linux_dsm_epyc7002/drivers/firmware/efi
Ard Biesheuvel 2a55280a36 efi/libstub: arm: Print CPU boot mode and MMU state at boot
On 32-bit ARM, we may boot at HYP mode, or with the MMU and caches off
(or both), even though the EFI spec does not actually support this.
While booting at HYP mode is something we might tolerate, fiddling
with the caches is a more serious issue, as disabling the caches is
tricky to do safely from C code, and running without the Dcache makes
it impossible to support unaligned memory accesses, which is another
explicit requirement imposed by the EFI spec.

So take note of the CPU mode and MMU state in the EFI stub diagnostic
output so that we can easily diagnose any issues that may arise from
this. E.g.,

  EFI stub: Entering in SVC mode with MMU enabled

Also, capture the CPSR and SCTLR system register values at EFI stub
entry, and after ExitBootServices() returns, and check whether the
MMU and Dcache were disabled at any point. If this is the case, a
diagnostic message like the following will be emitted:

  efi: [Firmware Bug]: EFI stub was entered with MMU and Dcache disabled, please fix your firmware!
  efi: CPSR at EFI stub entry        : 0x600001d3
  efi: SCTLR at EFI stub entry       : 0x00c51838
  efi: CPSR after ExitBootServices() : 0x600001d3
  efi: SCTLR after ExitBootServices(): 0x00c50838

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Reviewed-by: Leif Lindholm <leif@nuviainc.com>
2020-06-17 15:29:11 +02:00
..
libstub efi/libstub: arm: Print CPU boot mode and MMU state at boot 2020-06-17 15:29:11 +02:00
test efi_test: get rid of pointless access_ok() 2020-05-29 11:05:54 -04:00
apple-properties.c efi/dev-path-parser: Add struct definition for vendor type device path nodes 2020-02-23 21:59:42 +01:00
arm-init.c efi/libstub: arm: Print CPU boot mode and MMU state at boot 2020-06-17 15:29:11 +02:00
arm-runtime.c mm: reorder includes after introduction of linux/pgtable.h 2020-06-09 09:39:13 -07:00
capsule-loader.c efi/capsule-loader: Drop superfluous assignment 2020-02-23 21:58:31 +01:00
capsule.c efi: Replace GPL license boilerplate with SPDX headers 2019-02-04 08:27:25 +01:00
cper-arm.c efi: Replace GPL license boilerplate with SPDX headers 2019-02-04 08:27:25 +01:00
cper-x86.c efi: Decode IA32/X64 Context Info structure 2018-05-14 08:57:48 +02:00
cper.c efi: cper: Add support for printing Firmware Error Record Reference 2020-05-14 11:11:20 +02:00
dev-path-parser.c efi/dev-path-parser: Add struct definition for vendor type device path nodes 2020-02-23 21:59:42 +01:00
earlycon.c efi/earlycon: Fix early printk for wider fonts 2020-05-12 12:29:45 +02:00
efi-bgrt.c efi/bgrt: Accept BGRT tables with a version of 0 2020-02-22 23:37:37 +01:00
efi-pstore.c efi: Fix a mistype in comments mentioning efivar_entry_iter_begin() 2020-03-08 10:00:07 +01:00
efi.c efi: Make it possible to disable efivar_ssdt entirely 2020-06-16 11:01:07 +02:00
efibc.c efibc: Replace variable set function in notifier call 2019-06-22 10:24:57 +02:00
efivars.c efi/efivars: Add missing kobject_put() in sysfs entry creation error path 2020-05-22 18:19:06 +02:00
embedded-firmware.c platform/x86: touchscreen_dmi: Add EFI embedded firmware info support 2020-03-20 14:57:54 +01:00
esrt.c efi/esrt: Fix reference count leak in esre_create_sysfs_entry. 2020-06-15 14:38:56 +02:00
fake_mem.c efi: Fix handling of multiple efi_fake_mem= entries 2020-01-20 08:14:29 +01:00
fake_mem.h x86/efi: Add efi_fake_mem support for EFI_MEMORY_SP 2019-11-07 15:44:23 +01:00
fdtparams.c efi/arm: Rewrite FDT param discovery routines 2020-02-23 21:59:42 +01:00
Kconfig efi: Make it possible to disable efivar_ssdt entirely 2020-06-16 11:01:07 +02:00
Makefile efi/libstub: Avoid linking libstub/lib-ksyms.o into vmlinux 2020-03-08 10:00:06 +01:00
memattr.c efi: Move mem_attr_table out of struct efi 2020-02-23 21:59:42 +01:00
memmap.c efi: Fix handling of multiple efi_fake_mem= entries 2020-01-20 08:14:29 +01:00
rci2-table.c efi: Don't attempt to map RCI2 config table if it doesn't exist 2019-12-10 12:13:02 +01:00
reboot.c efi: Use EFI ResetSystem only when available 2020-02-23 21:59:42 +01:00
runtime-map.c efi: Replace GPL license boilerplate with SPDX headers 2019-02-04 08:27:25 +01:00
runtime-wrappers.c efi: Add 'runtime' pointer to struct efi 2020-02-23 21:59:42 +01:00
tpm.c EFI fixes for v5.7-rc6: 2020-05-22 20:06:25 +02:00
vars.c efi: Fix a mistype in comments mentioning efivar_entry_iter_begin() 2020-03-08 10:00:07 +01:00
x86_fake_mem.c x86/efi: Add efi_fake_mem support for EFI_MEMORY_SP 2019-11-07 15:44:23 +01:00