address" to comment ERAYanteng Si
The information contained in the comment for LOONGARCH_CSR_ERA is even less informative than the macro itself, which can cause confusion for junior developers. Let's use the full English term. Signed-off-by: Yanteng Si <siyanteng@cqsoftware.com.cn> Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2024-10-21bpf, arm64: Fix address emission with tag-based KASAN enabledPeter Collingbourne
When BPF_TRAMP_F_CALL_ORIG is enabled, the address of a bpf_tramp_image struct on the stack is passed during the size calculation pass and an address on the heap is passed during code generation. This may cause a heap buffer overflow if the heap address is tagged because emit_a64_mov_i64() will emit longer code than it did during the size calculation pass. The same problem could occur without tag-based KASAN if one of the 16-bit words of the stack address happened to be all-ones during the size calculation pass. Fix the problem by assuming the worst case (4 instructions) when calculating the size of the bpf_tramp_image address emission. Fixes: 19d3c179a377 ("bpf, arm64: Fix trampoline for BPF_TRAMP_F_CALL_ORIG") Signed-off-by: Peter Collingbourne <pcc@google.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Xu Kuohai <xukuohai@huawei.com> Link: https://linux-review.googlesource.com/id/I1496f2bc24fba7a1d492e16e2b94cf43714f2d3c Link: https://lore.kernel.org/bpf/20241018221644.3240898-1-pcc@google.com
2024-10-20Merge tag 'x86_urgent_for_v6.12_rc4' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 fixes from Borislav Petkov: - Explicitly disable the TSC deadline timer when going idle to address some CPU errata in that area - Do not apply the Zenbleed fix on anything else except AMD Zen2 on the late microcode loading path - Clear CPU buffers later in the NMI exit path on 32-bit to avoid register clearing while they still contain sensitive data, for the RDFS mitigation - Do not clobber EFLAGS.ZF with VERW on the opportunistic SYSRET exit path on 32-bit - Fix parsing issues of memory bandwidth specification in sysfs for resctrl's memory bandwidth allocation feature - Other small cleanups and improvements * tag 'x86_urgent_for_v6.12_rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/apic: Always explicitly disarm TSC-deadline timer x86/CPU/AMD: Only apply Zenbleed fix for Zen2 during late microcode load x86/bugs: Use code segment selector for VERW operand x86/entry_32: Clear CPU buffers after register restore in NMI return x86/entry_32: Do not clobber user EFLAGS.ZF x86/resctrl: Annotate get_mem_config() functions as __init x86/resctrl: Avoid overflow in MB settings in bw_validate() x86/amd_nb: Add new PCI ID for AMD family 1Ah model 20h
2024-10-20Merge tag 'kvmarm-fixes-6.12-3' of ↵Paolo Bonzini
git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD KVM/arm64 fixes for 6.12, take #3 - Stop wasting space in the HYP idmap, as we are dangerously close to the 4kB limit, and this has already exploded in -next - Fix another race in vgic_init() - Fix a UBSAN error when faking the cache topology with MTE enabled
2024-10-20Merge tag 'kvmarm-fixes-6.12-2' of ↵Paolo Bonzini
git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD KVM/arm64 fixes for 6.12, take #2 - Fix the guest view of the ID registers, making the relevant fields writable from userspace (affecting ID_AA64DFR0_EL1 and ID_AA64PFR1_EL1) - Correcly expose S1PIE to guests, fixing a regression introduced in 6.12-rc1 with the S1POE support - Fix the recycling of stage-2 shadow MMUs by tracking the context (are we allowed to block or not) as well as the recycling state - Address a couple of issues with the vgic when userspace misconfigures the emulation, resulting in various splats. Headaches courtesy of our Syzkaller friends
2024-10-20RISCV: KVM: use raw_spinlock for critical section in imsicCyan Yang
For the external interrupt updating procedure in imsic, there was a spinlock to protect it already. But since it should not be preempted in any cases, we should turn to use raw_spinlock to prevent any preemption in case PREEMPT_RT was enabled. Signed-off-by: Cyan Yang <cyan.yang@sifive.com> Reviewed-by: Yong-Xuan Wang <yongxuan.wang@sifive.com> Reviewed-by: Anup Patel <anup@brainfault.org> Message-ID: <20240919160126.44487-1-cyan.yang@sifive.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2024-10-20KVM: nSVM: Ignore nCR3[4:0] when loading PDPTEs from memorySean Christopherson
