[tip: x86/urgent] x86/boot: Move EFI range reservation after cmdline parsing - tip-bot2 for Mike Rapoport

From: "tip-bot2 for Mike Rapoport" <tip-bot2@linutronix.de>
To: linux-tip-commits@vger.kernel.org
Cc: Borislav Petkov <bp@suse.de>, Mike Rapoport <rppt@kernel.org>,
	x86@kernel.org, linux-kernel@vger.kernel.org
Subject: [tip: x86/urgent] x86/boot: Move EFI range reservation after cmdline parsing
Date: Wed, 15 Dec 2021 13:05:46 -0000	[thread overview]
Message-ID: <163957354693.23020.8537268805198191781.tip-bot2@tip-bot2> (raw)
In-Reply-To: <e8dd8993c38702ee6dd73b3c11f158617e665607.camel@intel.com>

The following commit has been merged into the x86/urgent branch of tip:

Commit-ID:     83757bbb9fe029b704fb28e80c3f2b92f23a1994
Gitweb:        https://git.kernel.org/tip/83757bbb9fe029b704fb28e80c3f2b92f23a1994
Author:        Mike Rapoport <rppt@kernel.org>
AuthorDate:    Mon, 13 Dec 2021 12:27:57 +01:00
Committer:     Borislav Petkov <bp@suse.de>
CommitterDate: Wed, 15 Dec 2021 12:36:47 +01:00

x86/boot: Move EFI range reservation after cmdline parsing

The memory reservation in arch/x86/platform/efi/efi.c depends on at
least two command line parameters. Put it back later in the boot process
and move efi_memblock_x86_reserve_range() out of early_memory_reserve().

An attempt to fix this was done in

  8d48bf8206f7 ("x86/boot: Pull up cmdline preparation and early param parsing")

but that caused other troubles so it got reverted.

The bug this is addressing is:

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.

 [ bp: Produce into a proper patch. ]

Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Mike Rapoport <rppt@kernel.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lore.kernel.org/r/e8dd8993c38702ee6dd73b3c11f158617e665607.camel@intel.com
Link: https://lore.kernel.org/r/20211213112757.2612-4-bp@alien8.de
---
 arch/x86/kernel/setup.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c
index 49b596d..e04f5e6 100644
--- a/arch/x86/kernel/setup.c
+++ b/arch/x86/kernel/setup.c
@@ -713,9 +713,6 @@ static void __init early_reserve_memory(void)
 
 	early_reserve_initrd();
 
-	if (efi_enabled(EFI_BOOT))
-		efi_memblock_x86_reserve_range();
-
 	memblock_x86_reserve_range_setup_data();
 
 	reserve_ibft_region();
@@ -890,6 +887,9 @@ void __init setup_arch(char **cmdline_p)
 
 	parse_early_param();
 
+	if (efi_enabled(EFI_BOOT))
+		efi_memblock_x86_reserve_range();
+
 #ifdef CONFIG_MEMORY_HOTPLUG
 	/*
 	 * Memory used by the kernel cannot be hot-removed because Linux
