On 06.03.2026 14:29, Soumyajyotii Ssarkar wrote:
> As described in the task, BGRT preservation is now enabled by default to fix
> ACPI corruption
> for desktop/workstation systems (similar to ESRT).
What's "the task"?
> Add an opt-out parameter 'efi=no-bgrt' to allow disabling BGRT
> preservation on systems where the ~1MB memory overhead is not
> desired.
This looks to contradict ...
> The parameter is parsed during normal Xen boot (not during EFI
> phase), so it only affects diagnostic logging.
... this. For xen.efi you want to add code to the command line parsing
near the top of efi_start(). What to do for the MB2 boot path perhaps
the only thing there is to peek into the command line (see
arch/x86/boot/cmdline.c).
> @@ -1873,6 +1877,10 @@ static int __init cf_check parse_efi_param(const char
> *s)
> else
> __clear_bit(EFI_RS, &efi_flags);
> }
> + else if ( (ss - s) == 7 && !memcmp(s, "no-bgrt", 7) )
No "no-" prefixes please; you want to use parse_boolean().
> @@ -1968,7 +1976,11 @@ void __init efi_init_memory(void)
> if ( !efi_enabled(EFI_BOOT) )
> return;
>
> - if ( bgrt_debug_info.preserved )
> + if ( opt_bgrt_disabled )
> + {
> + printk(XENLOG_INFO "EFI: BGRT preservation disabled\n");
> + }
No need for figure braces here.
Jan