Ignore nCR3[4:0] when loading PDPTEs from memory for nested SVM, as bits 4:0 of CR3 are ignored when PAE paging is used, and thus VMRUN doesn't enforce 32-byte alignment of nCR3. In the absolute worst case scenario, failure to ignore bits 4:0 can result in an out-of-bounds read, e.g. if the target page is at the end of a memslot, and the VMM isn't using guard pages. Per the APM: The CR3 register points to the base address of the page-directory-pointer table. The page-directory-pointer table is aligned on a 32-byte boundary, with the low 5 address bits 4:0 assumed to be 0. And the SDM's much more explicit: 4:0 Ignored Note, KVM gets this right when loading PDPTRs, it's only the nSVM flow that is broken. Fixes: e4e517b4be01 ("KVM: MMU: Do not unconditionally read PDPTE from guest memory") Reported-by: Kirk Swidowski <swidowski@google.com> Cc: Andy Nguyen <theflow@google.com> Cc: 3pvd <3pvd@google.com> Cc: stable@vger.kernel.org Signed-off-by: Sean Christopherson <seanjc@google.com> Message-ID: <20241009140838.1036226-1-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2024-10-20KVM: VMX: reset the segment cache after segment init in vmx_vcpu_reset()Maxim Levitsky
Reset the segment cache after segment initialization in vmx_vcpu_reset() to harden KVM against caching stale/uninitialized data. Without the recent fix to bypass the cache in kvm_arch_vcpu_put(), the following scenario is possible: - vCPU is just created, and the vCPU thread is preempted before SS.AR_BYTES is written in vmx_vcpu_reset(). - When scheduling out the vCPU task, kvm_arch_vcpu_in_kernel() => vmx_get_cpl() reads and caches '0' for SS.AR_BYTES. - vmx_vcpu_reset() => seg_setup() configures SS.AR_BYTES, but doesn't invoke vmx_segment_cache_clear() to invalidate the cache. As a result, KVM retains a stale value in the cache, which can be read, e.g. via KVM_GET_SREGS. Usually this is not a problem because the VMX segment cache is reset on each VM-Exit, but if the userspace VMM (e.g KVM selftests) reads and writes system registers just after the vCPU was created, _without_ modifying SS.AR_BYTES, userspace will write back the stale '0' value and ultimately will trigger a VM-Entry failure due to incorrect SS segment type. Invalidating the cache after writing the VMCS doesn't address the general issue of cache accesses from IRQ context being unsafe, but it does prevent KVM from clobbering the VMCS, i.e. mitigates the harm done _if_ KVM has a bug that results in an unsafe cache access. Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com> Fixes: 2fb92db1ec08 ("KVM: VMX: Cache vmcs segment fields") [sean: rework changelog to account for previous patch] Signed-off-by: Sean Christopherson <seanjc@google.com> Message-ID: <20241009175002.1118178-3-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2024-10-20KVM: x86/mmu: Add lockdep assert to enforce safe usage of kvm_unmap_gfn_range()Sean Christopherson
Add a lockdep assertion in kvm_unmap_gfn_range() to ensure that either mmu_invalidate_in_progress is elevated, or that the range is being zapped due to memslot removal (loosely detected by slots_lock being held). Zapping SPTEs without mmu_invalidate_{in_progress,seq} protection is unsafe as KVM's page fault path snapshots state before acquiring mmu_lock, and thus can create SPTEs with stale information if vCPUs aren't forced to retry faults (due to seeing an in-progress or past MMU invalidation). Memslot removal is a special case, as the memslot is retrieved outside of mmu_invalidate_seq, i.e. doesn't use the "standard" protections, and instead relies on SRCU synchronization to ensure any in-flight page faults are fully resolved before zapping SPTEs. Signed-off-by: Sean Christopherson <seanjc@google.com> Message-ID: <20241009192345.1148353-3-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2024-10-20KVM: x86/mmu: Zap only SPs that shadow gPTEs when deleting memslotSean Christopherson
