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2020-01-29Merge tag 'char-misc-5.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-miscLinus Torvalds3-2/+34
Pull char/misc driver updates from Greg KH: "Here is the big char/misc/whatever driver changes for 5.6-rc1 Included in here are loads of things from a variety of different driver subsystems: - soundwire updates - binder updates - nvmem updates - firmware drivers updates - extcon driver updates - various misc driver updates - fpga driver updates - interconnect subsystem and driver updates - bus driver updates - uio driver updates - mei driver updates - w1 driver cleanups - various other small driver updates All of these have been in linux-next for a while with no reported issues" * tag 'char-misc-5.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (86 commits) mei: me: add jasper point DID char: hpet: Use flexible-array member binder: fix log spam for existing debugfs file creation. mei: me: add comet point (lake) H device ids nvmem: add QTI SDAM driver dt-bindings: nvmem: add binding for QTI SPMI SDAM dt-bindings: imx-ocotp: Add i.MX8MP compatible dt-bindings: soundwire: fix example soundwire: cadence: fix kernel-doc parameter descriptions soundwire: intel: report slave_ids for each link to SOF driver siox: Use the correct style for SPDX License Identifier w1: omap-hdq: Simplify driver with PM runtime autosuspend firmware: stratix10-svc: Remove unneeded semicolon firmware: google: Probe for a GSMI handler in firmware firmware: google: Unregister driver_info on failure and exit in gsmi firmware: google: Release devices before unregistering the bus slimbus: qcom: add missed clk_disable_unprepare in remove slimbus: Use the correct style for SPDX License Identifier slimbus: qcom-ngd-ctrl: Use dma_request_chan() instead dma_request_slave_channel() dt-bindings: SLIMBus: add slim devices optional properties ...
2020-01-28Merge branch 'efi-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds17-583/+704
Pull EFI updates from Ingo Molnar: "The main changes in this cycle were: - Cleanup of the GOP [graphics output] handling code in the EFI stub - Complete refactoring of the mixed mode handling in the x86 EFI stub - Overhaul of the x86 EFI boot/runtime code - Increase robustness for mixed mode code - Add the ability to disable DMA at the root port level in the EFI stub - Get rid of RWX mappings in the EFI memory map and page tables, where possible - Move the support code for the old EFI memory mapping style into its only user, the SGI UV1+ support code. - plus misc fixes, updates, smaller cleanups. ... and due to interactions with the RWX changes, another round of PAT cleanups make a guest appearance via the EFI tree - with no side effects intended" * 'efi-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (75 commits) efi/x86: Disable instrumentation in the EFI runtime handling code efi/libstub/x86: Fix EFI server boot failure efi/x86: Disallow efi=old_map in mixed mode x86/boot/compressed: Relax sed symbol type regex for LLVM ld.lld efi/x86: avoid KASAN false positives when accessing the 1: 1 mapping efi: Fix handling of multiple efi_fake_mem= entries efi: Fix efi_memmap_alloc() leaks efi: Add tracking for dynamically allocated memmaps efi: Add a flags parameter to efi_memory_map efi: Fix comment for efi_mem_type() wrt absent physical addresses efi/arm: Defer probe of PCIe backed efifb on DT systems efi/x86: Limit EFI old memory map to SGI UV machines efi/x86: Avoid RWX mappings for all of DRAM efi/x86: Don't map the entire kernel text RW for mixed mode x86/mm: Fix NX bit clearing issue in kernel_map_pages_in_pgd efi/libstub/x86: Fix unused-variable warning efi/libstub/x86: Use mandatory 16-byte stack alignment in mixed mode efi/libstub/x86: Use const attribute for efi_is_64bit() efi: Allow disabling PCI busmastering on bridges during boot efi/x86: Allow translating 64-bit arguments for mixed mode calls ...
