Update Linux to v5.4.148

Sourced from [1]

[1] https://cdn.kernel.org/pub/linux/kernel/v5.x/linux-5.4.148.tar.gz

Change-Id: Ib3d26c5ba9b022e2e03533005c4fed4d7c30b61b
Signed-off-by: Olivier Deprez <olivier.deprez@arm.com>
diff --git a/arch/x86/kernel/crash.c b/arch/x86/kernel/crash.c
index eb651fb..0c319d0 100644
--- a/arch/x86/kernel/crash.c
+++ b/arch/x86/kernel/crash.c
@@ -24,6 +24,7 @@
 #include <linux/export.h>
 #include <linux/slab.h>
 #include <linux/vmalloc.h>
+#include <linux/memblock.h>
 
 #include <asm/processor.h>
 #include <asm/hardirq.h>
@@ -39,6 +40,7 @@
 #include <asm/virtext.h>
 #include <asm/intel_pt.h>
 #include <asm/crash.h>
+#include <asm/cmdline.h>
 
 /* Used while preparing memory map entries for second kernel */
 struct crash_memmap_data {
@@ -68,6 +70,19 @@
 	rcu_read_unlock();
 }
 
+/*
+ * When the crashkernel option is specified, only use the low
+ * 1M for the real mode trampoline.
+ */
+void __init crash_reserve_low_1M(void)
+{
+	if (cmdline_find_option(boot_command_line, "crashkernel", NULL, 0) < 0)
+		return;
+
+	memblock_reserve(0, 1<<20);
+	pr_info("Reserving the low 1M of memory for crashkernel\n");
+}
+
 #if defined(CONFIG_SMP) && defined(CONFIG_X86_LOCAL_APIC)
 
 static void kdump_nmi_callback(int cpu, struct pt_regs *regs)
@@ -349,7 +364,7 @@
 	struct crash_memmap_data cmd;
 	struct crash_mem *cmem;
 
-	cmem = vzalloc(sizeof(struct crash_mem));
+	cmem = vzalloc(struct_size(cmem, ranges, 1));
 	if (!cmem)
 		return -ENOMEM;