When performing a targeted zap on memslot removal, zap only MMU pages that shadow guest PTEs, as zapping all SPs that "match" the gfn is inexact and unnecessary. Furthermore, for_each_gfn_valid_sp() arguably shouldn't exist, because it doesn't do what most people would it expect it to do. The "round gfn for level" adjustment that is done for direct SPs (no gPTE) means that the exact gfn comparison will not get a match, even when a SP does "cover" a gfn, or was even created specifically for a gfn. For memslot deletion specifically, KVM's behavior will vary significantly based on the size and alignment of a memslot, and in weird ways. E.g. for a 4KiB memslot, KVM will zap more SPs if the slot is 1GiB aligned than if it's only 4KiB aligned. And as described below, zapping SPs in the aligned case overzaps for direct MMUs, as odds are good the upper-level SPs are serving other memslots. To iterate over all potentially-relevant gfns, KVM would need to make a pass over the hash table for each level, with the gfn used for lookup rounded for said level. And then check that the SP is of the correct level, too, e.g. to avoid over-zapping. But even then, KVM would massively overzap, as processing every level is all but guaranteed to zap SPs that serve other memslots, especially if the memslot being removed is relatively small. KVM could mitigate that issue by processing only levels that can be possible guest huge pages, i.e. are less likely to be re-used for other memslot, but while somewhat logical, that's quite arbitrary and would be a bit of a mess to implement. So, zap only SPs with gPTEs, as the resulting behavior is easy to describe, is predictable, and is explicitly minimal, i.e. KVM only zaps SPs that absolutely must be zapped. Cc: Yan Zhao <yan.y.zhao@intel.com> Signed-off-by: Sean Christopherson <seanjc@google.com> Reviewed-by: Yan Zhao <yan.y.zhao@intel.com> Tested-by: Yan Zhao <yan.y.zhao@intel.com> Message-ID: <20241009192345.1148353-2-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2024-10-20x86/kvm: Override default caching mode for SEV-SNP and TDXKirill A. Shutemov
AMD SEV-SNP and Intel TDX have limited access to MTRR: either it is not advertised in CPUID or it cannot be programmed (on TDX, due to #VE on CR0.CD clear). This results in guests using uncached mappings where it shouldn't and pmd/pud_set_huge() failures due to non-uniform memory type reported by mtrr_type_lookup(). Override MTRR state, making it WB by default as the kernel does for Hyper-V guests. Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Suggested-by: Binbin Wu <binbin.wu@intel.com> Cc: Juergen Gross <jgross@suse.com> Cc: Tom Lendacky <thomas.lendacky@amd.com> Reviewed-by: Juergen Gross <jgross@suse.com> Message-ID: <20241015095818.357915-1-kirill.shutemov@linux.intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2024-10-19Merge tag 'rust-fixes-6.12-2' of https://github.com/Rust-for-Linux/linuxLinus Torvalds
Pull rust fixes from Miguel Ojeda: "Toolchain and infrastructure: - Fix several issues with the 'rustc-option' macro. It includes a refactor from Masahiro of three '{cc,rust}-*' macros, which is not a fix but avoids repeating the same commands (which would be several lines in the case of 'rustc-option'). - Fix conditions for 'CONFIG_HAVE_CFI_ICALL_NORMALIZE_INTEGERS'. It includes the addition of 'CONFIG_RUSTC_LLVM_VERSION', which is not a fix but is needed for the actual fix. And a trivial grammar fix" * tag 'rust-fixes-6.12-2' of https://github.com/Rust-for-Linux/linux: cfi: fix conditions for HAVE_CFI_ICALL_NORMALIZE_INTEGERS kbuild: rust: add `CONFIG_RUSTC_LLVM_VERSION` kbuild: fix issues with rustc-option kbuild: refactor cc-option-yn, cc-disable-warning, rust-option-yn macros lib/Kconfig.debug: fix grammar in RUST_BUILD_ASSERT_ALLOW
2024-10-18Merge tag 'bpf-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpfLinus Torvalds
