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2018-04-24arm64: mm: drop addr parameter from sync icache and dcacheShaokun Zhang1-1/+1
The addr parameter isn't used for anything. Let's simplify and get rid of it, like arm. Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will.deacon@arm.com> Signed-off-by: Shaokun Zhang <zhangshaokun@hisilicon.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-04-17arm64: kasan: avoid pfn_to_nid() before page array is initializedMark Rutland1-2/+2
In arm64's kasan_init(), we use pfn_to_nid() to find the NUMA node a span of memory is in, hoping to allocate shadow from the same NUMA node. However, at this point, the page array has not been initialized, and thus this is bogus. Since commit: f165b378bbdf6c8a ("mm: uninitialized struct page poisoning sanity") ... accessing fields of the page array results in a boot time Oops(), highlighting this problem: [ 0.000000] Unable to handle kernel paging request at virtual address dfff200000000000 [ 0.000000] Mem abort info: [ 0.000000] ESR = 0x96000004 [ 0.000000] Exception class = DABT (current EL), IL = 32 bits [ 0.000000] SET = 0, FnV = 0 [ 0.000000] EA = 0, S1PTW = 0 [ 0.000000] Data abort info: [ 0.000000] ISV = 0, ISS = 0x00000004 [ 0.000000] CM = 0, WnR = 0 [ 0.000000] [dfff200000000000] address between user and kernel address ranges [ 0.000000] Internal error: Oops: 96000004 [#1] PREEMPT SMP [ 0.000000] Modules linked in: [ 0.000000] CPU: 0 PID: 0 Comm: swapper Not tainted 4.16.0-07317-gf165b378bbdf #42 [ 0.000000] Hardware name: ARM Juno development board (r1) (DT) [ 0.000000] pstate: 80000085 (Nzcv daIf -PAN -UAO) [ 0.000000] pc : __asan_load8+0x8c/0xa8 [ 0.000000] lr : __dump_page+0x3c/0x3b8 [ 0.000000] sp : ffff2000099b7ca0 [ 0.000000] x29: ffff2000099b7ca0 x28: ffff20000a1762c0 [ 0.000000] x27: ffff7e0000000000 x26: ffff2000099dd000 [ 0.000000] x25: ffff200009a3f960 x24: ffff200008f9c38c [ 0.000000] x23: ffff20000a9d3000 x22: ffff200009735430 [ 0.000000] x21: fffffffffffffffe x20: ffff7e0001e50420 [ 0.000000] x19: ffff7e0001e50400 x18: 0000000000001840 [ 0.000000] x17: ffffffffffff8270 x16: 0000000000001840 [ 0.000000] x15: 0000000000001920 x14: 0000000000000004 [ 0.000000] x13: 0000000000000000 x12: 0000000000000800 [ 0.000000] x11: 1ffff0012d0f89ff x10: ffff10012d0f89ff [ 0.000000] x9 : 0000000000000000 x8 : ffff8009687c5000 [ 0.000000] x7 : 0000000000000000 x6 : ffff10000f282000 [ 0.000000] x5 : 0000000000000040 x4 : fffffffffffffffe [ 0.000000] x3 : 0000000000000000 x2 : dfff200000000000 [ 0.000000] x1 : 0000000000000005 x0 : 0000000000000000 [ 0.000000] Process swapper (pid: 0, stack limit = 0x (ptrval)) [ 0.000000] Call trace: [ 0.000000] __asan_load8+0x8c/0xa8 [ 0.000000] __dump_page+0x3c/0x3b8 [ 0.000000] dump_page+0xc/0x18 [ 0.000000] kasan_init+0x2e8/0x5a8 [ 0.000000] setup_arch+0x294/0x71c [ 0.000000] start_kernel+0xdc/0x500 [ 0.000000] Code: aa0403e0 9400063c 17ffffee d343fc00 (38e26800) [ 0.000000] ---[ end trace 67064f0e9c0cc338 ]--- [ 0.000000] Kernel panic - not syncing: Attempted to kill the idle task! [ 0.000000] ---[ end Kernel panic - not syncing: Attempted to kill the idle task! ]--- Let's fix this by using early_pfn_to_nid(), as other architectures do in their kasan init code. Note that early_pfn_to_nid acquires the nid from the memblock array, which we iterate over in kasan_init(), so this should be fine. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Fixes: 39d114ddc6822302 ("arm64: add KASAN support") Cc: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-04-11exec: pass stack rlimit into mm layout functionsKees Cook1-7/+7
Patch series "exec: Pin stack limit during exec". Attempts to solve problems with the stack limit changing during exec continue to be frustrated[1][2]. In addition to the specific issues around the Stack Clash family of flaws, Andy Lutomirski pointed out[3] other places during exec where the stack limit is used and is assumed to be unchanging. Given the many places it gets used and the fact that it can be manipulated/raced via setrlimit() and prlimit(), I think the only way to handle this is to move away from the "current" view of the stack limit and instead attach it to the bprm, and plumb this down into the functions that need to know the stack limits. This series implements the approach. [1] 04e35f4495dd ("exec: avoid RLIMIT_STACK races with prlimit()") [2] 779f4e1c6c7c ("Revert "exec: avoid RLIMIT_STACK races with prlimit()"") [3] to security@kernel.org, "Subject: existing rlimit races?" This patch (of 3): Since it is possible that the stack rlimit can change externally during exec (either via another thread calling setrlimit() or another process calling prlimit()), provide a way to pass the rlimit down into the per-architecture mm layout functions so that the rlimit can stay in the bprm structure instead of sitting in the signal structure until exec is finalized. Link: http://lkml.kernel.org/r/1518638796-20819-2-git-send-email-keescook@chromium.org Signed-off-by: Kees Cook <keescook@chromium.org> Cc: Michal Hocko <mhocko@kernel.org> Cc: Ben Hutchings <ben@decadent.org.uk> Cc: Willy Tarreau <w@1wt.eu> Cc: Hugh Dickins <hughd@google.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: "Jason A. Donenfeld" <Jason@zx2c4.com> Cc: Rik van Riel <riel@redhat.com> Cc: Laura Abbott <labbott@redhat.com> Cc: Greg KH <greg@kroah.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Ben Hutchings <ben.hutchings@codethink.co.uk> Cc: Brad Spengler <spender@grsecurity.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-04Merge tag 'arm64-upstream' of ↵Linus Torvalds3-142/+137
git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux Pull arm64 updates from Will Deacon: "Nothing particularly stands out here, probably because people were tied up with spectre/meltdown stuff last time around. Still, the main pieces are: - Rework of our CPU features framework so that we can whitelist CPUs that don't require kpti even in a heterogeneous system - Support for the IDC/DIC architecture extensions, which allow us to elide instruction and data cache maintenance when writing out instructions - Removal of the large memory model which resulted in suboptimal codegen by the compiler and increased the use of literal pools, which could potentially be used as ROP gadgets since they are mapped as executable - Rework of forced signal delivery so that the siginfo_t is well-formed and handling of show_unhandled_signals is consolidated and made consistent between different fault types - More siginfo cleanup based on the initial patches from Eric Biederman - Workaround for Cortex-A55 erratum #1024718 - Some small ACPI IORT updates and cleanups from Lorenzo Pieralisi - Misc cleanups and non-critical fixes" * tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (70 commits) arm64: uaccess: Fix omissions from usercopy whitelist arm64: fpsimd: Split cpu field out from struct fpsimd_state arm64: tlbflush: avoid writing RES0 bits arm64: cmpxchg: Include linux/compiler.h in asm/cmpxchg.h arm64: move percpu cmpxchg implementation from cmpxchg.h to percpu.h arm64: cmpxchg: Include build_bug.h instead of bug.h for BUILD_BUG arm64: lse: Include compiler_types.h and export.h for out-of-line LL/SC arm64: fpsimd: include <linux/init.h> in fpsimd.h drivers/perf: arm_pmu_platform: do not warn about affinity on uniprocessor perf: arm_spe: include linux/vmalloc.h for vmap() Revert "arm64: Revert L1_CACHE_SHIFT back to 6 (64-byte cache line size)" arm64: cpufeature: Avoid warnings due to unused symbols arm64: Add work around for Arm Cortex-A55 Erratum 1024718 arm64: Delay enabling hardware DBM feature arm64: Add MIDR encoding for Arm Cortex-A55 and Cortex-A35 arm64: capabilities: Handle shared entries arm64: capabilities: Add support for checks based on a list of MIDRs arm64: Add helpers for checking CPU MIDR against a range arm64: capabilities: Clean up midr range helpers arm64: capabilities: Change scope of VHE to Boot CPU feature ...
