@@ -1839,6 +1839,18 @@
initcall functions. Useful for debugging built-in
modules and initcalls.
+ initramfs_async= [KNL]
+ Format: <bool>
+ Default: 1
+ This parameter controls whether the initramfs
+ image is unpacked asynchronously, concurrently
+ with devices being probed and
+ initialized. This should normally just work,
+ but as a debugging aid, one can get the
+ historical behaviour of the initramfs
+ unpacking being completed before device_ and
+ late_ initcalls.
+
initrd= [BOOT] Specify the location of the initial ramdisk
initrdmem= [KNL] Specify a physical address and size from which to
@@ -15,6 +15,7 @@
#include <linux/kernel_read_file.h>
#include <linux/module.h>
#include <linux/init.h>
+#include <linux/initrd.h>
#include <linux/timer.h>
#include <linux/vmalloc.h>
#include <linux/interrupt.h>
@@ -504,6 +505,7 @@ fw_get_filesystem_firmware(struct device
if (!path)
return -ENOMEM;
+ wait_for_initramfs();
for (i = 0; i < ARRAY_SIZE(fw_path); i++) {
size_t file_size = 0;
size_t *file_size_ptr = NULL;
@@ -20,8 +20,10 @@ extern void free_initrd_mem(unsigned lon
#ifdef CONFIG_BLK_DEV_INITRD
extern void __init reserve_initrd_mem(void);
+extern void wait_for_initramfs(void);
#else
static inline void __init reserve_initrd_mem(void) {}
+static inline void wait_for_initramfs(void) {}
#endif
extern phys_addr_t phys_initrd_start;
@@ -1,5 +1,6 @@
// SPDX-License-Identifier: GPL-2.0
#include <linux/init.h>
+#include <linux/async.h>
#include <linux/fs.h>
#include <linux/slab.h>
#include <linux/types.h>
@@ -541,6 +542,14 @@ static int __init keepinitrd_setup(char
__setup("keepinitrd", keepinitrd_setup);
#endif
+static bool __initdata initramfs_async = true;
+static int __init initramfs_async_setup(char *str)
+{
+ strtobool(str, &initramfs_async);
+ return 1;
+}
+__setup("initramfs_async=", initramfs_async_setup);
+
extern char __initramfs_start[];
extern unsigned long __initramfs_size;
#include <linux/initrd.h>
@@ -658,7 +667,7 @@ static void __init populate_initrd_image
}
#endif /* CONFIG_BLK_DEV_RAM */
-static int __init populate_rootfs(void)
+static void __init do_populate_rootfs(void *unused, async_cookie_t cookie)
{
/* Load the built in initramfs */
char *err = unpack_to_rootfs(__initramfs_start, __initramfs_size);
@@ -693,6 +702,33 @@ done:
initrd_end = 0;
flush_delayed_fput();
+}
+
+static ASYNC_DOMAIN_EXCLUSIVE(initramfs_domain);
+static async_cookie_t initramfs_cookie;
+
+void wait_for_initramfs(void)
+{
+ if (!initramfs_cookie) {
+ /*
+ * Something before rootfs_initcall wants to access
+ * the filesystem/initramfs. Probably a bug. Make a
+ * note, avoid deadlocking the machine, and let the
+ * caller's access fail as it used to.
+ */
+ pr_warn_once("wait_for_initramfs() called before rootfs_initcalls\n");
+ return;
+ }
+ async_synchronize_cookie_domain(initramfs_cookie + 1, &initramfs_domain);
+}
+EXPORT_SYMBOL_GPL(wait_for_initramfs);
+
+static int __init populate_rootfs(void)
+{
+ initramfs_cookie = async_schedule_domain(do_populate_rootfs, NULL,
+ &initramfs_domain);
+ if (!initramfs_async)
+ wait_for_initramfs();
return 0;
}
rootfs_initcall(populate_rootfs);
@@ -1561,6 +1561,7 @@ static noinline void __init kernel_init_
kunit_run_all_tests();
+ wait_for_initramfs();
console_on_rootfs();
/*
@@ -27,6 +27,7 @@
#include <linux/ptrace.h>
#include <linux/async.h>
#include <linux/uaccess.h>
+#include <linux/initrd.h>
#include <trace/events/module.h>
@@ -107,6 +108,7 @@ static int call_usermodehelper_exec_asyn
commit_creds(new);
+ wait_for_initramfs();
retval = kernel_execve(sub_info->path,
(const char *const *)sub_info->argv,
(const char *const *)sub_info->envp);