Pull bpf fixes from Daniel Borkmann: - Fix BPF verifier to not affect subreg_def marks in its range propagation (Eduard Zingerman) - Fix a truncation bug in the BPF verifier's handling of coerce_reg_to_size_sx (Dimitar Kanaliev) - Fix the BPF verifier's delta propagation between linked registers under 32-bit addition (Daniel Borkmann) - Fix a NULL pointer dereference in BPF devmap due to missing rxq information (Florian Kauer) - Fix a memory leak in bpf_core_apply (Jiri Olsa) - Fix an UBSAN-reported array-index-out-of-bounds in BTF parsing for arrays of nested structs (Hou Tao) - Fix build ID fetching where memory areas backing the file were created with memfd_secret (Andrii Nakryiko) - Fix BPF task iterator tid filtering which was incorrectly using pid instead of tid (Jordan Rome) - Several fixes for BPF sockmap and BPF sockhash redirection in combination with vsocks (Michal Luczaj) - Fix riscv BPF JIT and make BPF_CMPXCHG fully ordered (Andrea Parri) - Fix riscv BPF JIT under CONFIG_CFI_CLANG to prevent the possibility of an infinite BPF tailcall (Pu Lehui) - Fix a build warning from resolve_btfids that bpf_lsm_key_free cannot be resolved (Thomas Weißschuh) - Fix a bug in kfunc BTF caching for modules where the wrong BTF object was returned (Toke Høiland-Jørgensen) - Fix a BPF selftest compilation error in cgroup-related tests with musl libc (Tony Ambardar) - Several fixes to BPF link info dumps to fill missing fields (Tyrone Wu) - Add BPF selftests for kfuncs from multiple modules, checking that the correct kfuncs are called (Simon Sundberg) - Ensure that internal and user-facing bpf_redirect flags don't overlap (Toke Høiland-Jørgensen) - Switch to use kvzmalloc to allocate BPF verifier environment (Rik van Riel) - Use raw_spinlock_t in BPF ringbuf to fix a sleep in atomic splat under RT (Wander Lairson Costa) * tag 'bpf-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf: (38 commits) lib/buildid: Handle memfd_secret() files in build_id_parse() selftests/bpf: Add test case for delta propagation bpf: Fix print_reg_state's constant scalar dump bpf: Fix incorrect delta propagation between linked registers bpf: Properly test iter/task tid filtering bpf: Fix iter/task tid filtering riscv, bpf: Make BPF_CMPXCHG fully ordered bpf, vsock: Drop static vsock_bpf_prot initialization vsock: Update msg_count on read_skb() vsock: Update rx_bytes on read_skb() bpf, sockmap: SK_DROP on attempted redirects of unsupported af_vsock selftests/bpf: Add asserts for netfilter link info bpf: Fix link info netfilter flags to populate defrag flag selftests/bpf: Add test for sign extension in coerce_subreg_to_size_sx() selftests/bpf: Add test for truncation after sign extension in coerce_reg_to_size_sx() bpf: Fix truncation bug in coerce_reg_to_size_sx() selftests/bpf: Assert link info uprobe_multi count & path_size if unset bpf: Fix unpopulated path_size when uprobe_multi fields unset selftests/bpf: Fix cross-compiling urandom_read selftests/bpf: Add test for kfunc module order ...
2024-10-18Merge tag 'powerpc-6.12-5' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux Pull powerpc fix from Madhavan Srinivasan: - To prevent possible memory leak, free "name" on error in opal_event_init() Thanks to Michael Ellerman and 2639161967. * tag 'powerpc-6.12-5' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: powerpc/powernv: Free name on error in opal_event_init()
2024-10-18Merge tag 's390-6.12-3' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux Pull s390 fixes from Heiko Carstens: - Fix PCI error recovery by handling error events correctly - Fix CCA crypto card behavior within protected execution environment - Two KVM commits which fix virtual vs physical address handling bugs in KVM pfault handling - Fix return code handling in pckmo_key2protkey() - Deactivate sclp console as late as possible so that outstanding messages appear on the console instead of being dropped on reboot - Convert newlines to CRLF instead of LFCR for the sclp vt220 driver, as required by the vt220 specification - Initialize also psw mask in perf_arch_fetch_caller_regs() to make sure that user_mode(regs) will return false - Update defconfigs * tag 's390-6.12-3' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: s390: Update defconfigs s390: Initialize psw mask in perf_arch_fetch_caller_regs() s390/sclp_vt220: Convert newlines to CRLF instead of LFCR s390/sclp: Deactivate sclp after all its users s390/pkey_pckmo: Return with success for valid protected key types KVM: s390: Change virtual to physical address access in diag 0x258 handler KVM: s390: gaccess: Check if guest address is in memslot s390/ap: Fix CCA crypto card behavior within protected execution environment s390/pci: Handle PCI error codes other than 0x3a
