Commit 8d48bf82 authored by Borislav Petkov's avatar Borislav Petkov
Browse files

x86/boot: Pull up cmdline preparation and early param parsing 



Dan reports that Anjaneya Chagam can no longer use the efi=nosoftreserve
kernel command line parameter to suppress "soft reservation" behavior.

This is due to the fact that the following call-chain happens at boot:

early_reserve_memory
|-> efi_memblock_x86_reserve_range
    |-> efi_fake_memmap_early

which does

        if (!efi_soft_reserve_enabled())
                return;

and that would have set EFI_MEM_NO_SOFT_RESERVE after having parsed
"nosoftreserve".

However, parse_early_param() gets called *after* it, leading to the boot
cmdline not being taken into account.

Therefore, carve out the command line preparation into a separate
function which does the early param parsing too. So that it all goes
together.

And then call that function before early_reserve_memory() so that the
params would have been parsed by then.

Fixes: 8aa83e63 ("x86/setup: Call early_reserve_memory() earlier")
Reported-by: default avatarDan Williams <dan.j.williams@intel.com>
Reviewed-by: default avatarDan Williams <dan.j.williams@intel.com>
Signed-off-by: default avatarBorislav Petkov <bp@suse.de>
Tested-by: default avatarAnjaneya Chagam <anjaneya.chagam@intel.com>
Cc: <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/e8dd8993c38702ee6dd73b3c11f158617e665607.camel@intel.com
parent fa55b7dc

arch/x86/kernel/setup.c

+39 −27
Original line number Diff line number Diff line
@@ -742,6 +742,28 @@ dump_kernel_offset(struct notifier_block *self, unsigned long v, void *p) 
	return 0;

}



static char *prepare_command_line(void)

{

#ifdef CONFIG_CMDLINE_BOOL

#ifdef CONFIG_CMDLINE_OVERRIDE

	strlcpy(boot_command_line, builtin_cmdline, COMMAND_LINE_SIZE);

#else

	if (builtin_cmdline[0]) {

		/* append boot loader cmdline to builtin */

		strlcat(builtin_cmdline, " ", COMMAND_LINE_SIZE);

		strlcat(builtin_cmdline, boot_command_line, COMMAND_LINE_SIZE);

		strlcpy(boot_command_line, builtin_cmdline, COMMAND_LINE_SIZE);

	}

#endif

#endif



	strlcpy(command_line, boot_command_line, COMMAND_LINE_SIZE);



	parse_early_param();



	return command_line;

}



/*

 * Determine if we were loaded by an EFI loader.  If so, then we have also been

 * passed the efi memmap, systab, etc., so we should use these data structures
@@ -830,6 +852,23 @@ void __init setup_arch(char **cmdline_p) 


	x86_init.oem.arch_setup();



	/*

	 * x86_configure_nx() is called before parse_early_param() (called by

	 * prepare_command_line()) to detect whether hardware doesn't support

	 * NX (so that the early EHCI debug console setup can safely call

	 * set_fixmap()). It may then be called again from within noexec_setup()

	 * during parsing early parameters to honor the respective command line

	 * option.

	 */

	x86_configure_nx();



	/*

	 * This parses early params and it needs to run before

	 * early_reserve_memory() because latter relies on such settings

	 * supplied as early params.

	 */

	*cmdline_p = prepare_command_line();



	/*

	 * Do some memory reservations *before* memory is added to memblock, so

	 * memblock allocations won't overwrite it.
@@ -863,33 +902,6 @@ void __init setup_arch(char **cmdline_p) 
	bss_resource.start = __pa_symbol(__bss_start);

	bss_resource.end = __pa_symbol(__bss_stop)-1;



#ifdef CONFIG_CMDLINE_BOOL

#ifdef CONFIG_CMDLINE_OVERRIDE

	strlcpy(boot_command_line, builtin_cmdline, COMMAND_LINE_SIZE);

#else

	if (builtin_cmdline[0]) {

		/* append boot loader cmdline to builtin */

		strlcat(builtin_cmdline, " ", COMMAND_LINE_SIZE);

		strlcat(builtin_cmdline, boot_command_line, COMMAND_LINE_SIZE);

		strlcpy(boot_command_line, builtin_cmdline, COMMAND_LINE_SIZE);

	}

#endif

#endif



	strlcpy(command_line, boot_command_line, COMMAND_LINE_SIZE);

	*cmdline_p = command_line;



	/*

	 * x86_configure_nx() is called before parse_early_param() to detect

	 * whether hardware doesn't support NX (so that the early EHCI debug

	 * console setup can safely call set_fixmap()). It may then be called

	 * again from within noexec_setup() during parsing early parameters

	 * to honor the respective command line option.

	 */

	x86_configure_nx();



	parse_early_param();



#ifdef CONFIG_MEMORY_HOTPLUG

	/*

	 * Memory used by the kernel cannot be hot-removed because Linux