kexec-boot: document memfd/tmpfs requirement; enable CONFIG_TMPFS/CONFIG_MEMFD_CREATE in linux configs

tlaurion · tlaurion · commit dc6f296cc3ee · 2026-02-02T13:19:22.000-05:00
Signed-off-by: Thierry Laurion &lt;insurgo@riseup.net&gt;
diff --git a/config/linux-c216.config b/config/linux-c216.config
@@ -2523,7 +2523,8 @@ CONFIG_PROC_SYSCTL=y
 CONFIG_PROC_PID_ARCH_STATUS=y
 CONFIG_KERNFS=y
 CONFIG_SYSFS=y
-# CONFIG_TMPFS is not set
+CONFIG_TMPFS=y
+CONFIG_MEMFD_CREATE=y
 # CONFIG_HUGETLBFS is not set
 CONFIG_ARCH_WANT_HUGETLB_PAGE_OPTIMIZE_VMEMMAP=y
 CONFIG_ARCH_HAS_GIGANTIC_PAGE=y
diff --git a/config/linux-kgpe-d16_server-whiptail.config b/config/linux-kgpe-d16_server-whiptail.config
@@ -2763,7 +2763,8 @@ CONFIG_PROC_SYSCTL=y
 CONFIG_PROC_PID_ARCH_STATUS=y
 CONFIG_KERNFS=y
 CONFIG_SYSFS=y
-# CONFIG_TMPFS is not set
+CONFIG_TMPFS=y
+CONFIG_MEMFD_CREATE=y
 # CONFIG_HUGETLBFS is not set
 CONFIG_ARCH_WANT_HUGETLB_PAGE_OPTIMIZE_VMEMMAP=y
 CONFIG_ARCH_HAS_GIGANTIC_PAGE=y
diff --git a/config/linux-kgpe-d16_server.config b/config/linux-kgpe-d16_server.config
@@ -2763,7 +2763,8 @@ CONFIG_PROC_SYSCTL=y
 CONFIG_PROC_PID_ARCH_STATUS=y
 CONFIG_KERNFS=y
 CONFIG_SYSFS=y
-# CONFIG_TMPFS is not set
+CONFIG_TMPFS=y
+CONFIG_MEMFD_CREATE=y
 # CONFIG_HUGETLBFS is not set
 CONFIG_ARCH_WANT_HUGETLB_PAGE_OPTIMIZE_VMEMMAP=y
 CONFIG_ARCH_HAS_GIGANTIC_PAGE=y
diff --git a/config/linux-kgpe-d16_workstation.config b/config/linux-kgpe-d16_workstation.config
@@ -2987,7 +2987,8 @@ CONFIG_PROC_SYSCTL=y
 CONFIG_PROC_PID_ARCH_STATUS=y
 CONFIG_KERNFS=y
 CONFIG_SYSFS=y
-# CONFIG_TMPFS is not set
+CONFIG_TMPFS=y
+CONFIG_MEMFD_CREATE=y
 # CONFIG_HUGETLBFS is not set
 CONFIG_ARCH_WANT_HUGETLB_PAGE_OPTIMIZE_VMEMMAP=y
 CONFIG_ARCH_HAS_GIGANTIC_PAGE=y
diff --git a/config/linux-librem_common-6.1.8.config b/config/linux-librem_common-6.1.8.config
@@ -2476,7 +2476,8 @@ CONFIG_PROC_SYSCTL=y
 CONFIG_PROC_PID_ARCH_STATUS=y
 CONFIG_KERNFS=y
 CONFIG_SYSFS=y
-# CONFIG_TMPFS is not set
+CONFIG_TMPFS=y
+CONFIG_MEMFD_CREATE=y
 # CONFIG_HUGETLBFS is not set
 CONFIG_ARCH_WANT_HUGETLB_PAGE_OPTIMIZE_VMEMMAP=y
 CONFIG_ARCH_HAS_GIGANTIC_PAGE=y
diff --git a/config/linux-linuxboot.config b/config/linux-linuxboot.config