2018-03-27Revert "arm64: Revert L1_CACHE_SHIFT back to 6 (64-byte cache line size)"Will Deacon2-19/+1
This reverts commit 1f85b42a691cd8329ba82dbcaeec80ac1231b32a. The internal dma-direct.h API has changed in -next, which collides with us trying to use it to manage non-coherent DMA devices on systems with unreasonably large cache writeback granules. This isn't at all trivial to resolve, so revert our changes for now and we can revisit this after the merge window. Effectively, this just restores our behaviour back to that of 4.16. Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-03-26arm64: Delay enabling hardware DBM featureSuzuki K Poulose1-7/+6
We enable hardware DBM bit in a capable CPU, very early in the boot via __cpu_setup. This doesn't give us a flexibility of optionally disable the feature, as the clearing the bit is a bit costly as the TLB can cache the settings. Instead, we delay enabling the feature until the CPU is brought up into the kernel. We use the feature capability mechanism to handle it. The hardware DBM is a non-conflicting feature. i.e, the kernel can safely run with a mix of CPUs with some using the feature and the others don't. So, it is safe for a late CPU to have this capability and enable it, even if the active CPUs don't. To get this handled properly by the infrastructure, we unconditionally set the capability and only enable it on CPUs which really have the feature. Also, we print the feature detection from the "matches" call back to make sure we don't mislead the user when none of the CPUs could use the feature. Cc: Catalin Marinas <catalin.marinas@arm.com> Reviewed-by: Dave Martin <dave.martin@arm.com> Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-03-26arm64: capabilities: Update prototype for enable call backDave Martin1-2/+1
We issue the enable() call back for all CPU hwcaps capabilities available on the system, on all the CPUs. So far we have ignored the argument passed to the call back, which had a prototype to accept a "void *" for use with on_each_cpu() and later with stop_machine(). However, with commit 0a0d111d40fd1 ("arm64: cpufeature: Pass capability structure to ->enable callback"), there are some users of the argument who wants the matching capability struct pointer where there are multiple matching criteria for a single capability. Clean up the declaration of the call back to make it clear. 1) Renamed to cpu_enable(), to imply taking necessary actions on the called CPU for the entry. 2) Pass const pointer to the capability, to allow the call back to check the entry. (e.,g to check if any action is needed on the CPU) 3) We don't care about the result of the call back, turning this to a void. Cc: Will Deacon <will.deacon@arm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Andre Przywara <andre.przywara@arm.com> Cc: James Morse <james.morse@arm.com> Acked-by: Robin Murphy <robin.murphy@arm.com> Reviewed-by: Julien Thierry <julien.thierry@arm.com> Signed-off-by: Dave Martin <dave.martin@arm.com> [suzuki: convert more users, rename call back and drop results] Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-03-22mm/vmalloc: add interfaces to free unmapped page tableToshi Kani1-0/+10
On architectures with CONFIG_HAVE_ARCH_HUGE_VMAP set, ioremap() may create pud/pmd mappings. A kernel panic was observed on arm64 systems with Cortex-A75 in the following steps as described by Hanjun Guo. 1. ioremap a 4K size, valid page table will build, 2. iounmap it, pte0 will set to 0; 3. ioremap the same address with 2M size, pgd/pmd is unchanged, then set the a new value for pmd; 4. pte0 is leaked; 5. CPU may meet exception because the old pmd is still in TLB, which will lead to kernel panic. This panic is not reproducible on x86. INVLPG, called from iounmap, purges all levels of entries associated with purged address on x86. x86 still has memory leak. The patch changes the ioremap path to free unmapped page table(s) since doing so in the unmap path has the following issues: - The iounmap() path is shared with vunmap(). Since vmap() only supports pte mappings, making vunmap() to free a pte page is an overhead for regular vmap users as they do not need a pte page freed up. - Checking if all entries in a pte page are cleared in the unmap path is racy, and serializing this check is expensive. - The unmap path calls free_vmap_area_noflush() to do lazy TLB purges. Clearing a pud/pmd entry before the lazy TLB purges needs extra TLB purge. Add two interfaces, pud_free_pmd_page() and pmd_free_pte_page(), which clear a given pud/pmd entry and free up a page for the lower level entries. This patch implements their stub functions on x86 and arm64, which work as workaround. [akpm@linux-foundation.org: fix typo in pmd_free_pte_page() stub] Link: http://lkml.kernel.org/r/20180314180155.19492-2-toshi.kani@hpe.com Fixes: e61ce6ade404e ("mm: change ioremap to set up huge I/O mappings") Reported-by: Lei Li <lious.lilei@hisilicon.com> Signed-off-by: Toshi Kani <toshi.kani@hpe.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Wang Xuefeng <wxf.wang@hisilicon.com> Cc: Will Deacon <will.deacon@arm.com> Cc: Hanjun Guo <guohanjun@huawei.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Borislav Petkov <bp@suse.de> Cc: Matthew Wilcox <willy@infradead.org> Cc: Chintan Pandya <cpandya@codeaurora.org> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-03-09arm64: signal: Ensure si_code is valid for all fault signalsDave Martin1-58/+58
Currently, as reported by Eric, an invalid si_code value 0 is passed in many signals delivered to userspace in response to faults and other kernel errors. Typically 0 is passed when the fault is insufficiently diagnosable or when there does not appear to be any sensible alternative value to choose. This appears to violate POSIX, and is intuitively wrong for at least two reasons arising from the fact that 0 == SI_USER: 1) si_code is a union selector, and SI_USER (and si_code <= 0 in general) implies the existence of a different set of fields (siginfo._kill) from that which exists for a fault signal (siginfo._sigfault). However, the code raising the signal typically writes only the _sigfault fields, and the _kill fields make no sense in this case. Thus when userspace sees si_code == 0 (SI_USER) it may legitimately inspect fields in the inactive union member _kill and obtain garbage as a result. There appears to be software in the wild relying on this, albeit generally only for printing diagnostic messages. 