2024-10-17Merge tag 'x86_bugs_post_ibpb' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 IBPB fixes from Borislav Petkov: "This fixes the IBPB implementation of older AMDs (< gen4) that do not flush the RSB (Return Address Stack) so you can still do some leaking when using a "=ibpb" mitigation for Retbleed or SRSO. Fix it by doing the flushing in software on those generations. IBPB is not the default setting so this is not likely to affect anybody in practice" * tag 'x86_bugs_post_ibpb' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/bugs: Do not use UNTRAIN_RET with IBPB on entry x86/bugs: Skip RSB fill at VMEXIT x86/entry: Have entry_ibpb() invalidate return predictions x86/cpufeatures: Add a IBPB_NO_RET BUG flag x86/cpufeatures: Define X86_FEATURE_AMD_IBPB_RET
2024-10-17Merge tag 'arm64-fixes' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux Pull arm64 fixes from Will Deacon: - Disable software tag-based KASAN when compiling with GCC, as functions are incorrectly instrumented leading to a crash early during boot - Fix pkey configuration for kernel threads when POE is enabled - Fix invalid memory accesses in uprobes when targetting load-literal instructions * tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: kasan: Disable Software Tag-Based KASAN with GCC Documentation/protection-keys: add AArch64 to documentation arm64: set POR_EL0 for kernel threads arm64: probes: Fix uprobes for big-endian kernels arm64: probes: Fix simulate_ldr*_literal() arm64: probes: Remove broken LDR (literal) uprobe support
2024-10-17Merge tag 'arm-fixes-6.12' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc Pull SoC fixes from Arnd Bergmann: "Most of the fixes this time are for platform specific drivers, addressing issues found through build testing on freescale, ep93xx, starfive, and npcm platforms, as as well as the ffa firmware. The fixes for the scmi firmware driver address compatibility problems found on broadcom machines. There are only two devicetree fixes, addressing incorrect in configuration on broadcom and marvell machines. The changes to the Documentation and MAINTAINERS files are for clarification only" * tag 'arm-fixes-6.12' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc: firmware: arm_ffa: Avoid string-fortify warning caused by memcpy() firmware: arm_scmi: Queue in scmi layer for mailbox implementation firmware: arm_ffa: Avoid string-fortify warning in export_uuid() firmware: arm_scmi: Give SMC transport precedence over mailbox firmware: arm_scmi: Fix the double free in scmi_debugfs_common_setup() Documentation/process: maintainer-soc: clarify submitting patches dmaengine: cirrus: check that output may be truncated dmaengine: cirrus: ERR_CAST() ioremap error MAINTAINERS: use the canonical soc mailing list address and mark it as L: ARM: dts: bcm2837-rpi-cm3-io3: Fix HDMI hpd-gpio pin arm64: dts: marvell: cn9130-sr-som: fix cp0 mdio pin numbers soc: fsl: cpm1: qmc: Fix unused data compilation warning soc: fsl: cpm1: qmc: Do not use IS_ERR_VALUE() on error pointers reset: starfive: jh71x0: Fix accessing the empty member on JH7110 SoC reset: npcm: convert comma to semicolon
2024-10-17riscv, bpf: Make BPF_CMPXCHG fully orderedAndrea Parri