2020-01-28Merge branch 'core-headers-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds1-0/+1
Pull header cleanup from Ingo Molnar: "This is a treewide cleanup, mostly (but not exclusively) with x86 impact, which breaks implicit dependencies on the asm/realtime.h header and finally removes it from asm/acpi.h" * 'core-headers-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/ACPI/sleep: Move acpi_get_wakeup_address() into sleep.c, remove <asm/realmode.h> from <asm/acpi.h> ACPI/sleep: Convert acpi_wakeup_address into a function x86/ACPI/sleep: Remove an unnecessary include of asm/realmode.h ASoC: Intel: Skylake: Explicitly include linux/io.h for virt_to_phys() vmw_balloon: Explicitly include linux/io.h for virt_to_phys() virt: vbox: Explicitly include linux/io.h to pick up various defs efi/capsule-loader: Explicitly include linux/io.h for page_to_phys() perf/x86/intel: Explicitly include asm/io.h to use virt_to_phys() x86/kprobes: Explicitly include vmalloc.h for set_vm_flush_reset_perms() x86/ftrace: Explicitly include vmalloc.h for set_vm_flush_reset_perms() x86/boot: Explicitly include realmode.h to handle RM reservations x86/efi: Explicitly include realmode.h to handle RM trampoline quirk x86/platform/intel/quark: Explicitly include linux/io.h for virt_to_phys() x86/setup: Enhance the comments x86/setup: Clean up the header portion of setup.c
2020-01-27Merge tag 'ioremap-5.6' of git://git.infradead.org/users/hch/ioremapLinus Torvalds1-1/+1
Pull ioremap updates from Christoph Hellwig: "Remove the ioremap_nocache API (plus wrappers) that are always identical to ioremap" * tag 'ioremap-5.6' of git://git.infradead.org/users/hch/ioremap: remove ioremap_nocache and devm_ioremap_nocache MIPS: define ioremap_nocache to ioremap
2020-01-22Merge 5.5-rc7 into char-misc-nextGreg Kroah-Hartman2-12/+10
We need the char-misc fixes in here as well. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-01-20efi: Fix handling of multiple efi_fake_mem= entriesDan Williams2-16/+17
Dave noticed that when specifying multiple efi_fake_mem= entries only the last entry was successfully being reflected in the efi memory map. This is due to the fact that the efi_memmap_insert() is being called multiple times, but on successive invocations the insertion should be applied to the last new memmap rather than the original map at efi_fake_memmap() entry. Rework efi_fake_memmap() to install the new memory map after each efi_fake_mem= entry is parsed. This also fixes an issue in efi_fake_memmap() that caused it to litter emtpy entries into the end of the efi memory map. An empty entry causes efi_memmap_insert() to attempt more memmap splits / copies than efi_memmap_split_count() accounted for when sizing the new map. When that happens efi_memmap_insert() may overrun its allocation, and if you are lucky will spill over to an unmapped page leading to crash signature like the following rather than silent corruption: BUG: unable to handle page fault for address: ffffffffff281000 [..] RIP: 0010:efi_memmap_insert+0x11d/0x191 [..] Call Trace: ? bgrt_init+0xbe/0xbe ? efi_arch_mem_reserve+0x1cb/0x228 ? acpi_parse_bgrt+0xa/0xd ? acpi_table_parse+0x86/0xb8 ? acpi_boot_init+0x494/0x4e3 ? acpi_parse_x2apic+0x87/0x87 ? setup_acpi_sci+0xa2/0xa2 ? setup_arch+0x8db/0x9e1 ? start_kernel+0x6a/0x547 ? secondary_startup_64+0xb6/0xc0 Commit af1648984828 "x86/efi: Update e820 with reserved EFI boot services data to fix kexec breakage" introduced more occurrences where efi_memmap_insert() is invoked after an efi_fake_mem= configuration has been parsed. Previously the side effects of vestigial empty entries were benign, but with commit af1648984828 that follow-on efi_memmap_insert() invocation triggers efi_memmap_insert() overruns. Reported-by: Dave Young <dyoung@redhat.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Link: https://lore.kernel.org/r/20191231014630.GA24942@dhcp-128-65.nay.redhat.com Link: https://lore.kernel.org/r/20200113172245.27925-14-ardb@kernel.org
2020-01-20efi: Fix efi_memmap_alloc() leaksDan Williams1-0/+25
With efi_fake_memmap() and efi_arch_mem_reserve() the efi table may be updated and replaced multiple times. When that happens a previous dynamically allocated efi memory map can be garbage collected. Use the new EFI_MEMMAP_{SLAB,MEMBLOCK} flags to detect when a dynamically allocated memory map is being replaced. Debug statements in efi_memmap_free() reveal: efi: __efi_memmap_free:37: phys: 0x23ffdd580 size: 2688 flags: 0x2 efi: __efi_memmap_free:37: phys: 0x9db00 size: 2640 flags: 0x2 efi: __efi_memmap_free:37: phys: 0x9e580 size: 2640 flags: 0x2 ...a savings of 7968 bytes on a qemu boot with 2 entries specified to efi_fake_mem=. [ ardb: added a comment to clarify that efi_memmap_free() does nothing when called from efi_clean_memmap(), i.e., with data->flags == 0x0 ] Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Link: https://lore.kernel.org/r/20200113172245.27925-13-ardb@kernel.org
2020-01-20efi: Add tracking for dynamically allocated memmapsDan Williams2-29/+32
In preparation for fixing efi_memmap_alloc() leaks, add support for recording whether the memmap was dynamically allocated from slab, memblock, or is the original physical memmap provided by the platform. Given this tracking is established in efi_memmap_alloc() and needs to be carried to efi_memmap_install(), use 'struct efi_memory_map_data' to convey the flags. Some small cleanups result from this reorganization, specifically the removal of local variables for 'phys' and 'size' that are already tracked in @data. Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Link: https://lore.kernel.org/r/20200113172245.27925-12-ardb@kernel.org
2020-01-20efi: Add a flags parameter to efi_memory_mapDan Williams1-14/+17