2) Software that wants to be robust against spurious signals may discard signals where si_code == SI_USER (or <= 0), or may filter such signals based on the si_uid and si_pid fields of siginfo._sigkill. In the case of fault signals, this means that important (and usually fatal) error conditions may be silently ignored. In practice, many of the faults for which arm64 passes si_code == 0 are undiagnosable conditions such as exceptions with syndrome values in ESR_ELx to which the architecture does not yet assign any meaning, or conditions indicative of a bug or error in the kernel or system and thus that are unrecoverable and should never occur in normal operation. The approach taken in this patch is to translate all such undiagnosable or "impossible" synchronous fault conditions to SIGKILL, since these are at least probably localisable to a single process. Some of these conditions should really result in a kernel panic, but due to the lack of diagnostic information it is difficult to be certain: this patch does not add any calls to panic(), but this could change later if justified. Although si_code will not reach userspace in the case of SIGKILL, it is still desirable to pass a nonzero value so that the common siginfo handling code can detect incorrect use of si_code == 0 without false positives. In this case the si_code dependent siginfo fields will not be correctly initialised, but since they are not passed to userspace I deem this not to matter. A few faults can reasonably occur in realistic userspace scenarios, and _should_ raise a regular, handleable (but perhaps not ignorable/blockable) signal: for these, this patch attempts to choose a suitable standard si_code value for the raised signal in each case instead of 0. arm64 was the only arch to define a BUS_FIXME code, so after this patch nobody defines it. This patch therefore also removes the relevant code from siginfo_layout(). Cc: James Morse <james.morse@arm.com> Reported-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: Dave Martin <Dave.Martin@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-03-09arm64: Add support for new control bits CTR_EL0.DIC and CTR_EL0.IDCShanker Donthineni1-1/+20
The DCache clean & ICache invalidation requirements for instructions to be data coherence are discoverable through new fields in CTR_EL0. The following two control bits DIC and IDC were defined for this purpose. No need to perform point of unification cache maintenance operations from software on systems where CPU caches are transparent. This patch optimize the three functions __flush_cache_user_range(), clean_dcache_area_pou() and invalidate_icache_range() if the hardware reports CTR_EL0.IDC and/or CTR_EL0.IDC. Basically it skips the two instructions 'DC CVAU' and 'IC IVAU', and the associated loop logic in order to avoid the unnecessary overhead. CTR_EL0.DIC: Instruction cache invalidation requirements for instruction to data coherence. The meaning of this bit[29]. 0: Instruction cache invalidation to the point of unification is required for instruction to data coherence. 1: Instruction cache cleaning to the point of unification is not required for instruction to data coherence. CTR_EL0.IDC: Data cache clean requirements for instruction to data coherence. The meaning of this bit[28]. 0: Data cache clean to the point of unification is required for instruction to data coherence, unless CLIDR_EL1.LoC == 0b000 or (CLIDR_EL1.LoUIS == 0b000 && CLIDR_EL1.LoUU == 0b000). 1: Data cache clean to the point of unification is not required for instruction to data coherence. Co-authored-by: Philip Elcan <pelcan@codeaurora.org> Reviewed-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Shanker Donthineni <shankerd@codeaurora.org> Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-03-06arm64: kaslr: Set TCR_EL1.NFD1 when CONFIG_RANDOMIZE_BASE=yWill Deacon1-1/+8
TCR_EL1.NFD1 was allocated by SVE and ensures that fault-surpressing SVE memory accesses (e.g. speculative accesses from a first-fault gather load) which translate via TTBR1_EL1 result in a translation fault if they miss in the TLB when executed from EL0. This mitigates some timing attacks against KASLR, where the kernel address space could otherwise be probed efficiently using the FFR in conjunction with suppressed faults on SVE loads. Cc: Dave Martin <Dave.Martin@arm.com> Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-03-06arm64: Revert L1_CACHE_SHIFT back to 6 (64-byte cache line size)Catalin Marinas2-1/+19
Commit 97303480753e ("arm64: Increase the max granular size") increased the cache line size to 128 to match Cavium ThunderX, apparently for some performance benefit which could not be confirmed. This change, however, has an impact on the network packets allocation in certain circumstances, requiring slightly over a 4K page with a significant performance degradation. This patch reverts L1_CACHE_SHIFT back to 6 (64-byte cache line) while keeping ARCH_DMA_MINALIGN at 128. The cache_line_size() function was changed to default to ARCH_DMA_MINALIGN in the absence of a meaningful CTR_EL0.CWG bit field. In addition, if a system with ARCH_DMA_MINALIGN < CTR_EL0.CWG is detected, the kernel will force swiotlb bounce buffering for all non-coherent devices since DMA cache maintenance on sub-CWG ranges is not safe, leading to data corruption. Cc: Tirumalesh Chalamarla <tchalamarla@cavium.com> Cc: Timur Tabi <timur@codeaurora.org> Cc: Florian Fainelli <f.fainelli@gmail.com> Acked-by: Robin Murphy <robin.murphy@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-03-06arm64: mm: Rework unhandled user pagefaults to call arm64_force_sig_infoWill Deacon1-51/+36
Reporting unhandled user pagefaults via arm64_force_sig_info means that __do_user_fault can be drastically simplified, since it no longer has to worry about printing the fault information and can consequently just take the siginfo as a parameter. Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-03-06arm64: Pass user fault info to arm64_notify_die instead of printing itWill Deacon1-22/+8
There's no need for callers of arm64_notify_die to print information about user faults. Instead, they can pass a string to arm64_notify_die which will be printed subject to show_unhandled_signals. Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-02-26arm64: mm: fix thinko in non-global page table attribute checkArd Biesheuvel1-4/+4
The routine pgattr_change_is_safe() was extended in commit 4e6020565596 ("arm64: mm: Permit transitioning from Global to Non-Global without BBM") to permit changing the nG attribute from not set to set, but did so in a way that inadvertently disallows such changes if other permitted attribute changes take place at the same time. So update the code to take this into account. Fixes: 4e6020565596 ("arm64: mm: Permit transitioning from Global to ...") Cc: <stable@vger.kernel.org> # 4.14.x- Acked-by: Mark Rutland <mark.rutland@arm.com> Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Acked-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-02-22arm64: Enforce BBM for huge IO/VMAP mappingsWill Deacon1-0/+10