According to the prototype formal BPF memory consistency model discussed e.g. in [1] and following the ordering properties of the C/in-kernel macro atomic_cmpxchg(), a BPF atomic operation with the BPF_CMPXCHG modifier is fully ordered. However, the current RISC-V JIT lowerings fail to meet such memory ordering property. This is illustrated by the following litmus test: BPF BPF__MP+success_cmpxchg+fence { 0:r1=x; 0:r3=y; 0:r5=1; 1:r2=y; 1:r4=f; 1:r7=x; } P0 | P1 ; *(u64 *)(r1 + 0) = 1 | r1 = *(u64 *)(r2 + 0) ; r2 = cmpxchg_64 (r3 + 0, r4, r5) | r3 = atomic_fetch_add((u64 *)(r4 + 0), r5) ; | r6 = *(u64 *)(r7 + 0) ; exists (1:r1=1 /\ 1:r6=0) whose "exists" clause is not satisfiable according to the BPF memory model. Using the current RISC-V JIT lowerings, the test can be mapped to the following RISC-V litmus test: RISCV RISCV__MP+success_cmpxchg+fence { 0:x1=x; 0:x3=y; 0:x5=1; 1:x2=y; 1:x4=f; 1:x7=x; } P0 | P1 ; sd x5, 0(x1) | ld x1, 0(x2) ; L00: | amoadd.d.aqrl x3, x5, 0(x4) ; lr.d x2, 0(x3) | ld x6, 0(x7) ; bne x2, x4, L01 | ; sc.d x6, x5, 0(x3) | ; bne x6, x4, L00 | ; fence rw, rw | ; L01: | ; exists (1:x1=1 /\ 1:x6=0) where the two stores in P0 can be reordered. Update the RISC-V JIT lowerings/implementation of BPF_CMPXCHG to emit an SC with RELEASE ("rl") annotation in order to meet the expected memory ordering guarantees. The resulting RISC-V JIT lowerings of BPF_CMPXCHG match the RISC-V lowerings of the C atomic_cmpxchg(). Other lowerings were fixed via 20a759df3bba ("riscv, bpf: make some atomic operations fully ordered"). Fixes: dd642ccb45ec ("riscv, bpf: Implement more atomic operations for RV64") Signed-off-by: Andrea Parri <parri.andrea@gmail.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Reviewed-by: Puranjay Mohan <puranjay@kernel.org> Acked-by: Björn Töpel <bjorn@kernel.org> Link: https://lpc.events/event/18/contributions/1949/attachments/1665/3441/bpfmemmodel.2024.09.19p.pdf [1] Link: https://lore.kernel.org/bpf/20241017143628.2673894-1-parri.andrea@gmail.com
2024-10-17KVM: arm64: Ensure vgic_ready() is ordered against MMIO registrationOliver Upton
kvm_vgic_map_resources() prematurely marks the distributor as 'ready', potentially allowing vCPUs to enter the guest before the distributor's MMIO registration has been made visible. Plug the race by marking the distributor as ready only after MMIO registration is completed. Rely on the implied ordering of synchronize_srcu() to ensure the MMIO registration is visible before vgic_dist::ready. This also means that writers to vgic_dist::ready are now serialized by the slots_lock, which was effectively the case already as all writers held the slots_lock in addition to the config_lock. Fixes: 59112e9c390b ("KVM: arm64: vgic: Fix a circular locking issue") Signed-off-by: Oliver Upton <oliver.upton@linux.dev> Link: https://lore.kernel.org/r/20241017001947.2707312-3-oliver.upton@linux.dev Signed-off-by: Marc Zyngier <maz@kernel.org>
2024-10-17KVM: arm64: vgic: Don't check for vgic_ready() when setting NR_IRQSOliver Upton
KVM commits to a particular sizing of SPIs when the vgic is initialized, which is before the point a vgic becomes ready. On top of that, KVM supplies a default amount of SPIs should userspace not explicitly configure this. As such, the check for vgic_ready() in the handling of KVM_DEV_ARM_VGIC_GRP_NR_IRQS is completely wrong, and testing if nr_spis is nonzero is sufficient for preventing userspace from playing games with us. Signed-off-by: Oliver Upton <oliver.upton@linux.dev> Link: https://lore.kernel.org/r/20241017001947.2707312-2-oliver.upton@linux.dev Signed-off-by: Marc Zyngier <maz@kernel.org>
2024-10-17KVM: arm64: Fix shift-out-of-bounds bugIlkka Koskinen
Fix a shift-out-of-bounds bug reported by UBSAN when running VM with MTE enabled host kernel. UBSAN: shift-out-of-bounds in arch/arm64/kvm/sys_regs.c:1988:14 shift exponent 33 is too large for 32-bit type 'int' CPU: 26 UID: 0 PID: 7629 Comm: qemu-kvm Not tainted 6.12.0-rc2 #34 Hardware name: IEI NF5280R7/Mitchell MB, BIOS 00.00. 2024-10-12 09:28:54 10/14/2024 Call trace: dump_backtrace+0xa0/0x128 show_stack+0x20/0x38 dump_stack_lvl+0x74/0x90 dump_stack+0x18/0x28 __ubsan_handle_shift_out_of_bounds+0xf8/0x1e0 reset_clidr+0x10c/0x1c8 kvm_reset_sys_regs+0x50/0x1c8 kvm_reset_vcpu+0xec/0x2b0 __kvm_vcpu_set_target+0x84/0x158 kvm_vcpu_set_target+0x138/0x168 kvm_arch_vcpu_ioctl_vcpu_init+0x40/0x2b0 kvm_arch_vcpu_ioctl+0x28c/0x4b8 kvm_vcpu_ioctl+0x4bc/0x7a8 __arm64_sys_ioctl+0xb4/0x100 invoke_syscall+0x70/0x100 el0_svc_common.constprop.0+0x48/0xf0 do_el0_svc+0x24/0x38 el0_svc+0x3c/0x158 el0t_64_sync_handler+0x120/0x130 el0t_64_sync+0x194/0x198 Fixes: 7af0c2534f4c ("KVM: arm64: Normalize cache configuration") Cc: stable@vger.kernel.org Reviewed-by: Gavin Shan <gshan@redhat.com> Signed-off-by: Ilkka Koskinen <ilkka@os.amperecomputing.com> Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com> Link: https://lore.kernel.org/r/20241017025701.67936-1-ilkka@os.amperecomputing.com Signed-off-by: Marc Zyngier <maz@kernel.org>