In preparation for garbage collecting dynamically allocated EFI memory maps, where the allocation method of memblock vs slab needs to be recalled, convert the existing 'late' flag into a 'flags' bitmask. Arrange for the flag to be passed via 'struct efi_memory_map_data'. This structure grows additional flags in follow-on changes. Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Link: https://lore.kernel.org/r/20200113172245.27925-11-ardb@kernel.org
2020-01-20efi: Fix comment for efi_mem_type() wrt absent physical addressesAnshuman Khandual1-1/+1
A previous commit f99afd08a45f ("efi: Update efi_mem_type() to return an error rather than 0") changed the return value from EFI_RESERVED_TYPE to -EINVAL when the searched physical address is not present in any memory descriptor. But the comment preceding the function never changed. Let's change the comment now to reflect the new return value -EINVAL. Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com> Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Link: https://lore.kernel.org/r/20200113172245.27925-10-ardb@kernel.org
2020-01-20efi/arm: Defer probe of PCIe backed efifb on DT systemsArd Biesheuvel1-4/+103
The new of_devlink support breaks PCIe probing on ARM platforms booting via UEFI if the firmware exposes a EFI framebuffer that is backed by a PCI device. The reason is that the probing order gets reversed, resulting in a resource conflict on the framebuffer memory window when the PCIe probes last, causing it to give up entirely. Given that we rely on PCI quirks to deal with EFI framebuffers that get moved around in memory, we cannot simply drop the memory reservation, so instead, let's use the device link infrastructure to register this dependency, and force the probing to occur in the expected order. Co-developed-by: Saravana Kannan <saravanak@google.com> Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Signed-off-by: Saravana Kannan <saravanak@google.com> Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Link: https://lore.kernel.org/r/20200113172245.27925-9-ardb@kernel.org
2020-01-18Merge branch 'efi-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds2-12/+10
Pull EFI fixes from Ingo Molnar: "Three EFI fixes: - Fix a slow-boot-scrolling regression but making sure we use WC for EFI earlycon framebuffer mappings on x86 - Fix a mixed EFI mode boot crash - Disable paging explicitly before entering startup_32() in mixed mode bootup" * 'efi-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/efistub: Disable paging at mixed mode entry efi/libstub/random: Initialize pointer variables to zero for mixed mode efi/earlycon: Fix write-combine mapping on x86
2020-01-14firmware: stratix10-svc: Remove unneeded semicolonzhengbin1-2/+2
Fixes coccicheck warning: drivers/firmware/stratix10-svc.c:271:2-3: Unneeded semicolon drivers/firmware/stratix10-svc.c:515:2-3: Unneeded semicolon Reported-by: Hulk Robot <hulkci@huawei.com> Signed-off-by: zhengbin <zhengbin13@huawei.com> Link: https://lore.kernel.org/r/1576465378-11109-1-git-send-email-zhengbin13@huawei.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-01-14firmware: google: Probe for a GSMI handler in firmwareArthur Heymans1-0/+19
Currently this driver is loaded if the DMI string matches coreboot and has a proper smi_command in the ACPI FADT table, but a GSMI handler in SMM is an optional feature in coreboot. So probe for a SMM GSMI handler before initializing the driver. If the smihandler leaves the calling argument in %eax in the SMM save state untouched that generally means the is no handler for GSMI. Signed-off-by: Arthur Heymans <arthur@aheymans.xyz> Signed-off-by: Patrick Rudolph <patrick.rudolph@9elements.com> Link: https://lore.kernel.org/r/20191118101934.22526-4-patrick.rudolph@9elements.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-01-14firmware: google: Unregister driver_info on failure and exit in gsmiArthur Heymans1-0/+6
Fix a bug where the kernel module couldn't be loaded after unloading, as the platform driver wasn't released on exit. Signed-off-by: Arthur Heymans <arthur@aheymans.xyz> Signed-off-by: Patrick Rudolph <patrick.rudolph@9elements.com> Link: https://lore.kernel.org/r/20191118101934.22526-3-patrick.rudolph@9elements.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-01-14firmware: google: Release devices before unregistering the busPatrick Rudolph1-0/+7
Fix a bug where the kernel module can't be loaded after it has been unloaded as the devices are still present and conflicting with the to be created coreboot devices. Signed-off-by: Patrick Rudolph <patrick.rudolph@9elements.com> Link: https://lore.kernel.org/r/20191118101934.22526-2-patrick.rudolph@9elements.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-01-10efi: Allow disabling PCI busmastering on bridges during bootMatthew Garrett4-1/+152
Add an option to disable the busmaster bit in the control register on all PCI bridges before calling ExitBootServices() and passing control to the runtime kernel. System firmware may configure the IOMMU to prevent malicious PCI devices from being able to attack the OS via DMA. However, since firmware can't guarantee that the OS is IOMMU-aware, it will tear down IOMMU configuration when ExitBootServices() is called. This leaves a window between where a hostile device could still cause damage before Linux configures the IOMMU again. If CONFIG_EFI_DISABLE_PCI_DMA is enabled or "efi=disable_early_pci_dma" is passed on the command line, the EFI stub will clear the busmaster bit on all PCI bridges before ExitBootServices() is called. This will prevent any malicious PCI devices from being able to perform DMA until the kernel reenables busmastering after configuring the IOMMU. This option may cause failures with