user/sven/linux.git/drivers/firmware/efi, branch v4.10.4

efi/arm: Fix boot crash with CONFIG_CPUMASK_OFFSTACK=y

2017-03-18T11:18:39Z

commit d1eb98143c56f24fef125f5bbed49ae0b52fb7d6 upstream. On ARM and arm64, we use a dedicated mm_struct to map the UEFI Runtime Services regions, which allows us to map those regions on demand, and in a way that is guaranteed to be compatible with incoming kernels across kexec. As it turns out, we don't fully initialize the mm_struct in the same way as process mm_structs are initialized on fork(), which results in the following crash on ARM if CONFIG_CPUMASK_OFFSTACK=y is enabled: ... EFI Variables Facility v0.08 2004-May-17 Unable to handle kernel NULL pointer dereference at virtual address 00000000 [...] Process swapper/0 (pid: 1) ... __memzero() check_and_switch_context() virt_efi_get_next_variable() efivar_init() efivars_sysfs_init() do_one_initcall() ... This is due to a missing call to mm_init_cpumask(), so add it. Signed-off-by: Ard Biesheuvel Cc: Linus Torvalds Cc: Matt Fleming Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: linux-efi@vger.kernel.org Link: http://lkml.kernel.org/r/1488395154-29786-1-git-send-email-ard.biesheuvel@linaro.org Signed-off-by: Ingo Molnar Signed-off-by: Greg Kroah-Hartman

efi/fdt: Avoid FDT manipulation after ExitBootServices()

2017-02-01T20:17:49Z

Some AArch64 UEFI implementations disable the MMU in ExitBootServices(), after which unaligned accesses to RAM are no longer supported. Commit: abfb7b686a3e ("efi/libstub/arm*: Pass latest memory map to the kernel") fixed an issue in the memory map handling of the stub FDT code, but inadvertently created an issue with such firmware, by moving some of the FDT manipulation to after the invocation of ExitBootServices(). Given that the stub's libfdt implementation uses the ordinary, accelerated string functions, which rely on hardware handling of unaligned accesses, manipulating the FDT with the MMU off may result in alignment faults. So fix the situation by moving the update_fdt_memmap() call into the callback function invoked by efi_exit_boot_services() right before it calls the ExitBootServices() UEFI service (which is arguably a better place for it anyway) Note that disabling the MMU in ExitBootServices() is not compliant with the UEFI spec, and carries great risk due to the fact that switching from cached to uncached memory accesses halfway through compiler generated code (i.e., involving a stack) can never be done in a way that is architecturally safe. Fixes: abfb7b686a3e ("efi/libstub/arm*: Pass latest memory map to the kernel") Signed-off-by: Ard Biesheuvel Tested-by: Riku Voipio Cc: Cc: mark.rutland@arm.com Cc: linux-efi@vger.kernel.org Cc: matt@codeblueprint.co.uk Cc: leif.lindholm@linaro.org Cc: linux-arm-kernel@lists.infradead.org Link: http://lkml.kernel.org/r/1485971102-23330-2-git-send-email-ard.biesheuvel@linaro.org Signed-off-by: Ingo Molnar

x86/efi: Don't allocate memmap through memblock after mm_init()

2017-01-07T07:58:07Z

With the following commit: 4bc9f92e64c8 ("x86/efi-bgrt: Use efi_mem_reserve() to avoid copying image data") ... efi_bgrt_init() calls into the memblock allocator through efi_mem_reserve() => efi_arch_mem_reserve() *after* mm_init() has been called. Indeed, KASAN reports a bad read access later on in efi_free_boot_services(): BUG: KASAN: use-after-free in efi_free_boot_services+0xae/0x24c at addr ffff88022de12740 Read of size 4 by task swapper/0/0 page:ffffea0008b78480 count:0 mapcount:-127 mapping: (null) index:0x1 flags: 0x5fff8000000000() [...] Call Trace: dump_stack+0x68/0x9f kasan_report_error+0x4c8/0x500 kasan_report+0x58/0x60 __asan_load4+0x61/0x80 efi_free_boot_services+0xae/0x24c start_kernel+0x527/0x562 x86_64_start_reservations+0x24/0x26 x86_64_start_kernel+0x157/0x17a start_cpu+0x5/0x14 The instruction at the given address is the first read from the memmap's memory, i.e. the read of md->type in efi_free_boot_services(). Note that the writes earlier in efi_arch_mem_reserve() don't splat because they're done through early_memremap()ed addresses. So, after memblock is gone, allocations should be done through the "normal" page allocator. Introduce a helper, efi_memmap_alloc() for this. Use it from efi_arch_mem_reserve(), efi_free_boot_services() and, for the sake of consistency, from efi_fake_memmap() as well. Note that for the latter, the memmap allocations cease to be page aligned. This isn't needed though. Tested-by: Dan Williams Signed-off-by: Nicolai Stange Reviewed-by: Ard Biesheuvel Cc: # v4.9 Cc: Dave Young Cc: Linus Torvalds Cc: Matt Fleming Cc: Mika Penttilä Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: linux-efi@vger.kernel.org Fixes: 4bc9f92e64c8 ("x86/efi-bgrt: Use efi_mem_reserve() to avoid copying image data") Link: http://lkml.kernel.org/r/20170105125130.2815-1-nicstange@gmail.com Signed-off-by: Ingo Molnar

