kernel/drivers/firmware/efi/memmap.c, branch linux-6.5.y

efi: xen: Set EFI_PARAVIRT for Xen dom0 boot on all architectures

2022-11-18T08:14:09Z

Currently, the EFI_PARAVIRT flag is only used by Xen dom0 boot on x86, even though other architectures also support pseudo-EFI boot, where the core kernel is invoked directly and provided with a set of data tables that resemble the ones constructed by the EFI stub, which never actually runs in that case. Let's fix this inconsistency, and always set this flag when booting dom0 via the EFI boot path. Note that Xen on x86 does not provide the EFI memory map in this case, whereas other architectures do, so move the associated EFI_PARAVIRT check into the x86 platform code. Signed-off-by: Ard Biesheuvel

efi: memmap: Move manipulation routines into x86 arch tree

2022-11-18T08:14:09Z

The EFI memory map is a description of the memory layout as provided by the firmware, and only x86 manipulates it in various different ways for its own memory bookkeeping. So let's move the memmap routines that are only used by x86 into the x86 arch tree. Signed-off-by: Ard Biesheuvel

drivers: fix typo in firmware/efi/memmap.c

2022-06-28T18:00:11Z

This patch fixes the spelling error in firmware/efi/memmap.c, changing it to the correct word. Signed-off-by: Zheng Zhi Yuan Signed-off-by: Ard Biesheuvel

efi: Correct comment on efi_memmap_alloc

2022-06-15T15:48:58Z

Returning zero means success now. Signed-off-by: Liu Zixian Signed-off-by: Ard Biesheuvel

memblock: rename memblock_free to memblock_phys_free

2021-11-06T20:30:41Z

Since memblock_free() operates on a physical range, make its name reflect it and rename it to memblock_phys_free(), so it will be a logical counterpart to memblock_phys_alloc(). The callers are updated with the below semantic patch: @@ expression addr; expression size; @@ - memblock_free(addr, size); + memblock_phys_free(addr, size); Link: https://lkml.kernel.org/r/20210930185031.18648-6-rppt@kernel.org Signed-off-by: Mike Rapoport Cc: Christophe Leroy Cc: Juergen Gross Cc: Shahab Vahedi Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

efi: Fix handling of multiple efi_fake_mem= entries

2020-01-20T07:14:29Z

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 Signed-off-by: Dan Williams Signed-off-by: Ard Biesheuvel Signed-off-by: Ingo Molnar 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

efi: Fix efi_memmap_alloc() leaks

2020-01-20T07:14:29Z

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 Signed-off-by: Ard Biesheuvel Signed-off-by: Ingo Molnar Link: https://lore.kernel.org/r/20200113172245.27925-13-ardb@kernel.org

efi: Add tracking for dynamically allocated memmaps

2020-01-20T07:14:29Z

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 Signed-off-by: Ard Biesheuvel Signed-off-by: Ingo Molnar Link: https://lore.kernel.org/r/20200113172245.27925-12-ardb@kernel.org

efi: Add a flags parameter to efi_memory_map

2020-01-20T07:14:28Z

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 Signed-off-by: Ard Biesheuvel Signed-off-by: Ingo Molnar Link: https://lore.kernel.org/r/20200113172245.27925-11-ardb@kernel.org

efi/arm: Revert deferred unmap of early memmap mapping

2018-11-15T09:04:46Z

Commit: 3ea86495aef2 ("efi/arm: preserve early mapping of UEFI memory map longer for BGRT") deferred the unmap of the early mapping of the UEFI memory map to accommodate the ACPI BGRT code, which looks up the memory type that backs the BGRT table to validate it against the requirements of the UEFI spec. Unfortunately, this causes problems on ARM, which does not permit early mappings to persist after paging_init() is called, resulting in a WARN() splat. Since we don't support the BGRT table on ARM anway, let's revert ARM to the old behaviour, which is to take down the early mapping at the end of efi_init(). Signed-off-by: Ard Biesheuvel Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: linux-efi@vger.kernel.org Fixes: 3ea86495aef2 ("efi/arm: preserve early mapping of UEFI memory ...") Link: http://lkml.kernel.org/r/20181114175544.12860-3-ard.biesheuvel@linaro.org Signed-off-by: Ingo Molnar