ioremap_page_range doesn't honour break-before-make and attempts to put down huge mappings (using p*d_set_huge) over the top of pre-existing table entries. This leads to us leaking page table memory and also gives rise to TLB conflicts and spurious aborts, which have been seen in practice on Cortex-A75. Until this has been resolved, refuse to put block mappings when the existing entry is found to be present. Fixes: 324420bf91f60 ("arm64: add support for ioremap() block mappings") Reported-by: Hanjun Guo <hanjun.guo@linaro.org> Reported-by: Lei Li <lious.lilei@hisilicon.com> Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-02-16arm64: mm: Use READ_ONCE/WRITE_ONCE when accessing page tablesWill Deacon6-278/+298
In many cases, page tables can be accessed concurrently by either another CPU (due to things like fast gup) or by the hardware page table walker itself, which may set access/dirty bits. In such cases, it is important to use READ_ONCE/WRITE_ONCE when accessing page table entries so that entries cannot be torn, merged or subject to apparent loss of coherence due to compiler transformations. Whilst there are some scenarios where this cannot happen (e.g. pinned kernel mappings for the linear region), the overhead of using READ_ONCE /WRITE_ONCE everywhere is minimal and makes the code an awful lot easier to reason about. This patch consistently uses these macros in the arch code, as well as explicitly namespacing pointers to page table entries from the entries themselves by using adopting a 'p' suffix for the former (as is sometimes used elsewhere in the kernel source). Tested-by: Yury Norov <ynorov@caviumnetworks.com> Tested-by: Richard Ruigrok <rruigrok@codeaurora.org> Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-02-14arm64: proc: Set PTE_NG for table entries to avoid traversing them twiceWill Deacon1-5/+9
When KASAN is enabled, the swapper page table contains many identical mappings of the zero page, which can lead to a stall during boot whilst the G -> nG code continually walks the same page table entries looking for global mappings. This patch sets the nG bit (bit 11, which is IGNORED) in table entries after processing the subtree so we can easily skip them if we see them a second time. Tested-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-02-10Merge tag 'kvm-4.16-1' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds1-10/+22
Pull KVM updates from Radim Krčmář: "ARM: - icache invalidation optimizations, improving VM startup time - support for forwarded level-triggered interrupts, improving performance for timers and passthrough platform devices - a small fix for power-management notifiers, and some cosmetic changes PPC: - add MMIO emulation for vector loads and stores - allow HPT guests to run on a radix host on POWER9 v2.2 CPUs without requiring the complex thread synchronization of older CPU versions - improve the handling of escalation interrupts with the XIVE interrupt controller - support decrement register migration - various cleanups and bugfixes. s390: - Cornelia Huck passed maintainership to Janosch Frank - exitless interrupts for emulated devices - cleanup of cpuflag handling - kvm_stat counter improvements - VSIE improvements - mm cleanup x86: - hypervisor part of SEV - UMIP, RDPID, and MSR_SMI_COUNT emulation - paravirtualized TLB shootdown using the new KVM_VCPU_PREEMPTED bit - allow guests to see TOPOEXT, GFNI, VAES, VPCLMULQDQ, and more AVX512 features - show vcpu id in its anonymous inode name - many fixes and cleanups - per-VCPU MSR bitmaps (already merged through x86/pti branch) - stable KVM clock when nesting on Hyper-V (merged through x86/hyperv)" * tag 'kvm-4.16-1' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (197 commits) KVM: PPC: Book3S: Add MMIO emulation for VMX instructions KVM: PPC: Book3S HV: Branch inside feature section KVM: PPC: Book3S HV: Make HPT resizing work on POWER9 KVM: PPC: Book3S HV: Fix handling of secondary HPTEG in HPT resizing code KVM: PPC: Book3S PR: Fix broken select due to misspelling KVM: x86: don't forget vcpu_put() in kvm_arch_vcpu_ioctl_set_sregs() KVM: PPC: Book3S PR: Fix svcpu copying with preemption enabled KVM: PPC: Book3S HV: Drop locks before reading guest memory kvm: x86: remove efer_reload entry in kvm_vcpu_stat KVM: x86: AMD Processor Topology Information x86/kvm/vmx: do not use vm-exit instruction length for fast MMIO when running nested kvm: embed vcpu id to dentry of vcpu anon inode kvm: Map PFN-type memory regions as writable (if possible) x86/kvm: Make it compile on 32bit and with HYPYERVISOR_GUEST=n KVM: arm/arm64: Fixup userspace irqchip static key optimization KVM: arm/arm64: Fix userspace_irqchip_in_use counting KVM: arm/arm64: Fix incorrect timer_is_pending logic MAINTAINERS: update KVM/s390 maintainers MAINTAINERS: add Halil as additional vfio-ccw maintainer MAINTAINERS: add David as a reviewer for KVM/s390 ...
2018-02-08Merge tag 'arm64-upstream' of ↵Linus Torvalds3-14/+221
git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux Pull more arm64 updates from Catalin Marinas: "As I mentioned in the last pull request, there's a second batch of security updates for arm64 with mitigations for Spectre/v1 and an improved one for Spectre/v2 (via a newly defined firmware interface API). Spectre v1 mitigation: - back-end version of array_index_mask_nospec() - masking of the syscall number to restrict speculation through the syscall table - masking of __user pointers prior to deference in uaccess routines Spectre v2 mitigation update: - using the new firmware SMC calling convention specification update - removing the current PSCI GET_VERSION firmware call mitigation as vendors are deploying new SMCCC-capable firmware - additional branch predictor hardening for synchronous exceptions and interrupts while in user mode Meltdown v3 mitigation update: - Cavium Thunder X is unaffected but a hardware erratum gets in the way. The kernel now starts with the page tables mapped as global and switches to non-global if kpti needs to be enabled. Other: - Theoretical trylock bug fixed" * tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (38 commits) arm64: Kill PSCI_GET_VERSION as a variant-2 workaround arm64: Add ARM_SMCCC_ARCH_WORKAROUND_1 BP hardening support arm/arm64: smccc: Implement SMCCC v1.1 inline primitive arm/arm64: smccc: Make function identifiers an unsigned quantity firmware/psci: Expose SMCCC version through psci_ops firmware/psci: Expose PSCI conduit arm64: KVM: Add SMCCC_ARCH_WORKAROUND_1 fast handling arm64: KVM: Report SMCCC_ARCH_WORKAROUND_1 BP hardening support arm/arm64: KVM: Turn kvm_psci_version into a static inline arm/arm64: KVM: Advertise SMCCC v1.1 arm/arm64: KVM: Implement PSCI 1.0 support arm/arm64: KVM: Add smccc accessors to PSCI code arm/arm64: KVM: Add PSCI_VERSION helper arm/arm64: KVM: Consolidate the PSCI include files arm64: KVM: Increment PC after handling an SMC trap arm: KVM: Fix SMCCC handling of unimplemented SMC/HVC calls arm64: KVM: Fix SMCCC handling of unimplemented SMC/HVC calls arm64: entry: Apply BP hardening for suspicious interrupts from EL0 arm64: entry: Apply BP hardening for high-priority synchronous exceptions arm64: futex: Mask __user pointers prior to dereference ...