efi/libstub/arm*: Pass latest memory map to the kernel

2016-12-28T08:23:32Z

As reported by James Morse, the current libstub code involving the annotated memory map only works somewhat correctly by accident, due to the fact that a pool allocation happens to be reused immediately, retaining its former contents on most implementations of the UEFI boot services. Instead of juggling memory maps, which makes the code more complex than it needs to be, simply put placeholder values into the FDT for the memory map parameters, and only write the actual values after ExitBootServices() has been called. Reported-by: James Morse Signed-off-by: Ard Biesheuvel Cc: Cc: Jeffrey Hugo Cc: Linus Torvalds Cc: Matt Fleming Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: linux-arm-kernel@lists.infradead.org Cc: linux-efi@vger.kernel.org Fixes: ed9cc156c42f ("efi/libstub: Use efi_exit_boot_services() in FDT") Link: http://lkml.kernel.org/r/1482587963-20183-2-git-send-email-ard.biesheuvel@linaro.org Signed-off-by: Ingo Molnar

Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial

2016-12-14T19:12:25Z

Pull trivial updates from Jiri Kosina. * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: NTB: correct ntb_spad_count comment typo misc: ibmasm: fix typo in error message Remove references to dead make variable LINUX_INCLUDE Remove last traces of ikconfig.h treewide: Fix printk() message errors Documentation/device-mapper: s/getsize/getsz/

Remove references to dead make variable LINUX_INCLUDE

2016-12-14T09:54:28Z

Commit 4fd06960f120 ("Use the new x86 setup code for i386") introduced a reference to the make variable LINUX_INCLUDE. That reference got moved around a bit and copied twice and now there are three references to it. There has never been a definition of that variable. (Presumably that is because it started out as a mistyped reference to LINUXINCLUDE.) So this reference has always been an empty string. Let's remove it before it spreads any further. Signed-off-by: Paul Bolle Signed-off-by: Jiri Kosina

Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux

2016-12-14T00:39:21Z

Pull arm64 updates from Catalin Marinas: - struct thread_info moved off-stack (also touching include/linux/thread_info.h and include/linux/restart_block.h) - cpus_have_cap() reworked to avoid __builtin_constant_p() for static key use (also touching drivers/irqchip/irq-gic-v3.c) - uprobes support (currently only for native 64-bit tasks) - Emulation of kernel Privileged Access Never (PAN) using TTBR0_EL1 switching to a reserved page table - CPU capacity information passing via DT or sysfs (used by the scheduler) - support for systems without FP/SIMD (IOW, kernel avoids touching these registers; there is no soft-float ABI, nor kernel emulation for AArch64 FP/SIMD) - handling of hardware watchpoint with unaligned addresses, varied lengths and offsets from base - use of the page table contiguous hint for kernel mappings - hugetlb fixes for sizes involving the contiguous hint - remove unnecessary I-cache invalidation in flush_cache_range() - CNTHCTL_EL2 access fix for CPUs with VHE support (ARMv8.1) - boot-time checks for writable+executable kernel mappings - simplify asm/opcodes.h and avoid including the 32-bit ARM counterpart and make the arm64 kernel headers self-consistent (Xen headers patch merged separately) - Workaround for broken .inst support in certain binutils versions * tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (60 commits) arm64: Disable PAN on uaccess_enable() arm64: Work around broken .inst when defective gas is detected arm64: Add detection code for broken .inst support in binutils arm64: Remove reference to asm/opcodes.h arm64: Get rid of asm/opcodes.h arm64: smp: Prevent raw_smp_processor_id() recursion arm64: head.S: Fix CNTHCTL_EL2 access on VHE system arm64: Remove I-cache invalidation from flush_cache_range() arm64: Enable HIBERNATION in defconfig arm64: Enable CONFIG_ARM64_SW_TTBR0_PAN arm64: xen: Enable user access before a privcmd hvc call arm64: Handle faults caused by inadvertent user access with PAN enabled arm64: Disable TTBR0_EL1 during normal kernel execution arm64: Introduce uaccess_{disable,enable} functionality based on TTBR0_EL1 arm64: Factor out TTBR0_EL1 post-update workaround into a specific asm macro arm64: Factor out PAN enabling/disabling into separate uaccess_* macros arm64: Update the synchronous external abort fault description selftests: arm64: add test for unaligned/inexact watchpoint handling arm64: Allow hw watchpoint of length 3,5,6 and 7 arm64: hw_breakpoint: Handle inexact watchpoint addresses ...