some poorly behaved hardware and should not be enabled without testing. The kernel commandline options "efi=disable_early_pci_dma" or "efi=no_disable_early_pci_dma" may be used to override the default. Note that PCI devices downstream from PCI bridges are disconnected from their drivers first, using the UEFI driver model API, so that DMA can be disabled safely at the bridge level. [ardb: disconnect PCI I/O handles first, as suggested by Arvind] Co-developed-by: Matthew Garrett <mjg59@google.com> Signed-off-by: Matthew Garrett <mjg59@google.com> Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Cc: Andy Lutomirski <luto@kernel.org> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Arvind Sankar <nivedita@alum.mit.edu> Cc: Matthew Garrett <matthewgarrett@google.com> Cc: linux-efi@vger.kernel.org Link: https://lkml.kernel.org/r/20200103113953.9571-18-ardb@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2020-01-10efi/x86: Allow translating 64-bit arguments for mixed mode callsArvind Sankar1-4/+1
Introduce the ability to define macros to perform argument translation for the calls that need it, and define them for the boot services that we currently use. When calling 32-bit firmware methods in mixed mode, all output parameters that are 32-bit according to the firmware, but 64-bit in the kernel (ie OUT UINTN * or OUT VOID **) must be initialized in the kernel, or the upper 32 bits may contain garbage. Define macros that zero out the upper 32 bits of the output before invoking the firmware method. When a 32-bit EFI call takes 64-bit arguments, the mixed-mode call must push the two 32-bit halves as separate arguments onto the stack. This can be achieved by splitting the argument into its two halves when calling the assembler thunk. Define a macro to do this for the free_pages boot service. Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu> Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Cc: Andy Lutomirski <luto@kernel.org> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Matthew Garrett <mjg59@google.com> Cc: linux-efi@vger.kernel.org Link: https://lkml.kernel.org/r/20200103113953.9571-17-ardb@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2020-01-10Merge branch 'linus' into efi/core, to pick up fixesIngo Molnar1-1/+0
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2020-01-06firmware: tee_bnxt: Fix multiple call to tee_client_close_contextVikas Gupta1-1/+0
Fix calling multiple tee_client_close_context in case of shm allocation fails. Fixes: 246880958ac9 (“firmware: broadcom: add OP-TEE based BNXT f/w manager”) Signed-off-by: Vikas Gupta <vikas.gupta@broadcom.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-01-06remove ioremap_nocache and devm_ioremap_nocacheChristoph Hellwig1-1/+1
ioremap has provided non-cached semantics by default since the Linux 2.6 days, so remove the additional ioremap_nocache interface. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Arnd Bergmann <arnd@arndb.de>
2019-12-25efi/libstub: Tidy up types and names of global cmdline variablesArd Biesheuvel3-22/+28
Drop leading underscores and use bool not int for true/false variables set on the command line. Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Cc: Arvind Sankar <nivedita@alum.mit.edu> Cc: Borislav Petkov <bp@alien8.de> Cc: James Morse <james.morse@arm.com> Cc: Matt Fleming <matt@codeblueprint.co.uk> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-efi@vger.kernel.org Link: https://lkml.kernel.org/r/20191224151025.32482-25-ardb@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-12-25efi/libstub: Rename efi_call_early/_runtime macros to be more intuitiveArd Biesheuvel9-109/+90
The macros efi_call_early and efi_call_runtime are used to call EFI boot services and runtime services, respectively. However, the naming is confusing, given that the early vs runtime distinction may suggest that these are used for calling the same set of services either early or late (== at runtime), while in reality, the sets of services they can be used with are completely disjoint, and efi_call_runtime is also only usable in 'early' code. So do a global sweep to replace all occurrences with efi_bs_call or efi_rt_call, respectively, where BS and RT match the idiom used by the UEFI spec to refer to boot time or runtime services. While at it, use 'func' as the macro parameter name for the function pointers, which is less likely to collide and cause weird build errors. Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Cc: Arvind Sankar <nivedita@alum.mit.edu> Cc: Borislav Petkov <bp@alien8.de> Cc: James Morse <james.morse@arm.com> Cc: Matt Fleming <matt@codeblueprint.co.uk> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-efi@vger.kernel.org Link: https://lkml.kernel.org/r/20191224151025.32482-24-ardb@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-12-25efi/libstub: Drop 'table' argument from efi_table_attr() macroArd Biesheuvel2-13/+7
None of the definitions of the efi_table_attr() still refer to their 'table' argument so let's get rid of it entirely. Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Cc: Arvind Sankar <nivedita@alum.mit.edu> Cc: Borislav Petkov <bp@alien8.de> Cc: James Morse <james.morse@arm.com> Cc: Matt Fleming <matt@codeblueprint.co.uk> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-efi@vger.kernel.org Link: https://lkml.kernel.org/r/20191224151025.32482-23-ardb@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-12-25efi/libstub: Drop protocol argument from efi_call_proto() macroArd Biesheuvel3-14/+11