@@ -268,7 +268,8 @@ CONFIG_MSDOS_FS=y
 CONFIG_VFAT_FS=y
 CONFIG_PROC_SYSCTL=y
 # CONFIG_PROC_PAGE_MONITOR is not set
-CONFIG_TMPFS=n
+CONFIG_TMPFS=y
+CONFIG_MEMFD_CREATE=y
 CONFIG_HUGETLBFS=y
 CONFIG_EFIVAR_FS=y
 # CONFIG_MISC_FILESYSTEMS is not set
diff --git a/config/linux-novacustom-common.config b/config/linux-novacustom-common.config
@@ -2748,7 +2748,8 @@ CONFIG_PROC_SYSCTL=y
 CONFIG_PROC_PID_ARCH_STATUS=y
 CONFIG_KERNFS=y
 CONFIG_SYSFS=y
-# CONFIG_TMPFS is not set
+CONFIG_TMPFS=y
+CONFIG_MEMFD_CREATE=y
 # CONFIG_HUGETLBFS is not set
 CONFIG_ARCH_WANT_HUGETLB_PAGE_OPTIMIZE_VMEMMAP=y
 CONFIG_ARCH_HAS_GIGANTIC_PAGE=y
diff --git a/config/linux-qemu.config b/config/linux-qemu.config
@@ -2772,7 +2772,8 @@ CONFIG_PROC_SYSCTL=y
 CONFIG_PROC_PID_ARCH_STATUS=y
 CONFIG_KERNFS=y
 CONFIG_SYSFS=y
-# CONFIG_TMPFS is not set
+CONFIG_TMPFS=y
+CONFIG_MEMFD_CREATE=y
 # CONFIG_HUGETLBFS is not set
 CONFIG_ARCH_WANT_HUGETLB_PAGE_OPTIMIZE_VMEMMAP=y
 CONFIG_ARCH_HAS_GIGANTIC_PAGE=y
diff --git a/config/linux-t440p.config b/config/linux-t440p.config
@@ -2734,7 +2734,8 @@ CONFIG_PROC_SYSCTL=y
 CONFIG_PROC_PID_ARCH_STATUS=y
 CONFIG_KERNFS=y
 CONFIG_SYSFS=y
-# CONFIG_TMPFS is not set
+CONFIG_TMPFS=y
+CONFIG_MEMFD_CREATE=y
 # CONFIG_HUGETLBFS is not set
 CONFIG_ARCH_WANT_HUGETLB_PAGE_OPTIMIZE_VMEMMAP=y
 CONFIG_ARCH_HAS_GIGANTIC_PAGE=y
diff --git a/config/linux-t480.config b/config/linux-t480.config
@@ -2480,7 +2480,8 @@ CONFIG_PROC_SYSCTL=y
 CONFIG_PROC_PID_ARCH_STATUS=y
 CONFIG_KERNFS=y
 CONFIG_SYSFS=y
-# CONFIG_TMPFS is not set
+CONFIG_TMPFS=y
+CONFIG_MEMFD_CREATE=y
 # CONFIG_HUGETLBFS is not set
 CONFIG_ARCH_WANT_HUGETLB_PAGE_OPTIMIZE_VMEMMAP=y
 CONFIG_ARCH_HAS_GIGANTIC_PAGE=y
diff --git a/config/linux-talos-2.config b/config/linux-talos-2.config
@@ -734,7 +734,7 @@ CONFIG_VM_EVENT_COUNTERS=y
 # CONFIG_GUP_TEST is not set
 # CONFIG_DMAPOOL_TEST is not set
 CONFIG_ARCH_HAS_PTE_SPECIAL=y
-# CONFIG_MEMFD_CREATE is not set
+CONFIG_MEMFD_CREATE=y
 # CONFIG_ANON_VMA_NAME is not set
 # CONFIG_USERFAULTFD is not set
 # CONFIG_LRU_GEN is not set
@@ -3033,7 +3033,8 @@ CONFIG_PROC_PAGE_MONITOR=y
 # CONFIG_PROC_CHILDREN is not set
 CONFIG_KERNFS=y