2018-02-06Merge branch 'akpm' (patches from Andrew)Linus Torvalds1-1/+2
Merge misc updates from Andrew Morton: - kasan updates - procfs - lib/bitmap updates - other lib/ updates - checkpatch tweaks - rapidio - ubsan - pipe fixes and cleanups - lots of other misc bits * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (114 commits) Documentation/sysctl/user.txt: fix typo MAINTAINERS: update ARM/QUALCOMM SUPPORT patterns MAINTAINERS: update various PALM patterns MAINTAINERS: update "ARM/OXNAS platform support" patterns MAINTAINERS: update Cortina/Gemini patterns MAINTAINERS: remove ARM/CLKDEV SUPPORT file pattern MAINTAINERS: remove ANDROID ION pattern mm: docs: add blank lines to silence sphinx "Unexpected indentation" errors mm: docs: fix parameter names mismatch mm: docs: fixup punctuation pipe: read buffer limits atomically pipe: simplify round_pipe_size() pipe: reject F_SETPIPE_SZ with size over UINT_MAX pipe: fix off-by-one error when checking buffer limits pipe: actually allow root to exceed the pipe buffer limits pipe, sysctl: remove pipe_proc_fn() pipe, sysctl: drop 'min' parameter from pipe-max-size converter kasan: rework Kconfig settings crash_dump: is_kdump_kernel can be boolean kernel/mutex: mutex_is_locked can be boolean ...
2018-02-06kasan: clean up KASAN_SHADOW_SCALE_SHIFT usageAndrey Konovalov1-1/+2
Right now the fact that KASAN uses a single shadow byte for 8 bytes of memory is scattered all over the code. This change defines KASAN_SHADOW_SCALE_SHIFT early in asm include files and makes use of this constant where necessary. [akpm@linux-foundation.org: coding-style fixes] Link: http://lkml.kernel.org/r/34937ca3b90736eaad91b568edf5684091f662e3.1515775666.git.andreyknvl@google.com Signed-off-by: Andrey Konovalov <andreyknvl@google.com> Acked-by: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Dmitry Vyukov <dvyukov@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-02-06arm64: entry: Apply BP hardening for suspicious interrupts from EL0Will Deacon1-0/+6
It is possible to take an IRQ from EL0 following a branch to a kernel address in such a way that the IRQ is prioritised over the instruction abort. Whilst an attacker would need to get the stars to align here, it might be sufficient with enough calibration so perform BP hardening in the rare case that we see a kernel address in the ELR when handling an IRQ from EL0. Reported-by: Dan Hettena <dhettena@nvidia.com> Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-02-06arm64: entry: Apply BP hardening for high-priority synchronous exceptionsWill Deacon1-0/+9
Software-step and PC alignment fault exceptions have higher priority than instruction abort exceptions, so apply the BP hardening hooks there too if the user PC appears to reside in kernel space. Reported-by: Dan Hettena <dhettena@nvidia.com> Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-02-06arm64: Make USER_DS an inclusive limitRobin Murphy1-2/+2
Currently, USER_DS represents an exclusive limit while KERNEL_DS is inclusive. In order to do some clever trickery for speculation-safe masking, we need them both to behave equivalently - there aren't enough bits to make KERNEL_DS exclusive, so we have precisely one option. This also happens to correct a longstanding false negative for a range ending on the very top byte of kernel memory. Mark Rutland points out that we've actually got the semantics of addresses vs. segments muddled up in most of the places we need to amend, so shuffle the {USER,KERNEL}_DS definitions around such that we can correct those properly instead of just pasting "-1"s everywhere. Signed-off-by: Robin Murphy <robin.murphy@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-02-06arm64: idmap: Use "awx" flags for .idmap.text .pushsection directivesWill Deacon1-4/+4
The identity map is mapped as both writeable and executable by the SWAPPER_MM_MMUFLAGS and this is relied upon by the kpti code to manage a synchronisation flag. Update the .pushsection flags to reflect the actual mapping attributes. Reported-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-02-06arm64: assembler: Change order of macro arguments in phys_to_ttbrWill Deacon1-3/+3
Since AArch64 assembly instructions take the destination register as their first operand, do the same thing for the phys_to_ttbr macro. Acked-by: Robin Murphy <robin.murphy@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-02-06arm64: kpti: Add ->enable callback to remap swapper using nG mappingsWill Deacon1-8/+196
Defaulting to global mappings for kernel space is generally good for performance and appears to be necessary for Cavium ThunderX. If we subsequently decide that we need to enable kpti, then we need to rewrite our existing page table entries to be non-global. This is fiddly, and made worse by the possible use of contiguous mappings, which require a strict break-before-make sequence. Since the enable callback runs on each online CPU from stop_machine context, we can have all CPUs enter the idmap, where secondaries can wait for the primary CPU to rewrite swapper with its MMU off. It's all fairly horrible, but at least it only runs once. Tested-by: Marc Zyngier <marc.zyngier@arm.com> Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-02-06arm64: mm: Permit transitioning from Global to Non-Global without BBMWill Deacon1-0/+4
Break-before-make is not needed when transitioning from Global to Non-Global mappings, provided that the contiguous hint is not being used. Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-02-06Merge tag 'libnvdimm-for-4.16' of ↵Linus Torvalds1-3/+6
git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm Pull libnvdimm updates from Ross Zwisler: - Require struct page by default for filesystem DAX to remove a number of surprising failure cases. This includes failures with direct I/O, gdb and fork(2). - Add support for the new Platform Capabilities Structure added to the NFIT in ACPI 6.2a. This new table tells us whether the platform supports flushing of CPU and memory controller caches on unexpected power loss events. - Revamp vmem_altmap and dev_pagemap handling to clean up code and better support future future PCI P2P uses. - Deprecate the ND_IOCTL_SMART_THRESHOLD command whose payload has become out-of-sync with recent versions of the NVDIMM_FAMILY_INTEL spec, and instead rely on the generic ND_CMD_CALL approach used by the two other IOCTL families, NVDIMM_FAMILY_{HPE,MSFT}. - Enhance nfit_test so we can test some of the new things added in version 1.6 of the DSM specification. This includes testing firmware download and simulating the Last Shutdown State (LSS) status. * tag 'libnvdimm-for-4.16' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm: (37 commits) libnvdimm, namespace: remove redundant initialization of 'nd_mapping' acpi, nfit: fix register dimm error handling libnvdimm, namespace: make min namespace size 4K tools/testing/nvdimm: force nfit_test to depend on instrumented modules libnvdimm/nfit_test: adding support for unit testing enable LSS status libnvdimm/nfit_test: add firmware download emulation nfit-test: Add platform cap support from ACPI 6.2a to test libnvdimm: expose platform persistence attribute for nd_region acpi: nfit: add persistent memory control flag for nd_region acpi: nfit: Add support for detect platform CPU cache flush on power loss device-dax: Fix trailing semicolon libnvdimm, btt: fix uninitialized err_lock dax: require 'struct page' by default for filesystem dax ext2: auto disable dax instead of failing mount ext4: auto disable dax instead of failing mount mm, dax: introduce pfn_t_special() mm: Fix devm_memremap_pages() collision handling mm: Fix memory size alignment in devm_memremap_pages_release() memremap: merge find_dev_pagemap into get_dev_pagemap memremap: change devm_memremap_pages interface to use struct dev_pagemap ...