After refactoring the mixed mode support code, efi_call_proto() no longer uses its protocol argument in any of its implementation, so let's remove it altogether. Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Cc: Arvind Sankar <nivedita@alum.mit.edu> Cc: Borislav Petkov <bp@alien8.de> Cc: James Morse <james.morse@arm.com> Cc: Matt Fleming <matt@codeblueprint.co.uk> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-efi@vger.kernel.org Link: https://lkml.kernel.org/r/20191224151025.32482-22-ardb@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-12-25efi/libstub/x86: Work around page freeing issue in mixed modeArd Biesheuvel1-1/+4
Mixed mode translates calls from the 64-bit kernel into the 32-bit firmware by wrapping them in a call to a thunking routine that pushes a 32-bit word onto the stack for each argument passed to the function, regardless of the argument type. This works surprisingly well for most services and protocols, with the exception of ones that take explicit 64-bit arguments. efi_free() invokes the FreePages() EFI boot service, which takes a efi_physical_addr_t as its address argument, and this is one of those 64-bit types. This means that the 32-bit firmware will interpret the (addr, size) pair as a single 64-bit quantity, and since it is guaranteed to have the high word set (as size > 0), it will always fail due to the fact that EFI memory allocations are always < 4 GB on 32-bit firmware. So let's fix this by giving the thunking code a little hand, and pass two values for the address, and a third one for the size. Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Cc: Arvind Sankar <nivedita@alum.mit.edu> Cc: Borislav Petkov <bp@alien8.de> Cc: James Morse <james.morse@arm.com> Cc: Matt Fleming <matt@codeblueprint.co.uk> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-efi@vger.kernel.org Link: https://lkml.kernel.org/r/20191224151025.32482-21-ardb@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-12-25efi/libstub: Remove 'sys_table_arg' from all function prototypesArd Biesheuvel10-139/+111
We have a helper efi_system_table() that gives us the address of the EFI system table in memory, so there is no longer point in passing it around from each function to the next. Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Cc: Arvind Sankar <nivedita@alum.mit.edu> Cc: Borislav Petkov <bp@alien8.de> Cc: James Morse <james.morse@arm.com> Cc: Matt Fleming <matt@codeblueprint.co.uk> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-efi@vger.kernel.org Link: https://lkml.kernel.org/r/20191224151025.32482-20-ardb@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-12-25efi/libstub: Drop sys_table_arg from printk routinesArd Biesheuvel8-61/+59
As a first step towards getting rid of the need to pass around a function parameter 'sys_table_arg' pointing to the EFI system table, remove the references to it in the printing code, which is represents the majority of the use cases. Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Cc: Arvind Sankar <nivedita@alum.mit.edu> Cc: Borislav Petkov <bp@alien8.de> Cc: James Morse <james.morse@arm.com> Cc: Matt Fleming <matt@codeblueprint.co.uk> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-efi@vger.kernel.org Link: https://lkml.kernel.org/r/20191224151025.32482-19-ardb@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-12-25efi/libstub: Unify the efi_char16_printk implementationsArd Biesheuvel2-9/+9
Use a single implementation for efi_char16_printk() across all architectures. Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Cc: Arvind Sankar <nivedita@alum.mit.edu> Cc: Borislav Petkov <bp@alien8.de> Cc: James Morse <james.morse@arm.com> Cc: Matt Fleming <matt@codeblueprint.co.uk> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-efi@vger.kernel.org Link: https://lkml.kernel.org/r/20191224151025.32482-17-ardb@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-12-25efi/libstub: Get rid of 'sys_table_arg' macro parameterArd Biesheuvel3-1/+14
The efi_call macros on ARM have a dependency on a variable 'sys_table_arg' existing in the scope of the macro instantiation. Since this variable always points to the same data structure, let's create a global getter for it and use that instead. Note that the use of a global variable with external linkage is avoided, given the problems we had in the past with early processing of the GOT tables. While at it, drop the redundant casts in the efi_table_attr and efi_call_proto macros. Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Cc: Arvind Sankar <nivedita@alum.mit.edu> Cc: Borislav Petkov <bp@alien8.de> Cc: James Morse <james.morse@arm.com> Cc: Matt Fleming <matt@codeblueprint.co.uk> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-efi@vger.kernel.org Link: https://lkml.kernel.org/r/20191224151025.32482-16-ardb@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-12-25efi/libstub: Avoid protocol wrapper for file I/O routinesArd Biesheuvel1-10/+7
The EFI file I/O routines built on top of the file I/O firmware services are incompatible with mixed mode, so there is no need to obfuscate them by using protocol wrappers whose only purpose is to hide the mixed mode handling. So let's switch to plain indirect calls instead. This also means we can drop the mixed_mode aliases from the various types involved. Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Cc: Arvind Sankar <nivedita@alum.mit.edu> Cc: Borislav Petkov <bp@alien8.de> Cc: James Morse <james.morse@arm.com> Cc: Matt Fleming <matt@codeblueprint.co.uk> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-efi@vger.kernel.org Link: https://lkml.kernel.org/r/20191224151025.32482-15-ardb@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-12-25efi/libstub: Annotate firmware routines as __efiapiArd Biesheuvel1-4/+6