efi/libstub: Make efi_random_alloc() allocate below 4 GB on 32-bit

2016-11-25T06:15:23Z

The UEFI stub executes in the context of the firmware, which identity maps the available system RAM, which implies that only memory below 4 GB can be used for allocations on 32-bit architectures, even on [L]PAE capable hardware. So ignore any reported memory above 4 GB in efi_random_alloc(). This also fixes a reported build problem on ARM under -Os, where the 64-bit logical shift relies on a software routine that the ARM decompressor does not provide. A second [minor] issue is also fixed, where the '+ 1' is moved out of the shift, where it belongs: the reason for its presence is that a memory region where start == end should count as a single slot, given that 'end' takes the desired size and alignment of the allocation into account. To clarify the code in this regard, rename start/end to 'first_slot' and 'last_slot', respectively, and introduce 'region_end' to describe the last usable address of the current region. Reported-by: Arnd Bergmann Signed-off-by: Ard Biesheuvel Cc: Linus Torvalds Cc: Matt Fleming Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: linux-efi@vger.kernel.org Link: http://lkml.kernel.org/r/1480010543-25709-2-git-send-email-ard.biesheuvel@linaro.org Signed-off-by: Ingo Molnar

x86/efi: Retrieve and assign Apple device properties

2016-11-13T07:23:16Z

Apple's EFI drivers supply device properties which are needed to support Macs optimally. They contain vital information which cannot be obtained any other way (e.g. Thunderbolt Device ROM). They're also used to convey the current device state so that OS drivers can pick up where EFI drivers left (e.g. GPU mode setting). There's an EFI driver dubbed "AAPL,PathProperties" which implements a per-device key/value store. Other EFI drivers populate it using a custom protocol. The macOS bootloader /System/Library/CoreServices/boot.efi retrieves the properties with the same protocol. The kernel extension AppleACPIPlatform.kext subsequently merges them into the I/O Kit registry (see ioreg(8)) where they can be queried by other kernel extensions and user space. This commit extends the efistub to retrieve the device properties before ExitBootServices is called. It assigns them to devices in an fs_initcall so that they can be queried with the API in . Note that the device properties will only be available if the kernel is booted with the efistub. Distros should adjust their installers to always use the efistub on Macs. grub with the "linux" directive will not work unless the functionality of this commit is duplicated in grub. (The "linuxefi" directive should work but is not included upstream as of this writing.) The custom protocol has GUID 91BD12FE-F6C3-44FB-A5B7-5122AB303AE0 and looks like this: typedef struct { unsigned long version; /* 0x10000 */ efi_status_t (*get) ( IN struct apple_properties_protocol *this, IN struct efi_dev_path *device, IN efi_char16_t *property_name, OUT void *buffer, IN OUT u32 *buffer_len); /* EFI_SUCCESS, EFI_NOT_FOUND, EFI_BUFFER_TOO_SMALL */ efi_status_t (*set) ( IN struct apple_properties_protocol *this, IN struct efi_dev_path *device, IN efi_char16_t *property_name, IN void *property_value, IN u32 property_value_len); /* allocates copies of property name and value */ /* EFI_SUCCESS, EFI_OUT_OF_RESOURCES */ efi_status_t (*del) ( IN struct apple_properties_protocol *this, IN struct efi_dev_path *device, IN efi_char16_t *property_name); /* EFI_SUCCESS, EFI_NOT_FOUND */ efi_status_t (*get_all) ( IN struct apple_properties_protocol *this, OUT void *buffer, IN OUT u32 *buffer_len); /* EFI_SUCCESS, EFI_BUFFER_TOO_SMALL */ } apple_properties_protocol; Thanks to Pedro Vilaça for this blog post which was helpful in reverse engineering Apple's EFI drivers and bootloader: https://reverse.put.as/2016/06/25/apple-efi-firmware-passwords-and-the-scbo-myth/ If someone at Apple is reading this, please note there's a memory leak in your implementation of the del() function as the property struct is freed but the name and value allocations are not. Neither the macOS bootloader nor Apple's EFI drivers check the protocol version, but we do to avoid breakage if it's ever changed. It's been the same since at least OS X 10.6 (2009). The get_all() function conveniently fills a buffer with all properties in marshalled form which can be passed to the kernel as a setup_data payload. The number of device properties is dynamic and can change between a first invocation of get_all() (to determine the buffer size) and a second invocation (to retrieve the actual buffer), hence the peculiar loop which does not finish until the buffer size settles. The macOS bootloader does the same. The setup_data payload is later