2018-02-01Merge branch 'x86/hyperv' of ↵Radim Krčmář3-5/+5
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Topic branch for stable KVM clockource under Hyper-V. Thanks to Christoffer Dall for resolving the ARM conflict.
2018-01-31Merge tag 'dma-mapping-4.16' of git://git.infradead.org/users/hch/dma-mappingLinus Torvalds2-55/+15
Pull dma mapping updates from Christoph Hellwig: "Except for a runtime warning fix from Christian this is all about consolidation of the generic no-IOMMU code, a well as the glue code for swiotlb. All the code is based on the x86 implementation with hooks to allow all architectures that aren't cache coherent to use it. The x86 conversion itself has been deferred because the x86 maintainers were a little busy in the last months" * tag 'dma-mapping-4.16' of git://git.infradead.org/users/hch/dma-mapping: (57 commits) MAINTAINERS: add the iommu list for swiotlb and xen-swiotlb arm64: use swiotlb_alloc and swiotlb_free arm64: replace ZONE_DMA with ZONE_DMA32 mips: use swiotlb_{alloc,free} mips/netlogic: remove swiotlb support tile: use generic swiotlb_ops tile: replace ZONE_DMA with ZONE_DMA32 unicore32: use generic swiotlb_ops ia64: remove an ifdef around the content of pci-dma.c ia64: clean up swiotlb support ia64: use generic swiotlb_ops ia64: replace ZONE_DMA with ZONE_DMA32 swiotlb: remove various exports swiotlb: refactor coherent buffer allocation swiotlb: refactor coherent buffer freeing swiotlb: wire up ->dma_supported in swiotlb_dma_ops swiotlb: add common swiotlb_map_ops swiotlb: rename swiotlb_free to swiotlb_exit x86: rename swiotlb_dma_ops powerpc: rename swiotlb_dma_ops ...
2018-01-30Merge branch 'siginfo-linus' of ↵Linus Torvalds1-57/+57
git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace Pull siginfo cleanups from Eric Biederman: "Long ago when 2.4 was just a testing release copy_siginfo_to_user was made to copy individual fields to userspace, possibly for efficiency and to ensure initialized values were not copied to userspace. Unfortunately the design was complex, it's assumptions unstated, and humans are fallible and so while it worked much of the time that design failed to ensure unitialized memory is not copied to userspace. This set of changes is part of a new design to clean up siginfo and simplify things, and hopefully make the siginfo handling robust enough that a simple inspection of the code can be made to ensure we don't copy any unitializied fields to userspace. The design is to unify struct siginfo and struct compat_siginfo into a single definition that is shared between all architectures so that anyone adding to the set of information shared with struct siginfo can see the whole picture. Hopefully ensuring all future si_code assignments are arch independent. The design is to unify copy_siginfo_to_user32 and copy_siginfo_from_user32 so that those function are complete and cope with all of the different cases documented in signinfo_layout. I don't think there was a single implementation of either of those functions that was complete and correct before my changes unified them. The design is to introduce a series of helpers including force_siginfo_fault that take the values that are needed in struct siginfo and build the siginfo structure for their callers. Ensuring struct siginfo is built correctly. The remaining work for 4.17 (unless someone thinks it is post -rc1 material) is to push usage of those helpers down into the architectures so that architecture specific code will not need to deal with the fiddly work of intializing struct siginfo, and then when struct siginfo is guaranteed to be fully initialized change copy siginfo_to_user into a simple wrapper around copy_to_user. Further there is work in progress on the issues that have been documented requires arch specific knowledge to sort out. The changes below fix or at least document all of the issues that have been found with siginfo generation. Then proceed to unify struct siginfo the 32 bit helpers that copy siginfo to and from userspace, and generally clean up anything that is not arch specific with regards to siginfo generation. It is a lot but with the unification you can of siginfo you can already see the code reduction in the kernel" * 'siginfo-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: (45 commits) signal/memory-failure: Use force_sig_mceerr and send_sig_mceerr mm/memory_failure: Remove unused trapno from memory_failure signal/ptrace: Add force_sig_ptrace_errno_trap and use it where needed signal/powerpc: Remove unnecessary signal_code parameter of do_send_trap signal: Helpers for faults with specialized siginfo layouts signal: Add send_sig_fault and force_sig_fault signal: Replace memset(info,...) with clear_siginfo for clarity signal: Don't use structure initializers for struct siginfo signal/arm64: Better isolate the COMPAT_TASK portion of ptrace_hbptriggered ptrace: Use copy_siginfo in setsiginfo and getsiginfo signal: Unify and correct copy_siginfo_to_user32 signal: Remove the code to clear siginfo before calling copy_siginfo_from_user32 signal: Unify and correct copy_siginfo_from_user32 signal/blackfin: Remove pointless UID16_SIGINFO_COMPAT_NEEDED signal/blackfin: Move the blackfin specific si_codes to asm-generic/siginfo.h signal/tile: Move the tile specific si_codes to asm-generic/siginfo.h signal/frv: Move the frv specific si_codes to asm-generic/siginfo.h signal/ia64: Move the ia64 specific si_codes to asm-generic/siginfo.h signal/powerpc: Remove redefinition of NSIGTRAP on powerpc signal: Move addr_lsb into the _sigfault union for clarity ...