Annotate all the firmware routines (boot services, runtime services and protocol methods) called in the boot context as __efiapi, and make it expand to __attribute__((ms_abi)) on 64-bit x86. This allows us to use the compiler to generate the calls into firmware that use the MS calling convention instead of the SysV one. Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Cc: Arvind Sankar <nivedita@alum.mit.edu> Cc: Borislav Petkov <bp@alien8.de> Cc: James Morse <james.morse@arm.com> Cc: Matt Fleming <matt@codeblueprint.co.uk> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-efi@vger.kernel.org Link: https://lkml.kernel.org/r/20191224151025.32482-13-ardb@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-12-25efi/libstub: Use stricter typing for firmware function pointersArd Biesheuvel2-4/+5
We will soon remove another level of pointer casting, so let's make sure all type handling involving firmware calls at boot time is correct. Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Cc: Arvind Sankar <nivedita@alum.mit.edu> Cc: Borislav Petkov <bp@alien8.de> Cc: James Morse <james.morse@arm.com> Cc: Matt Fleming <matt@codeblueprint.co.uk> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-efi@vger.kernel.org Link: https://lkml.kernel.org/r/20191224151025.32482-12-ardb@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-12-25efi/libstub: Drop explicit 32/64-bit protocol definitionsArd Biesheuvel1-10/+0
Now that we have incorporated the mixed mode protocol definitions into the native ones using unions, we no longer need the separate 32/64 bit struct definitions, with the exception of the EFI system table definition and the boot services, runtime services and configuration table definitions. So drop the unused ones. Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Cc: Arvind Sankar <nivedita@alum.mit.edu> Cc: Borislav Petkov <bp@alien8.de> Cc: James Morse <james.morse@arm.com> Cc: Matt Fleming <matt@codeblueprint.co.uk> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-efi@vger.kernel.org Link: https://lkml.kernel.org/r/20191224151025.32482-11-ardb@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-12-25efi/libstub: Distinguish between native/mixed not 32/64 bitArd Biesheuvel1-30/+15
Currently, we support mixed mode by casting all boot time firmware calls to 64-bit explicitly on native 64-bit systems, and to 32-bit on 32-bit systems or 64-bit systems running with 32-bit firmware. Due to this explicit awareness of the bitness in the code, we do a lot of casting even on generic code that is shared with other architectures, where mixed mode does not even exist. This casting leads to loss of coverage of type checking by the compiler, which we should try to avoid. So instead of distinguishing between 32-bit vs 64-bit, distinguish between native vs mixed, and limit all the nasty casting and pointer mangling to the code that actually deals with mixed mode. Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Cc: Arvind Sankar <nivedita@alum.mit.edu> Cc: Borislav Petkov <bp@alien8.de> Cc: James Morse <james.morse@arm.com> Cc: Matt Fleming <matt@codeblueprint.co.uk> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-efi@vger.kernel.org Link: https://lkml.kernel.org/r/20191224151025.32482-10-ardb@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-12-25efi/libstub: Extend native protocol definitions with mixed_mode aliasesArd Biesheuvel2-10/+16
In preparation of moving to a native vs. mixed mode split rather than a 32 vs. 64 bit split when it comes to invoking EFI firmware services, update all the native protocol definitions and redefine them as unions containing an anonymous struct for the native view and a struct called 'mixed_mode' describing the 32-bit view of the protocol when called from 64-bit code. While at it, flesh out some PCI I/O member definitions that we will be needing shortly. Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Cc: Arvind Sankar <nivedita@alum.mit.edu> Cc: Borislav Petkov <bp@alien8.de> Cc: James Morse <james.morse@arm.com> Cc: Matt Fleming <matt@codeblueprint.co.uk> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-efi@vger.kernel.org Link: https://lkml.kernel.org/r/20191224151025.32482-9-ardb@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-12-25efi/libstub: Use a helper to iterate over a EFI handle arrayArd Biesheuvel1-7/+2
Iterating over a EFI handle array is a bit finicky, since we have to take mixed mode into account, where handles are only 32-bit while the native efi_handle_t type is 64-bit. So introduce a helper, and replace the various occurrences of this pattern. Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Cc: Arvind Sankar <nivedita@alum.mit.edu> Cc: Borislav Petkov <bp@alien8.de> Cc: James Morse <james.morse@arm.com> Cc: Matt Fleming <matt@codeblueprint.co.uk> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-efi@vger.kernel.org Link: https://lkml.kernel.org/r/20191224151025.32482-8-ardb@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-12-25efi/gop: Unify 32/64-bit functionsArvind Sankar1-116/+18
Use efi_table_attr macro to deal with 32/64-bit firmware using the same source code. Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu> Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: James Morse <james.morse@arm.com> Cc: Matt Fleming <matt@codeblueprint.co.uk> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-efi@vger.kernel.org Link: https://lkml.kernel.org/r/20191224151025.32482-5-ardb@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-12-25efi/gop: Convert GOP structures to typedef and clean up some typesArvind Sankar1-13/+13