2024-10-17KVM: arm64: Shave a few bytes from the EL2 idmap codeMarc Zyngier
Our idmap is becoming too big, to the point where it doesn't fit in a 4kB page anymore. There are some low-hanging fruits though, such as the el2_init_state horror that is expanded 3 times in the kernel. Let's at least limit ourselves to two copies, which makes the kernel link again. At some point, we'll have to have a better way of doing this. Reported-by: Nathan Chancellor <nathan@kernel.org> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20241009204903.GA3353168@thelio-3990X
2024-10-16s390: Update defconfigsHeiko Carstens
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2024-10-16s390: Initialize psw mask in perf_arch_fetch_caller_regs()Heiko Carstens
Also initialize regs->psw.mask in perf_arch_fetch_caller_regs(). This way user_mode(regs) will return false, like it should. It looks like all current users initialize regs to zero, so that this doesn't fix a bug currently. However it is better to not rely on callers to do this. Fixes: 914d52e46490 ("s390: implement perf_arch_fetch_caller_regs") Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2024-10-16powerpc/powernv: Free name on error in opal_event_init()Michael Ellerman
In opal_event_init() if request_irq() fails name is not freed, leading to a memory leak. The code only runs at boot time, there's no way for a user to trigger it, so there's no security impact. Fix the leak by freeing name in the error path. Reported-by: 2639161967 <2639161967@qq.com> Closes: https://lore.kernel.org/linuxppc-dev/87wmjp3wig.fsf@mail.lhotse Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://patch.msgid.link/20240920093520.67997-1-mpe@ellerman.id.au
2024-10-15Merge tag 'mvebu-fixes-6.12-1' of ↵Arnd Bergmann
https://git.kernel.org/pub/scm/linux/kernel/git/gclement/mvebu into arm/fixes mvebu fixes for 6.12 (part 1) Fix cp0 mdio pin numbers on SolidRun CN9130 SoM * tag 'mvebu-fixes-6.12-1' of https://git.kernel.org/pub/scm/linux/kernel/git/gclement/mvebu: arm64: dts: marvell: cn9130-sr-som: fix cp0 mdio pin numbers Link: https://lore.kernel.org/r/87ldyud25o.fsf@BLaptop.bootlin.com Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2024-10-15x86/apic: Always explicitly disarm TSC-deadline timerZhang Rui
New processors have become pickier about the local APIC timer state before entering low power modes. These low power modes are used (for example) when you close your laptop lid and suspend. If you put your laptop in a bag and it is not in this low power mode, it is likely to get quite toasty while it quickly sucks the battery dry. The problem boils down to some CPUs' inability to power down until the CPU recognizes that the local APIC timer is shut down. The current kernel code works in one-shot and periodic modes but does not work for deadline mode. Deadline mode has been the supported and preferred mode on Intel CPUs for over a decade and uses an MSR to drive the timer instead of an APIC register. Disable the TSC Deadline timer in lapic_timer_shutdown() by writing to MSR_IA32_TSC_DEADLINE when in TSC-deadline mode. Also avoid writing to the initial-count register (APIC_TMICT) which is ignored in TSC-deadline mode. Note: The APIC_LVTT|=APIC_LVT_MASKED operation should theoretically be enough to tell the hardware that the timer will not fire in any of the timer modes. But mitigating AMD erratum 411[1] also requires clearing out APIC_TMICT. Solely setting APIC_LVT_MASKED is also ineffective in practice on Intel Lunar Lake systems, which is the motivation for this change. 1. 411 Processor May Exit Message-Triggered C1E State Without an Interrupt if Local APIC Timer Reaches Zero - https://www.amd.com/content/dam/amd/en/documents/archived-tech-docs/revision-guides/41322_10h_Rev_Gd.pdf Fixes: 279f1461432c ("x86: apic: Use tsc deadline for oneshot when available") Suggested-by: Dave Hansen <dave.hansen@intel.com> Signed-off-by: Zhang Rui <rui.zhang@intel.com> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Tested-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com> Tested-by: Todd Brandt <todd.e.brandt@intel.com> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/all/20241015061522.25288-1-rui.zhang%40intel.com