on unmarshalled in an fs_initcall. The idea is that most buses instantiate devices in "subsys" initcall level and drivers are usually bound to these devices in "device" initcall level, so we assign the properties in-between, i.e. in "fs" initcall level. This assumes that devices to which properties pertain are instantiated from a "subsys" initcall or earlier. That should always be the case since on macOS, AppleACPIPlatformExpert::matchEFIDevicePath() only supports ACPI and PCI nodes and we've fully scanned those buses during "subsys" initcall level. The second assumption is that properties are only needed from a "device" initcall or later. Seems reasonable to me, but should this ever not work out, an alternative approach would be to store the property sets e.g. in a btree early during boot. Then whenever device_add() is called, an EFI Device Path would have to be constructed for the newly added device, and looked up in the btree. That way, the property set could be assigned to the device immediately on instantiation. And this would also work for devices instantiated in a deferred fashion. It seems like this approach would be more complicated and require more code. That doesn't seem justified without a specific use case. For comparison, the strategy on macOS is to assign properties to objects in the ACPI namespace (AppleACPIPlatformExpert::mergeEFIProperties()). That approach is definitely wrong as it fails for devices not present in the namespace: The NHI EFI driver supplies properties for attached Thunderbolt devices, yet on Macs with Thunderbolt 1 only one device level behind the host controller is described in the namespace. Consequently macOS cannot assign properties for chained devices. With Thunderbolt 2 they started to describe three device levels behind host controllers in the namespace but this grossly inflates the SSDT and still fails if the user daisy-chained more than three devices. We copy the property names and values from the setup_data payload to swappable virtual memory and afterwards make the payload available to the page allocator. This is just for the sake of good housekeeping, it wouldn't occupy a meaningful amount of physical memory (4444 bytes on my machine). Only the payload is freed, not the setup_data header since otherwise we'd break the list linkage and we cannot safely update the predecessor's ->next link because there's no locking for the list. The payload is currently not passed on to kexec'ed kernels, same for PCI ROMs retrieved by setup_efi_pci(). This can be added later if there is demand by amending setup_efi_state(). The payload can then no longer be made available to the page allocator of course. Tested-by: Lukas Wunner [MacBookPro9,1] Tested-by: Pierre Moreau [MacBookPro11,3] Signed-off-by: Lukas Wunner Signed-off-by: Matt Fleming Cc: Andreas Noever Cc: Ard Biesheuvel Cc: Linus Torvalds Cc: Pedro Vilaça Cc: Peter Jones Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: grub-devel@gnu.org Cc: linux-efi@vger.kernel.org Link: http://lkml.kernel.org/r/20161112213237.8804-9-matt@codeblueprint.co.uk Signed-off-by: Ingo Molnar

efi: Add device path parser

2016-11-13T07:23:15Z

We're about to extended the efistub to retrieve device properties from EFI on Apple Macs. The properties use EFI Device Paths to indicate the device they belong to. This commit adds a parser which, given an EFI Device Path, locates the corresponding struct device and returns a reference to it. Initially only ACPI and PCI Device Path nodes are supported, these are the only types needed for Apple device properties (the corresponding macOS function AppleACPIPlatformExpert::matchEFIDevicePath() does not support any others). Further node types can be added with little to moderate effort. Apple device properties is currently the only use case of this parser, but Peter Jones intends to use it to match up devices with the ConInDev/ConOutDev/ErrOutDev variables and add sysfs attributes to these devices to say the hardware supports using them as console. Thus, make this parser a separate component which can be selected with config option EFI_DEV_PATH_PARSER. It can in principle be compiled as a module if acpi_get_first_physical_node() and acpi_bus_type are exported (and efi_get_device_by_path() itself is exported). The dependency on CONFIG_ACPI is needed for acpi_match_device_ids(). It can be removed if an empty inline stub is added for that function. Signed-off-by: Lukas Wunner Signed-off-by: Matt Fleming Cc: Andreas Noever Cc: Ard Biesheuvel Cc: Linus Torvalds Cc: Peter Jones Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: linux-efi@vger.kernel.org Link: http://lkml.kernel.org/r/20161112213237.8804-7-matt@codeblueprint.co.uk Signed-off-by: Ingo Molnar