Use typedef for the GOP structures, in anticipation of unifying 32/64-bit code. Also use more appropriate types in the non-bitness specific structures for the framebuffer address and pointers. Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu> Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: James Morse <james.morse@arm.com> Cc: Matt Fleming <matt@codeblueprint.co.uk> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-efi@vger.kernel.org Link: https://lkml.kernel.org/r/20191224151025.32482-4-ardb@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-12-25efi/libstub/random: Initialize pointer variables to zero for mixed modeHans de Goede1-3/+3
Commit: 0d95981438c3 ("x86: efi/random: Invoke EFI_RNG_PROTOCOL to seed the UEFI RNG table") causes the drivers/efi/libstub/random.c code to get used on x86 for the first time. But this code was not written with EFI mixed mode in mind (running a 64 bit kernel on 32 bit EFI firmware), this causes the kernel to crash during early boot when running in mixed mode. The problem is that in mixed mode pointers are 64 bit, but when running on a 32 bit firmware, EFI calls which return a pointer value by reference only fill the lower 32 bits of the passed pointer, leaving the upper 32 bits uninitialized which leads to crashes. This commit fixes this by initializing pointers which are passed by reference to EFI calls to NULL before passing them, so that the upper 32 bits are initialized to 0. Signed-off-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Cc: Arvind Sankar <nivedita@alum.mit.edu> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-efi@vger.kernel.org Fixes: 0d95981438c3 ("x86: efi/random: Invoke EFI_RNG_PROTOCOL to seed the UEFI RNG table") Link: https://lkml.kernel.org/r/20191224132909.102540-3-ardb@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-12-25efi/earlycon: Fix write-combine mapping on x86Arvind Sankar1-9/+7
On x86, until PAT is initialized, WC translates into UC-. Since we calculate and store pgprot_writecombine(PAGE_KERNEL) when earlycon is initialized, this means we actually use UC- mappings instead of WC mappings, which makes scrolling very slow. Instead store a boolean flag to indicate whether we want to use writeback or write-combine mappings, and recalculate the actual pgprot_t we need on every mapping. Once PAT is initialized, we will start using write-combine mappings, which speeds up the scrolling considerably. Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu> Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Cc: Hans de Goede <hdegoede@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-efi@vger.kernel.org Fixes: 69c1f396f25b ("efi/x86: Convert x86 EFI earlyprintk into generic earlycon implementation") Link: https://lkml.kernel.org/r/20191224132909.102540-2-ardb@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-12-17Merge branch 'efi-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds4-63/+88
Pull EFI fixes from Ingo Molnar: "Protect presistent EFI memory reservations from kexec, fix EFIFB early console, EFI stub graphics output fixes and other misc fixes." * 'efi-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: efi: Don't attempt to map RCI2 config table if it doesn't exist efi/earlycon: Remap entire framebuffer after page initialization efi: Fix efi_loaded_image_t::unload type efi/gop: Fix memory leak in __gop_query32/64() efi/gop: Return EFI_SUCCESS if a usable GOP was found efi/gop: Return EFI_NOT_FOUND if there are no usable GOPs efi/memreserve: Register reservations as 'reserved' in /proc/iomem
2019-12-10efi: Don't attempt to map RCI2 config table if it doesn't existArd Biesheuvel1-0/+3
Commit: 1c5fecb61255aa12 ("efi: Export Runtime Configuration Interface table to sysfs") ... added support for a Dell specific UEFI configuration table, but failed to take into account that mapping the table should not be attempted unless the table actually exists. If it doesn't exist, the code usually fails silently unless pr_debug() prints are enabled. However, on 32-bit PAE x86, the splat below is produced due to the attempt to map the placeholder value EFI_INVALID_TABLE_ADDR which we use for non-existing UEFI configuration tables, and which equals ULONG_MAX. memremap attempted on mixed range 0x00000000ffffffff size: 0x1e WARNING: CPU: 1 PID: 1 at kernel/iomem.c:81 memremap+0x1a3/0x1c0 Modules linked in: CPU: 1 PID: 1 Comm: swapper/0 Not tainted 5.4.2-smp-mine #1 Hardware name: Hewlett-Packard HP Z400 Workstation/0B4Ch, BIOS 786G3 v03.61 03/05/2018 EIP: memremap+0x1a3/0x1c0 ... Call Trace: ? map_properties+0x473/0x473 ? efi_rci2_sysfs_init+0x2c/0x154 ? map_properties+0x473/0x473 ? do_one_initcall+0x49/0x1d4 ? parse_args+0x1e8/0x2a0 ? do_early_param+0x7a/0x7a ? kernel_init_freeable+0x139/0x1c2 ? rest_init+0x8e/0x8e ? kernel_init+0xd/0xf2 ? ret_from_fork+0x2e/0x38 Fix this by checking whether the table exists before attempting to map it. Reported-by: Richard Narron <comet.berkeley@gmail.com> Tested-by: Richard Narron <comet.berkeley@gmail.com> Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Cc: linux-efi@vger.kernel.org Fixes: 1c5fecb61255aa12 ("efi: Export Runtime Configuration Interface table to sysfs") Link: https://lkml.kernel.org/r/20191210090945.11501-2-ardb@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-12-10efi/capsule-loader: Explicitly include linux/io.h for page_to_phys()Sean Christopherson1-0/+1
Through a labyrinthian sequence of includes, usage of page_to_phys() is dependent on the include of asm/io.h in x86's asm/realmode.h, which is included in x86's asm/acpi.h and thus by linux/acpi.h. Explicitly include linux/io.h to break the dependency on realmode.h so that a future patch can remove the realmode.h include from acpi.h without breaking the build. Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com> Link: https://lkml.kernel.org/r/20191126165417.22423-7-sean.j.christopherson@intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-12-09treewide: Use sizeof_field() macroPankaj Bharadiya1-1/+1