2024-10-14arm64: set POR_EL0 for kernel threadsJoey Gouly
Restrict kernel threads to only have RWX overlays for pkey 0. This matches what arch/x86 does, by defaulting to a restrictive PKRU. Signed-off-by: Joey Gouly <joey.gouly@arm.com> Cc: Will Deacon <will@kernel.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Reviewed-by: Kevin Brodsky <Kevin.Brodsky@arm.com> Link: https://lore.kernel.org/r/20241001133618.1547996-2-joey.gouly@arm.com Signed-off-by: Will Deacon <will@kernel.org>
2024-10-13cfi: fix conditions for HAVE_CFI_ICALL_NORMALIZE_INTEGERSAlice Ryhl
The HAVE_CFI_ICALL_NORMALIZE_INTEGERS option has some tricky conditions when KASAN or GCOV are turned on, as in that case we need some clang and rustc fixes [1][2] to avoid boot failures. The intent with the current setup is that you should be able to override the check and turn on the option if your clang/rustc has the fix. However, this override does not work in practice. Thus, use the new RUSTC_LLVM_VERSION to correctly implement the check for whether the fix is available. Additionally, remove KASAN_HW_TAGS from the list of incompatible options. The CFI_ICALL_NORMALIZE_INTEGERS option is incompatible with KASAN because LLVM will emit some constructors when using KASAN that are assigned incorrect CFI tags. These constructors are emitted due to use of -fsanitize=kernel-address or -fsanitize=kernel-hwaddress that are respectively passed when KASAN_GENERIC or KASAN_SW_TAGS are enabled. However, the KASAN_HW_TAGS option relies on hardware support for MTE instead and does not pass either flag. (Note also that KASAN_HW_TAGS does not `select CONSTRUCTORS`.) Link: https://github.com/llvm/llvm-project/pull/104826 [1] Link: https://github.com/rust-lang/rust/pull/129373 [2] Fixes: 4c66f8307ac0 ("cfi: encode cfi normalized integers + kasan/gcov bug in Kconfig") Signed-off-by: Alice Ryhl <aliceryhl@google.com> Reviewed-by: Sami Tolvanen <samitolvanen@google.com> Link: https://lore.kernel.org/r/20241010-icall-detect-vers-v1-2-8f114956aa88@google.com Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2024-10-12Merge tag 'powerpc-6.12-4' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux Pull powerpc fix from Michael Ellerman: - Fix crash in memcpy on 8xx due to dcbz workaround since recent changes Thanks to Christophe Leroy. * tag 'powerpc-6.12-4' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: powerpc/8xx: Fix kernel DTLB miss on dcbz
2024-10-11Merge tag 'for-linus-6.12a-rc3-tag' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip Pull xen fix from Juergen Gross: "A fix for topology information of Xen PV guests" * tag 'for-linus-6.12a-rc3-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: x86/xen: mark boot CPU of PV guest in MSR_IA32_APICBASE
2024-10-11x86/CPU/AMD: Only apply Zenbleed fix for Zen2 during late microcode loadJohn Allen
Commit f69759be251d ("x86/CPU/AMD: Move Zenbleed check to the Zen2 init function") causes a bit in the DE_CFG MSR to get set erroneously after a microcode late load. The microcode late load path calls into amd_check_microcode() and subsequently zen2_zenbleed_check(). Since the above commit removes the cpu_has_amd_erratum() call from zen2_zenbleed_check(), this will cause all non-Zen2 CPUs to go through the function and set the bit in the DE_CFG MSR. Call into the Zenbleed fix path on Zen2 CPUs only. [ bp: Massage commit message, use cpu_feature_enabled(). ] Fixes: f69759be251d ("x86/CPU/AMD: Move Zenbleed check to the Zen2 init function") Signed-off-by: John Allen <john.allen@amd.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Acked-by: Borislav Petkov (AMD) <bp@alien8.de> Cc: <stable@vger.kernel.org> Link: https://lore.kernel.org/r/20240923164404.27227-1-john.allen@amd.com