2018-01-30Merge tag 'arm64-upstream' of ↵Linus Torvalds7-113/+142
git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux Pull arm64 updates from Catalin Marinas: "The main theme of this pull request is security covering variants 2 and 3 for arm64. I expect to send additional patches next week covering an improved firmware interface (requires firmware changes) for variant 2 and way for KPTI to be disabled on unaffected CPUs (Cavium's ThunderX doesn't work properly with KPTI enabled because of a hardware erratum). Summary: - Security mitigations: - variant 2: invalidate the branch predictor with a call to secure firmware - variant 3: implement KPTI for arm64 - 52-bit physical address support for arm64 (ARMv8.2) - arm64 support for RAS (firmware first only) and SDEI (software delegated exception interface; allows firmware to inject a RAS error into the OS) - perf support for the ARM DynamIQ Shared Unit PMU - CPUID and HWCAP bits updated for new floating point multiplication instructions in ARMv8.4 - remove some virtual memory layout printks during boot - fix initial page table creation to cope with larger than 32M kernel images when 16K pages are enabled" * tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (104 commits) arm64: Fix TTBR + PAN + 52-bit PA logic in cpu_do_switch_mm arm64: Turn on KPTI only on CPUs that need it arm64: Branch predictor hardening for Cavium ThunderX2 arm64: Run enable method for errata work arounds on late CPUs arm64: Move BP hardening to check_and_switch_context arm64: mm: ignore memory above supported physical address size arm64: kpti: Fix the interaction between ASID switching and software PAN KVM: arm64: Emulate RAS error registers and set HCR_EL2's TERR & TEA KVM: arm64: Handle RAS SErrors from EL2 on guest exit KVM: arm64: Handle RAS SErrors from EL1 on guest exit KVM: arm64: Save ESR_EL2 on guest SError KVM: arm64: Save/Restore guest DISR_EL1 KVM: arm64: Set an impdef ESR for Virtual-SError using VSESR_EL2. KVM: arm/arm64: mask/unmask daif around VHE guests arm64: kernel: Prepare for a DISR user arm64: Unconditionally enable IESB on exception entry/return for firmware-first arm64: kernel: Survive corrected RAS errors notified by SError arm64: cpufeature: Detect CPU RAS Extentions arm64: sysreg: Move to use definitions for all the SCTLR bits arm64: cpufeature: __this_cpu_has_cap() shouldn't stop early ...
2018-01-26arm64: Fix TTBR + PAN + 52-bit PA logic in cpu_do_switch_mmSteve Capper1-3/+3
In cpu_do_switch_mm(.) with ARM64_SW_TTBR0_PAN=y we apply phys_to_ttbr to a value that already has an ASID inserted into the upper bits. For 52-bit PA configurations this then can give us TTBR0_EL1 registers that cause translation table walks to attempt to access non-zero PA[51:48] spuriously. Ultimately leading to a Synchronous External Abort on level 1 translation. This patch re-arranges the logic in cpu_do_switch_mm(.) such that phys_to_ttbr is called before the ASID is inserted into the TTBR0 value. Fixes: 6b88a32c7af6 ("arm64: kpti: Fix the interaction between ASID switching and software PAN") Acked-by: Suzuki K Poulose <suzuki.poulose@arm.com> Tested-by: Kristina Martsenko <kristina.martsenko@arm.com> Reviewed-by: Kristina Martsenko <kristina.martsenko@arm.com> Signed-off-by: Steve Capper <steve.capper@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-01-23arm64: Move BP hardening to check_and_switch_contextMarc Zyngier1-2/+3
We call arm64_apply_bp_hardening() from post_ttbr_update_workaround, which has the unexpected consequence of being triggered on every exception return to userspace when ARM64_SW_TTBR0_PAN is selected, even if no context switch actually occured. This is a bit suboptimal, and it would be more logical to only invalidate the branch predictor when we actually switch to a different mm. In order to solve this, move the call to arm64_apply_bp_hardening() into check_and_switch_context(), where we're guaranteed to pick a different mm context. Acked-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-01-19arm64: mm: ignore memory above supported physical address sizeKristina Martsenko1-0/+3
When booting a kernel without 52-bit PA support (e.g. a kernel with 4k pages) on a system with 52-bit memory, the kernel will currently try to use the 52-bit memory and crash. Fix this by ignoring any memory higher than what the kernel supports. Fixes: f77d281713d4 ("arm64: enable 52-bit physical address support") Signed-off-by: Kristina Martsenko <kristina.martsenko@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-01-17arm64: mm: Add additional parameter to uaccess_ttbr0_disableChristoffer Dall1-2/+2
Add an extra temporary register parameter to uaccess_ttbr0_disable which is about to be required for arm64 PAN support. This patch doesn't introduce any functional change but ensures that the kernel compiles once the KVM/ARM tree is merged with the arm64 tree by ensuring a trivially mergable conflict with commit 6b88a32c7af68895134872cdec3b6bfdb532d94e ("arm64: kpti: Fix the interaction between ASID switching and software PAN"). Cc: Will Deacon <will.deacon@arm.com> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2018-01-16arm64: kpti: Fix the interaction between ASID switching and software PANCatalin Marinas2-1/+4
With ARM64_SW_TTBR0_PAN enabled, the exception entry code checks the active ASID to decide whether user access was enabled (non-zero ASID) when the exception was taken. On return from exception, if user access was previously disabled, it re-instates TTBR0_EL1 from the per-thread saved value (updated in switch_mm() or efi_set_pgd()). Commit 7655abb95386 ("arm64: mm: Move ASID from TTBR0 to TTBR1") makes a TTBR0_EL1 + ASID switching non-atomic. Subsequently, commit 27a921e75711 ("arm64: mm: Fix and re-enable ARM64_SW_TTBR0_PAN") changes the __uaccess_ttbr0_disable() function and asm macro to first write the reserved TTBR0_EL1 followed by the ASID=0 update in TTBR1_EL1. If an exception occurs between these two, the exception return code will re-instate a valid TTBR0_EL1. Similar scenario can happen in cpu_switch_mm() between setting the reserved TTBR0_EL1 and the ASID update in cpu_do_switch_mm(). This patch reverts the entry.S check for ASID == 0 to TTBR0_EL1 and disables the interrupts around the TTBR0_EL1 and ASID switching code in __uaccess_ttbr0_disable(). It also ensures that, when returning from the EFI runtime services, efi_set_pgd() doesn't leave a non-zero ASID in TTBR1_EL1 by using uaccess_ttbr0_{enable,disable}. The accesses to current_thread_info()->ttbr0 are updated to use READ_ONCE/WRITE_ONCE. As a safety measure, __uaccess_ttbr0_enable() always masks out any existing non-zero ASID TTBR1_EL1 before writing in the new ASID. Fixes: 27a921e75711 ("arm64: mm: Fix and re-enable ARM64_SW_TTBR0_PAN") Acked-by: Will Deacon <will.deacon@arm.com> Reported-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Tested-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Reviewed-by: James Morse <james.morse@arm.com> Tested-by: James Morse <james.morse@arm.com> Co-developed-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-01-16arm64: kernel: Prepare for a DISR userJames Morse1-0/+5