Replace all the occurrences of FIELD_SIZEOF() with sizeof_field() except at places where these are defined. Later patches will remove the unused definition of FIELD_SIZEOF(). This patch is generated using following script: EXCLUDE_FILES="include/linux/stddef.h|include/linux/kernel.h" git grep -l -e "\bFIELD_SIZEOF\b" | while read file; do if [[ "$file" =~ $EXCLUDE_FILES ]]; then continue fi sed -i -e 's/\bFIELD_SIZEOF\b/sizeof_field/g' $file; done Signed-off-by: Pankaj Bharadiya <pankaj.laxminarayan.bharadiya@intel.com> Link: https://lore.kernel.org/r/20190924105839.110713-3-pankaj.laxminarayan.bharadiya@intel.com Co-developed-by: Kees Cook <keescook@chromium.org> Signed-off-by: Kees Cook <keescook@chromium.org> Acked-by: David Miller <davem@davemloft.net> # for net
2019-12-08efi/earlycon: Remap entire framebuffer after page initializationAndy Shevchenko1-0/+40
When commit: 69c1f396f25b ("efi/x86: Convert x86 EFI earlyprintk into generic earlycon implementation") moved the x86 specific EFI earlyprintk implementation to a shared location, it also tweaked the behaviour. In particular, it dropped a trick with full framebuffer remapping after page initialization, leading to two regressions: 1) very slow scrolling after page initialization, 2) kernel hang when the 'keep_bootcon' command line argument is passed. Putting the tweak back fixes #2 and mitigates #1, i.e., it limits the slow behavior to the early boot stages, presumably due to eliminating heavy map()/unmap() operations per each pixel line on the screen. [ ardb: ensure efifb is unmapped again unless keep_bootcon is in effect. ] [ mingo: speling fixes. ] Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Cc: Arvind Sankar <nivedita@alum.mit.edu> Cc: Bhupesh Sharma <bhsharma@redhat.com> Cc: Masayoshi Mizuma <m.mizuma@jp.fujitsu.com> Cc: linux-efi@vger.kernel.org Fixes: 69c1f396f25b ("efi/x86: Convert x86 EFI earlyprintk into generic earlycon implementation") Link: https://lkml.kernel.org/r/20191206165542.31469-7-ardb@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-12-08efi/gop: Fix memory leak in __gop_query32/64()Arvind Sankar1-54/+12
efi_graphics_output_protocol::query_mode() returns info in callee-allocated memory which must be freed by the caller, which we aren't doing. We don't actually need to call query_mode() in order to obtain the info for the current graphics mode, which is already there in gop->mode->info, so just access it directly in the setup_gop32/64() functions. Also nothing uses the size of the info structure, so don't update the passed-in size (which is the size of the gop_handle table in bytes) unnecessarily. Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu> Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Bhupesh Sharma <bhsharma@redhat.com> Cc: Masayoshi Mizuma <m.mizuma@jp.fujitsu.com> Cc: linux-efi@vger.kernel.org Link: https://lkml.kernel.org/r/20191206165542.31469-5-ardb@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-12-08efi/gop: Return EFI_SUCCESS if a usable GOP was foundArvind Sankar1-2/+2
If we've found a usable instance of the Graphics Output Protocol (GOP) with a framebuffer, it is possible that one of the later EFI calls fails while checking if any support console output. In this case status may be an EFI error code even though we found a usable GOP. Fix this by explicitly return EFI_SUCCESS if a usable GOP has been located. Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu> Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Bhupesh Sharma <bhsharma@redhat.com> Cc: Masayoshi Mizuma <m.mizuma@jp.fujitsu.com> Cc: linux-efi@vger.kernel.org Link: https://lkml.kernel.org/r/20191206165542.31469-4-ardb@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-12-08efi/gop: Return EFI_NOT_FOUND if there are no usable GOPsArvind Sankar1-6/+6
If we don't find a usable instance of the Graphics Output Protocol (GOP) because none of them have a framebuffer (i.e. they were all PIXEL_BLT_ONLY), but all the EFI calls succeeded, we will return EFI_SUCCESS even though we didn't find a usable GOP. Fix this by explicitly returning EFI_NOT_FOUND if no usable GOPs are found, allowing the caller to probe for UGA instead. Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu> Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Bhupesh Sharma <bhsharma@redhat.com> Cc: Masayoshi Mizuma <m.mizuma@jp.fujitsu.com> Cc: linux-efi@vger.kernel.org Link: https://lkml.kernel.org/r/20191206165542.31469-3-ardb@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-12-08efi/memreserve: Register reservations as 'reserved' in /proc/iomemArd Biesheuvel1-2/+26
Memory regions that are reserved using efi_mem_reserve_persistent() are recorded in a special EFI config table which survives kexec, allowing the incoming kernel to honour them as well. However, such reservations are not visible in /proc/iomem, and so the kexec tools that load the incoming kernel and its initrd into memory may overwrite these reserved regions before the incoming kernel has a chance to reserve them from further use. Address this problem by adding these reservations to /proc/iomem as they are created. Note that reservations that are inherited from a previous kernel are memblock_reserve()'d early on, so they are already visible in /proc/iomem. Tested-by: Masayoshi Mizuma <m.mizuma@jp.fujitsu.com> Tested-by: Bhupesh Sharma <bhsharma@redhat.com> Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Reviewed-by: Bhupesh Sharma <bhsharma@redhat.com> Cc: <stable@vger.kernel.org> # v5.4+ Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Arvind Sankar <nivedita@alum.mit.edu> Cc: linux-efi@vger.kernel.org Link: https://lkml.kernel.org/r/20191206165542.31469-2-ardb@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
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