Intel OpenBMC Linux kernel source tree (mirror) https://git.radix-linux.su/BMC/Intel-BMC/linux.git/atom?h=dev-4.6 2016-04-21T17:34:23+00:00 2016-04-21T17:34:23+00:00 Dave Martin Dave.Martin@arm.com 2016-04-18T17:57:26+00:00 urn:sha1:882416c1e4d1c9d4c7b50e0f5c3fa9ef043cd710 When using the Virtualisation Host Extensions, EL1 is not used in the host and requires no separate configuration. In addition, with VHE enabled, non-hyp-specific EL2 configuration that does not need to be done early will be done anyway in __cpu_setup via the _EL1 system register aliases. In particular, the layout and definition of CPTR_EL2 are changed by enabling VHE so that they resemble CPACR_EL1, so existing code to initialise CPTR_EL2 becomes architecturally wrong in this case. This patch simply skips the affected initialisation code in the non-VHE case. Signed-off-by: Dave Martin <Dave.Martin@arm.com> Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> 2016-04-18T15:23:24+00:00 Ard Biesheuvel ard.biesheuvel@linaro.org 2016-04-15T10:11:21+00:00 urn:sha1:adb4907007445ab9d392f4ce398cd7fa5d26612b In head.S, the str_l macro, which takes a source register, a symbol name and a temp register, is used to store a status value to the variable __early_cpu_boot_status. Subsequently, the value of the temp register is reused to invalidate any cachelines covering this variable. However, since str_l resolves to adrp \tmp, \sym str \src, [\tmp, :lo12:\sym] the temp register never actually holds the address of the variable but only of the 4 KB window that covers it, and reusing it leads to the wrong cacheline being invalidated. So instead, take the address explicitly before doing the store, and reuse that value to perform the cache invalidation. Fixes: bb9052744f4b ("arm64: Handle early CPU boot failures") Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Acked-by: Mark Rutland <mark.rutland@arm.com> Acked-by: Suzuki K Poulose <Suzuki.Poulose@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> 2016-03-25T02:13:59+00:00 Linus Torvalds torvalds@linux-foundation.org 2016-03-25T02:13:59+00:00 urn:sha1:9d854607f9005c593dca9672b708f28e6ef96fe4 Pull second set of arm64 updates from Catalin Marinas: - KASLR bug fixes: use callee-saved register, boot-time I-cache maintenance - inv_entry asm macro fix (EL0 check typo) - pr_notice("Virtual kernel memory layout...") splitting - Clean-ups: use p?d_set_huge consistently, allow preemption around copy_to_user_page, remove unused __local_flush_icache_all() * tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: arm64: mm: allow preemption in copy_to_user_page arm64: consistently use p?d_set_huge arm64: kaslr: use callee saved register to preserve SCTLR across C call arm64: Split pr_notice("Virtual kernel memory layout...") into multiple pr_cont() arm64: drop unused __local_flush_icache_all() arm64: fix KASLR boot-time I-cache maintenance arm64/kernel: fix incorrect EL0 check in inv_entry macro 2016-03-24T16:19:24+00:00 Ard Biesheuvel ard.biesheuvel@linaro.org 2016-03-21T17:35:11+00:00 urn:sha1:d5e5743797adc26e09db262e7a4b6b81d8c0f45c The KASLR code incorrectly expects the contents of x18 to be preserved across a call into C code, and uses it to stash the contents of SCTLR_EL1 before enabling the MMU. If the MMU needs to be disabled again to create the randomized kernel mapping, x18 is written back to SCTLR_EL1, which is likely to crash the system if x18 has been clobbered by kasan_early_init() or kaslr_early_init(). So use x22 instead, which is not in use so far in head.S Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> 2016-03-21T12:08:50+00:00 Mark Rutland mark.rutland@arm.com 2016-03-15T11:22:57+00:00 urn:sha1:b90b4a608ea2401cc491828f7a385edd2e236e37 Commit f80fb3a3d50843a4 ("arm64: add support for kernel ASLR") missed a DSB necessary to complete I-cache maintenance in the primary boot path, and hence stale instructions may still be present in the I-cache and may be executed until the I-cache maintenance naturally completes. Since commit 8ec41987436d566f ("arm64: mm: ensure patched kernel text is fetched from PoU"), all CPUs invalidate their I-caches after their MMU is enabled. Prior a CPU's MMU having been enabled, arbitrary lines may have been fetched from the PoC into I-caches. We never patch text expected to be executed with the MMU off. Thus, it is unnecessary to perform broadcast I-cache maintenance in the primary boot path. This patch reduces the scope of the I-cache maintenance to the local CPU, and adds the missing DSB with similar scope, matching prior maintenance in the primary boot path. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Acked-by: Ard Biesehvuel <ard.biesheuvel@linaro.org> Cc: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> 2016-03-18T03:03:47+00:00 Linus Torvalds torvalds@linux-foundation.org 2016-03-18T03:03:47+00:00 urn:sha1:588ab3f9afdfa1a6b1e5761c858b2c4ab6098285 Pull arm64 updates from Catalin Marinas: "Here are the main arm64 updates for 4.6. There are some relatively intrusive changes to support KASLR, the reworking of the kernel virtual memory layout and initial page table creation. Summary: - Initial page table creation reworked to avoid breaking large block mappings (huge pages) into smaller ones. The ARM architecture requires break-before-make in such cases to avoid TLB conflicts but that's not always possible on live page tables - Kernel virtual memory layout: the kernel image is no longer linked to the bottom of the linear mapping (PAGE_OFFSET) but at the bottom of the vmalloc space, allowing the kernel to be loaded (nearly) anywhere in physical RAM - Kernel ASLR: position independent kernel Image and modules being randomly mapped in the vmalloc space with the randomness is provided by UEFI (efi_get_random_bytes() patches merged via the arm64 tree, acked by Matt Fleming) - Implement relative exception tables for arm64, required by KASLR (initial code for ARCH_HAS_RELATIVE_EXTABLE added to lib/extable.c but actual x86 conversion to deferred to 4.7 because of the merge dependencies) - Support for the User Access Override feature of ARMv8.2: this allows uaccess functions (get_user etc.) to be implemented using LDTR/STTR instructions. Such instructions, when run by the kernel, perform unprivileged accesses adding an extra level of protection. The set_fs() macro is used to "upgrade" such instruction to privileged accesses via the UAO bit - Half-precision floating point support (part of ARMv8.2) - Optimisations for CPUs with or without a hardware prefetcher (using run-time code patching) - copy_page performance improvement to deal with 128 bytes at a time - Sanity checks on the CPU capabilities (via CPUID) to prevent incompatible secondary CPUs from being brought up (e.g. weird big.LITTLE configurations) - valid_user_regs() reworked for better sanity check of the sigcontext information (restored pstate information) - ACPI parking protocol implementation - CONFIG_DEBUG_RODATA enabled by default - VDSO code marked as read-only - DEBUG_PAGEALLOC support - ARCH_HAS_UBSAN_SANITIZE_ALL enabled - Erratum workaround Cavium ThunderX SoC - set_pte_at() fix for PROT_NONE mappings - Code clean-ups" * tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (99 commits) arm64: kasan: Fix zero shadow mapping overriding kernel image shadow arm64: kasan: Use actual memory node when populating the kernel image shadow arm64: Update PTE_RDONLY in set_pte_at() for PROT_NONE permission arm64: Fix misspellings in comments. arm64: efi: add missing frame pointer assignment arm64: make mrs_s prefixing implicit in read_cpuid arm64: enable CONFIG_DEBUG_RODATA by default arm64: Rework valid_user_regs arm64: mm: check at build time that PAGE_OFFSET divides the VA space evenly arm64: KVM: Move kvm_call_hyp back to its original localtion arm64: mm: treat memstart_addr as a signed quantity arm64: mm: list kernel sections in order arm64: lse: deal with clobbered IP registers after branch via PLT arm64: mm: dump: Use VA_START directly instead of private LOWEST_ADDR arm64: kconfig: add submenu for 8.2 architectural features arm64: kernel: acpi: fix ioremap in ACPI parking protocol cpu_postboot arm64: Add support for Half precision floating point arm64: Remove fixmap include fragility arm64: Add workaround for Cavium erratum 27456 arm64: mm: Mark .rodata as RO ... 2016-02-29T18:34:18+00:00 Marc Zyngier marc.zyngier@arm.com 2014-02-19T09:33:14+00:00 urn:sha1:1f364c8c48a0767885a18451ee074c64b454157a With ARMv8.1 VHE, the architecture is able to (almost) transparently run the kernel at EL2, despite being written for EL1. This patch takes care of the "almost" part, mostly preventing the kernel from dropping from EL2 to EL1, and setting up the HYP configuration. Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> 2016-02-25T10:32:23+00:00 Suzuki K Poulose suzuki.poulose@arm.com 2016-02-23T10:31:42+00:00 urn:sha1:bb9052744f4b7ae11d0061ac9492dd2949981b49 A secondary CPU could fail to come online due to insufficient capabilities and could simply die or loop in the kernel. e.g, a CPU with no support for the selected kernel PAGE_SIZE loops in kernel with MMU turned off. or a hotplugged CPU which doesn't have one of the advertised system capability will die during the activation. There is no way to synchronise the status of the failing CPU back to the master. This patch solves the issue by adding a field to the secondary_data which can be updated by the failing CPU. If the secondary CPU fails even before turning the MMU on, it updates the status in a special variable reserved in the head.txt section to make sure that the update can be cache invalidated safely without possible sharing of cache write back granule. Here are the possible states : -1. CPU_MMU_OFF - Initial value set by the master CPU, this value indicates that the CPU could not turn the MMU on, hence the status could not be reliably updated in the secondary_data. Instead, the CPU has updated the status @ __early_cpu_boot_status. 0. CPU_BOOT_SUCCESS - CPU has booted successfully. 1. CPU_KILL_ME - CPU has invoked cpu_ops->die, indicating the master CPU to synchronise by issuing a cpu_ops->cpu_kill. 2. CPU_STUCK_IN_KERNEL - CPU couldn't invoke die(), instead is looping in the kernel. This information could be used by say, kexec to check if it is really safe to do a kexec reboot. 3. CPU_PANIC_KERNEL - CPU detected some serious issues which requires kernel to crash immediately. The secondary CPU cannot call panic() until it has initialised the GIC. This flag can be used to instruct the master to do so. Cc: Mark Rutland <mark.rutland@arm.com> Acked-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com> [catalin.marinas@arm.com: conflict resolution] [catalin.marinas@arm.com: converted "status" from int to long] [catalin.marinas@arm.com: updated update_early_cpu_boot_status to use str_l] Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> 2016-02-24T14:57:27+00:00 Ard Biesheuvel ard.biesheuvel@linaro.org 2016-01-26T13:12:01+00:00 urn:sha1:f80fb3a3d50843a401dac4b566b3b131da8077a2 This adds support for KASLR is implemented, based on entropy provided by the bootloader in the /chosen/kaslr-seed DT property. Depending on the size of the address space (VA_BITS) and the page size, the entropy in the virtual displacement is up to 13 bits (16k/2 levels) and up to 25 bits (all 4 levels), with the sidenote that displacements that result in the kernel image straddling a 1GB/32MB/512MB alignment boundary (for 4KB/16KB/64KB granule kernels, respectively) are not allowed, and will be rounded up to an acceptable value. If CONFIG_RANDOMIZE_MODULE_REGION_FULL is enabled, the module region is randomized independently from the core kernel. This makes it less likely that the location of core kernel data structures can be determined by an adversary, but causes all function calls from modules into the core kernel to be resolved via entries in the module PLTs. If CONFIG_RANDOMIZE_MODULE_REGION_FULL is not enabled, the module region is randomized by choosing a page aligned 128 MB region inside the interval [_etext - 128 MB, _stext + 128 MB). This gives between 10 and 14 bits of entropy (depending on page size), independently of the kernel randomization, but still guarantees that modules are within the range of relative branch and jump instructions (with the caveat that, since the module region is shared with other uses of the vmalloc area, modules may need to be loaded further away if the module region is exhausted) Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> 2016-02-24T14:57:27+00:00 Ard Biesheuvel ard.biesheuvel@linaro.org 2016-01-26T08:13:44+00:00 urn:sha1:1e48ef7fcc374051730381a2a05da77eb4eafdb0 This implements CONFIG_RELOCATABLE, which links the final vmlinux image with a dynamic relocation section, allowing the early boot code to perform a relocation to a different virtual address at runtime. This is a prerequisite for KASLR (CONFIG_RANDOMIZE_BASE). Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>