linux-kernel - [tip: x86/boot] x86/boot: Move setting of memblock parameters to e820__memblock

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <174015175614.10177.6726520992334916379.tip-bot2@tip-bot2>
Date: Fri, 21 Feb 2025 15:29:16 -0000
From: "tip-bot2 for Mike Rapoport (Microsoft)" <tip-bot2@...utronix.de>
To: linux-tip-commits@...r.kernel.org
Cc: "Mike Rapoport (Microsoft)" <rppt@...nel.org>,
 Ingo Molnar <mingo@...nel.org>, x86@...nel.org, linux-kernel@...r.kernel.org
Subject: [tip: x86/boot] x86/boot: Move setting of memblock parameters to
 e820__memblock_setup()

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

Commit-ID:     2d6bff31399b2443aba230cd20f120acb2d4eeb1
Gitweb:        https://git.kernel.org/tip/2d6bff31399b2443aba230cd20f120acb2d4eeb1
Author:        Mike Rapoport (Microsoft) <rppt@...nel.org>
AuthorDate:    Fri, 14 Feb 2025 11:06:48 +02:00
Committer:     Ingo Molnar <mingo@...nel.org>
CommitterDate: Fri, 21 Feb 2025 16:05:00 +01:00

x86/boot: Move setting of memblock parameters to e820__memblock_setup()

Changing memblock parameters, namely bottom_up and allocation upper
limit does not have any effect before memblock initialization in
e820__memblock_setup().

Move the calls to memblock_set_bottom_up() and memblock_set_current_limit()
to e820__memblock_setup() to group all the memblock initial setup and make
setup_arch() more readable.

No functional changes.

Signed-off-by: Mike Rapoport (Microsoft) <rppt@...nel.org>
Signed-off-by: Ingo Molnar <mingo@...nel.org>
Link: https://lore.kernel.org/r/20250214090651.3331663-2-rppt@kernel.org
---
 arch/x86/kernel/e820.c  | 30 ++++++++++++++++++++++++++++++
 arch/x86/kernel/setup.c | 25 -------------------------
 2 files changed, 30 insertions(+), 25 deletions(-)

diff --git a/arch/x86/kernel/e820.c b/arch/x86/kernel/e820.c
index 82b96ed..8d8bd03 100644
--- a/arch/x86/kernel/e820.c
+++ b/arch/x86/kernel/e820.c
@@ -1302,6 +1302,36 @@ void __init e820__memblock_setup(void)
 	int i;
 	u64 end;
 
+#ifdef CONFIG_MEMORY_HOTPLUG
+	/*
+	 * Memory used by the kernel cannot be hot-removed because Linux
+	 * cannot migrate the kernel pages. When memory hotplug is
+	 * enabled, we should prevent memblock from allocating memory
+	 * for the kernel.
+	 *
+	 * ACPI SRAT records all hotpluggable memory ranges. But before
+	 * SRAT is parsed, we don't know about it.
+	 *
+	 * The kernel image is loaded into memory at very early time. We
+	 * cannot prevent this anyway. So on NUMA system, we set any
+	 * node the kernel resides in as un-hotpluggable.
+	 *
+	 * Since on modern servers, one node could have double-digit
+	 * gigabytes memory, we can assume the memory around the kernel
+	 * image is also un-hotpluggable. So before SRAT is parsed, just
+	 * allocate memory near the kernel image to try the best to keep
+	 * the kernel away from hotpluggable memory.
+	 */
+	if (movable_node_is_enabled())
+		memblock_set_bottom_up(true);
+#endif
+
+	/*
+	 * At this point only the first megabyte is mapped for sure, the
+	 * rest of the memory cannot be used for memblock resizing
+	 */
+	memblock_set_current_limit(ISA_END_ADDRESS);
+
 	/*
 	 * The bootstrap memblock region count maximum is 128 entries
 	 * (INIT_MEMBLOCK_REGIONS), but EFI might pass us more E820 entries
diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c
index cebee31..4baadea 100644
--- a/arch/x86/kernel/setup.c
+++ b/arch/x86/kernel/setup.c
@@ -866,30 +866,6 @@ void __init setup_arch(char **cmdline_p)
 	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
-	 * cannot migrate the kernel pages. When memory hotplug is
-	 * enabled, we should prevent memblock from allocating memory
-	 * for the kernel.
-	 *
-	 * ACPI SRAT records all hotpluggable memory ranges. But before
-	 * SRAT is parsed, we don't know about it.
-	 *
-	 * The kernel image is loaded into memory at very early time. We
-	 * cannot prevent this anyway. So on NUMA system, we set any
-	 * node the kernel resides in as un-hotpluggable.
-	 *
-	 * Since on modern servers, one node could have double-digit
-	 * gigabytes memory, we can assume the memory around the kernel
-	 * image is also un-hotpluggable. So before SRAT is parsed, just
-	 * allocate memory near the kernel image to try the best to keep
-	 * the kernel away from hotpluggable memory.
-	 */
-	if (movable_node_is_enabled())
-		memblock_set_bottom_up(true);
-#endif
-
 	x86_report_nx();
 
 	apic_setup_apic_calls();
@@ -990,7 +966,6 @@ void __init setup_arch(char **cmdline_p)
 
 	cleanup_highmap();
 
-	memblock_set_current_limit(ISA_END_ADDRESS);
 	e820__memblock_setup();
 
 	/*