KVM would like to consume any pending SError (or RAS error) after guest exit. Today it has to unmask SError and use dsb+isb to synchronise the CPU. With the RAS extensions we can use ESB to synchronise any pending SError. Add the necessary macros to allow DISR to be read and converted to an ESR. We clear the DISR register when we enable the RAS cpufeature, and the kernel has not executed any ESB instructions. Any value we find in DISR must have belonged to firmware. Executing an ESB instruction is the only way to update DISR, so we can expect firmware to have handled any deferred SError. By the same logic we clear DISR in the idle path. Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: James Morse <james.morse@arm.com> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-01-16arm64: sysreg: Move to use definitions for all the SCTLR bitsJames Morse1-23/+1
__cpu_setup() configures SCTLR_EL1 using some hard coded hex masks, and el2_setup() duplicates some this when setting RES1 bits. Lets make this the same as KVM's hyp_init, which uses named bits. First, we add definitions for all the SCTLR_EL{1,2} bits, the RES{1,0} bits, and those we want to set or clear. Add a build_bug checks to ensures all bits are either set or clear. This means we don't need to preserve endian-ness configuration generated elsewhere. Finally, move the head.S and proc.S users of these hard-coded masks over to the macro versions. Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-01-15arm64: Stop printing the virtual memory layoutLaura Abbott1-43/+0
Printing kernel addresses should be done in limited circumstances, mostly for debugging purposes. Printing out the virtual memory layout at every kernel bootup doesn't really fall into this category so delete the prints. There are other ways to get the same information. Acked-by: Kees Cook <keescook@chromium.org> Signed-off-by: Laura Abbott <labbott@redhat.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-01-15arm64: use swiotlb_alloc and swiotlb_freeChristoph Hellwig1-43/+3
The generic swiotlb_alloc and swiotlb_free routines already take care of CMA allocations and adding GFP_DMA32 where needed, so use them instead of the arm specific helpers. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Christian König <christian.koenig@amd.com> Reviewed-by: Robin Murphy <robin.murphy@arm.com>
2018-01-15arm64: replace ZONE_DMA with ZONE_DMA32Christoph Hellwig2-11/+11
arm64 uses ZONE_DMA for allocations below 32-bits. These days we name the zone for that ZONE_DMA32, which will allow to use the dma-direct and generic swiotlb code as-is, so rename it. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Christian König <christian.koenig@amd.com> Reviewed-by: Robin Murphy <robin.murphy@arm.com>
2018-01-15arm64: rename swiotlb_dma_opsChristoph Hellwig1-2/+2
We'll need that name for a generic implementation soon. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Christian König <christian.koenig@amd.com> Reviewed-by: Robin Murphy <robin.murphy@arm.com>
2018-01-14arm64: Extend early page table code to allow for larger kernelsSteve Capper1-1/+2
Currently the early assembler page table code assumes that precisely 1xpgd, 1xpud, 1xpmd are sufficient to represent the early kernel text mappings. Unfortunately this is rarely the case when running with a 16KB granule, and we also run into limits with 4KB granule when building much larger kernels. This patch re-writes the early page table logic to compute indices of mappings for each level of page table, and if multiple indices are required, the next-level page table is scaled up accordingly. Also the required size of the swapper_pg_dir is computed at link time to cover the mapping [KIMAGE_ADDR + VOFFSET, _end]. When KASLR is enabled, an extra page is set aside for each level that may require extra entries at runtime. Tested-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Steve Capper <steve.capper@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-01-14arm64: mmu: add the entry trampolines start/end section markers into sections.hJames Morse1-2/+0
SDEI needs to calculate an offset in the trampoline page too. Move the extern char[] to sections.h. This patch just moves code around. Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-01-13arm64: alternatives: use tpidr_el2 on VHE hostsJames Morse1-0/+8
Now that KVM uses tpidr_el2 in the same way as Linux's cpu_offset in tpidr_el1, merge the two. This saves KVM from save/restoring tpidr_el1 on VHE hosts, and allows future code to blindly access per-cpu variables without triggering world-switch. Signed-off-by: James Morse <james.morse@arm.com> Reviewed-by: Christoffer Dall <cdall@linaro.org> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-01-12signal/arm64: Document conflicts with SI_USER and SIGFPE,SIGTRAP,SIGBUSEric W. Biederman1-57/+57
Setting si_code to 0 results in a userspace seeing an si_code of 0. This is the same si_code as SI_USER. Posix and common sense requires that SI_USER not be a signal specific si_code. As such this use of 0 for the si_code is a pretty horribly broken ABI. Further use of si_code == 0 guaranteed that copy_siginfo_to_user saw a value of __SI_KILL and now sees a value of SIL_KILL with the result that uid and pid fields are copied and which might copying the si_addr field by accident but certainly not by design. Making this a very flakey implementation. Utilizing FPE_FIXME, BUS_FIXME, TRAP_FIXME siginfo_layout will now return SIL_FAULT and the appropriate fields will be reliably copied. But folks this is a new and unique kind of bad. This is massively untested code bad. This is inventing new and unique was to get siginfo wrong bad. This is don't even think about Posix or what siginfo means bad. This is lots of eyeballs all missing the fact that the code does the wrong thing bad. This is getting stuck and keep making the same mistake bad. I really hope we can find a non userspace breaking fix for this on a port as new as arm64. Possible ABI fixes include: - Send the signal without siginfo - Don't generate a signal - Possibly assign and use an appropriate si_code - Don't handle cases which can't happen Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will.deacon@arm.com> Cc: Tyler Baicar <tbaicar@codeaurora.org> Cc: James Morse <james.morse@arm.com> Cc: Tony Lindgren <tony@atomide.com> Cc: Nicolas Pitre <nico@linaro.org> Cc: Olof Johansson <olof@lixom.net> Cc: Santosh Shilimkar <santosh.shilimkar@ti.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: linux-arm-kernel@lists.infradead.org Ref: 53631b54c870 ("arm64: Floating point and SIMD") Ref: 32015c235603 ("arm64: exception: handle Synchronous External Abort") Ref: 1d18c47c735e ("arm64: MMU fault handling and page table management") Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2018-01-10dma-mapping: move swiotlb arch helpers to a new headerChristoph Hellwig1-1/+1
phys_to_dma, dma_to_phys and dma_capable are helpers published by architecture code for use of swiotlb and xen-swiotlb only. Drivers are not supposed to use these directly, but use the DMA API instead. Move these to a new asm/dma-direct.h helper, included by a linux/dma-direct.h wrapper that provides the default linear mapping unless the architecture wants to override it. In the MIPS case the existing dma-coherent.h is reused for now as untangling it will take a bit of work. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Robin Murphy <robin.murphy@arm.com>