linux-kernel - [PATCH v21 8/9] mm: memory_hotplug: disable memmap_on_memory when hugetlb_free

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]

Date:   Sun, 25 Apr 2021 15:07:51 +0800
From:   Muchun Song <songmuchun@...edance.com>
To:     corbet@....net, mike.kravetz@...cle.com, tglx@...utronix.de,
        mingo@...hat.com, bp@...en8.de, x86@...nel.org, hpa@...or.com,
        dave.hansen@...ux.intel.com, luto@...nel.org, peterz@...radead.org,
        viro@...iv.linux.org.uk, akpm@...ux-foundation.org,
        paulmck@...nel.org, pawan.kumar.gupta@...ux.intel.com,
        rdunlap@...radead.org, oneukum@...e.com, anshuman.khandual@....com,
        jroedel@...e.de, almasrymina@...gle.com, rientjes@...gle.com,
        willy@...radead.org, osalvador@...e.de, mhocko@...e.com,
        song.bao.hua@...ilicon.com, david@...hat.com,
        naoya.horiguchi@....com, joao.m.martins@...cle.com
Cc:     duanxiongchun@...edance.com, fam.zheng@...edance.com,
        zhengqi.arch@...edance.com, linux-doc@...r.kernel.org,
        linux-kernel@...r.kernel.org, linux-mm@...ck.org,
        linux-fsdevel@...r.kernel.org,
        Muchun Song <songmuchun@...edance.com>
Subject: [PATCH v21 8/9] mm: memory_hotplug: disable memmap_on_memory when hugetlb_free_vmemmap enabled

The parameter of memory_hotplug.memmap_on_memory is not compatible with
hugetlb_free_vmemmap. So disable it when hugetlb_free_vmemmap is
enabled.

Signed-off-by: Muchun Song <songmuchun@...edance.com>
---
 Documentation/admin-guide/kernel-parameters.txt | 8 ++++++++
 drivers/acpi/acpi_memhotplug.c                  | 1 +
 mm/memory_hotplug.c                             | 1 +
 3 files changed, 10 insertions(+)

diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
index 3cc19cb78b85..8181345e996a 100644
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt
@@ -1638,6 +1638,10 @@
 			on:  enable the feature
 			off: disable the feature
 
+			This is not compatible with memory_hotplug.memmap_on_memory.
+			If both parameters are enabled, hugetlb_free_vmemmap takes
+			precedence over memory_hotplug.memmap_on_memory.
+
 	hung_task_panic=
 			[KNL] Should the hung task detector generate panics.
 			Format: 0 | 1
@@ -2904,6 +2908,10 @@
 			Note that even when enabled, there are a few cases where
 			the feature is not effective.
 
+			This is not compatible with hugetlb_free_vmemmap. If
+			both parameters are enabled, hugetlb_free_vmemmap takes
+			precedence over memory_hotplug.memmap_on_memory.
+
 	memtest=	[KNL,X86,ARM,PPC,RISCV] Enable memtest
 			Format: <integer>
 			default : 0 <disable>
diff --git a/drivers/acpi/acpi_memhotplug.c b/drivers/acpi/acpi_memhotplug.c
index 8cc195c4c861..0d7f595ee441 100644
--- a/drivers/acpi/acpi_memhotplug.c
+++ b/drivers/acpi/acpi_memhotplug.c
@@ -15,6 +15,7 @@
 #include <linux/acpi.h>
 #include <linux/memory.h>
 #include <linux/memory_hotplug.h>
+#include <linux/hugetlb.h>
 
 #include "internal.h"
 
diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c
index 16b3a7a1db8c..6512e6f641bb 100644
--- a/mm/memory_hotplug.c
+++ b/mm/memory_hotplug.c
@@ -1052,6 +1052,7 @@ bool mhp_supports_memmap_on_memory(unsigned long size)
 	 *       populate a single PMD.
 	 */
 	return memmap_on_memory &&
+	       !is_hugetlb_free_vmemmap_enabled() &&
 	       IS_ENABLED(CONFIG_MHP_MEMMAP_ON_MEMORY) &&
 	       size == memory_block_size_bytes() &&
 	       IS_ALIGNED(vmemmap_size, PMD_SIZE) &&
-- 
2.11.0