linux_dsm_epyc7002/arch/x86/platform/efi
Peter Jones 0100a3e67a efi/x86: Prune invalid memory map entries and fix boot regression
Some machines, such as the Lenovo ThinkPad W541 with firmware GNET80WW
(2.28), include memory map entries with phys_addr=0x0 and num_pages=0.

These machines fail to boot after the following commit,

  commit 8e80632fb2 ("efi/esrt: Use efi_mem_reserve() and avoid a kmalloc()")

Fix this by removing such bogus entries from the memory map.

Furthermore, currently the log output for this case (with efi=debug)
looks like:

 [    0.000000] efi: mem45: [Reserved           |   |  |  |  |  |  |  |  |  |  |  |  ] range=[0x0000000000000000-0xffffffffffffffff] (0MB)

This is clearly wrong, and also not as informative as it could be.  This
patch changes it so that if we find obviously invalid memory map
entries, we print an error and skip those entries.  It also detects the
display of the address range calculation overflow, so the new output is:

 [    0.000000] efi: [Firmware Bug]: Invalid EFI memory map entries:
 [    0.000000] efi: mem45: [Reserved           |   |  |  |  |  |  |  |   |  |  |  |  ] range=[0x0000000000000000-0x0000000000000000] (invalid)

It also detects memory map sizes that would overflow the physical
address, for example phys_addr=0xfffffffffffff000 and
num_pages=0x0200000000000001, and prints:

 [    0.000000] efi: [Firmware Bug]: Invalid EFI memory map entries:
 [    0.000000] efi: mem45: [Reserved           |   |  |  |  |  |  |  |   |  |  |  |  ] range=[phys_addr=0xfffffffffffff000-0x20ffffffffffffffff] (invalid)

It then removes these entries from the memory map.

Signed-off-by: Peter Jones <pjones@redhat.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
[ardb: refactor for clarity with no functional changes, avoid PAGE_SHIFT]
Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk>
[Matt: Include bugzilla info in commit log]
Cc: <stable@vger.kernel.org> # v4.9+
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: https://bugzilla.kernel.org/show_bug.cgi?id=191121
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-01-14 16:48:53 +01:00
..
early_printk.c treewide: replace obsolete _refok by __ref 2016-08-02 17:31:41 -04:00
efi_32.c x86/mm: Remove kernel_unmap_pages_in_pgd() and efi_cleanup_page_tables() 2016-07-15 10:26:26 +02:00
efi_64.c x86/efi: Prevent mixed mode boot corruption with CONFIG_VMAP_STACK=y 2016-11-13 08:26:40 +01:00
efi_stub_32.S x86/efi: Mark initialization code as such 2014-10-03 18:41:03 +01:00
efi_stub_64.S x86/efi: Fix 7-parameter efi_call()s 2016-05-17 08:25:06 +02:00
efi_thunk_64.S x86/efi: Avoid triple faults during EFI mixed mode calls 2015-02-13 15:42:56 +00:00
efi-bgrt.c x86/efi-bgrt: Use efi_mem_reserve() to avoid copying image data 2016-09-09 16:08:38 +01:00
efi.c efi/x86: Prune invalid memory map entries and fix boot regression 2017-01-14 16:48:53 +01:00
Makefile objtool: Mark non-standard object files and directories 2016-02-29 08:35:02 +01:00
quirks.c x86/efi: Don't allocate memmap through memblock after mm_init() 2017-01-07 08:58:07 +01:00