 CONFIG_SYSFS=y
-# CONFIG_TMPFS is not set
+CONFIG_TMPFS=y
+CONFIG_MEMFD_CREATE=y
 CONFIG_ARCH_SUPPORTS_HUGETLBFS=y
 # CONFIG_HUGETLBFS is not set
 CONFIG_ARCH_HAS_GIGANTIC_PAGE=y
diff --git a/config/linux-w541.config b/config/linux-w541.config
@@ -2734,7 +2734,8 @@ CONFIG_PROC_SYSCTL=y
 CONFIG_PROC_PID_ARCH_STATUS=y
 CONFIG_KERNFS=y
 CONFIG_SYSFS=y
-# CONFIG_TMPFS is not set
+CONFIG_TMPFS=y
+CONFIG_MEMFD_CREATE=y
 # CONFIG_HUGETLBFS is not set
 CONFIG_ARCH_WANT_HUGETLB_PAGE_OPTIMIZE_VMEMMAP=y
 CONFIG_ARCH_HAS_GIGANTIC_PAGE=y
diff --git a/config/linux-x230-flash.config b/config/linux-x230-flash.config
@@ -2111,7 +2111,8 @@ CONFIG_PROC_SYSCTL=y
 CONFIG_PROC_PID_ARCH_STATUS=y
 CONFIG_KERNFS=y
 CONFIG_SYSFS=y
-# CONFIG_TMPFS is not set
+CONFIG_TMPFS=y
+CONFIG_MEMFD_CREATE=y
 # CONFIG_HUGETLBFS is not set
 CONFIG_ARCH_WANT_HUGETLB_PAGE_OPTIMIZE_VMEMMAP=y
 CONFIG_ARCH_HAS_GIGANTIC_PAGE=y
diff --git a/config/linux-x230-legacy.config b/config/linux-x230-legacy.config
@@ -2290,7 +2290,8 @@ CONFIG_PROC_SYSCTL=y
 CONFIG_PROC_PID_ARCH_STATUS=y
 CONFIG_KERNFS=y
 CONFIG_SYSFS=y
-# CONFIG_TMPFS is not set
+CONFIG_TMPFS=y
+CONFIG_MEMFD_CREATE=y
 # CONFIG_HUGETLBFS is not set
 CONFIG_ARCH_WANT_HUGETLB_PAGE_OPTIMIZE_VMEMMAP=y
 CONFIG_ARCH_HAS_GIGANTIC_PAGE=y
diff --git a/config/linux-x230-maximized.config b/config/linux-x230-maximized.config
@@ -2523,7 +2523,8 @@ CONFIG_PROC_SYSCTL=y
 CONFIG_PROC_PID_ARCH_STATUS=y
 CONFIG_KERNFS=y
 CONFIG_SYSFS=y
-# CONFIG_TMPFS is not set
+CONFIG_TMPFS=y
+CONFIG_MEMFD_CREATE=y
 # CONFIG_HUGETLBFS is not set
 CONFIG_ARCH_WANT_HUGETLB_PAGE_OPTIMIZE_VMEMMAP=y
 CONFIG_ARCH_HAS_GIGANTIC_PAGE=y
diff --git a/initrd/bin/kexec-boot b/initrd/bin/kexec-boot
@@ -1,5 +1,11 @@
 #!/bin/bash
 # Launches kexec from saved configuration entries
+#
+# NOTE: `kexec-boot` may use memfd-backed initrds and the kexec syscall/file-loader paths.
+# To avoid loader placement/copy errors (e.g., "Failed to copy decompressed buf") ensure
+# kernels intended to run `kexec --kexec-syscall --load ... --initrd=<memfd>` have:
+#   CONFIG_TMPFS=y
+#   CONFIG_MEMFD_CREATE=y
 set -e -o pipefail
 . /tmp/config
 . /etc/functions
