diff --git a/arch/arm64/kernel/setup.c b/arch/arm64/kernel/setup.c
index d594ce9d5875..ca82e5d7f861 100644
--- a/arch/arm64/kernel/setup.c
+++ b/arch/arm64/kernel/setup.c
@@ -334,25 +334,6 @@ static void __init setup_machine_fdt(phys_addr_t dt_phys)
    }
 }

-/*
- * Limit the memory size that was specified via FDT.
- */
-static int __init early_mem(char *p)
-{
-   phys_addr_t limit;
-
-   if (!p)
-       return 1;
-
-   limit = memparse(p, &p) & PAGE_MASK;
-   pr_notice("Memory limited to %lldMB\n", limit >> 20);
-
-   memblock_enforce_memory_limit(limit);
-
-   return 0;
-}
-early_param("mem", early_mem);
-
 static void __init request_standard_resources(void)
 {
    struct memblock_region *region;
diff --git a/arch/arm64/mm/init.c b/arch/arm64/mm/init.c
index bed06465ed62..3ecc4997ed4e 100644
--- a/arch/arm64/mm/init.c
+++ b/arch/arm64/mm/init.c
@@ -138,10 +138,29 @@ static void arm64_memory_present(void)
 }
 #endif

+static phys_addr_t memory_limit = (phys_addr_t)ULLONG_MAX;
+
+/*
+ * Limit the memory size that was specified via FDT.
+ */
+static int __init early_mem(char *p)
+{
+   if (!p)
+       return 1;
+
+   memory_limit = memparse(p, &p) & PAGE_MASK;
+   pr_notice("Memory limited to %lldMB\n", memory_limit >> 20);
+
+   return 0;
+}
+early_param("mem", early_mem);
+
 void __init arm64_memblock_init(void)
 {
    phys_addr_t dma_phys_limit = 0;

+   memblock_enforce_memory_limit(memory_limit);
+
    /*
     * Register the kernel text, kernel data, initrd, and initial
     * pagetables with memblock.
diff --git a/arch/x86/boot/compressed/misc.h b/arch/x86/boot/compressed/misc.h
index 04477d68403f..4ece9e3579c0 100644
--- a/arch/x86/boot/compressed/misc.h
+++ b/arch/x86/boot/compressed/misc.h
@@ -7,6 +7,7 @@
  * we just keep it from happening
  */
 #undef CONFIG_PARAVIRT
+#undef CONFIG_PARAVIRT_SPINLOCKS
 #undef CONFIG_KASAN
 #ifdef CONFIG_X86_32
 #define _ASM_X86_DESC_H 1
diff --git a/include/linux/compiler-gcc.h b/include/linux/compiler-gcc.h
index b9c842a58fa5..3b645a0fef29 100644
--- a/include/linux/compiler-gcc.h
+++ b/include/linux/compiler-gcc.h
@@ -114,13 +114,14 @@
  * would be.
  * [...]
  */
-#define __pure         __attribute__((pure))
-#define __aligned(x)       __attribute__((aligned(x)))
-#define __printf(a, b)     __attribute__((format(printf, a, b)))
-#define __scanf(a, b)      __attribute__((format(scanf, a, b)))
-#define __attribute_const__    __attribute__((__const__))
-#define __maybe_unused     __attribute__((unused))
-#define __always_unused        __attribute__((unused))
+#define __pure             __attribute__((pure))
+#define __aligned(x)           __attribute__((aligned(x)))
+#define __printf(a, b)         __attribute__((format(printf, a, b)))
+#define __scanf(a, b)          __attribute__((format(scanf, a, b)))
+#define  noinline          __attribute__((noinline))
+#define __attribute_const__        __attribute__((__const__))
+#define __maybe_unused         __attribute__((unused))
+#define __always_unused            __attribute__((unused))

 /* gcc version specific checks */

diff --git a/known-bugs b/known-bugs
new file mode 100644
index 000000000000..9b8758452ffe
--- /dev/null
+++ b/known-bugs
@@ -0,0 +1,7 @@
+1, Kernel build error when ARCH=arm with multi_v7_defconfig+CONFIG_SMP=n
+   arch/arm/kernel/psci.c:287:115: error: redefinition of 'psci_init'
+  This bug start from commit dbcfee724255ae1 ARM: 8457/1: psci-smp is built only for SMP
+2, Kernel build error when ARCH=x86 with allmodconfig+CONFIG_OF=n or defconfig+CONFIG_KASAN=y
+   include/linux/kasan.h:21:14: error: conflicting types for 'kasan_zero_pud'
+   include/linux/kasan.h:20:14: error: conflicting types for 'kasan_zero_pmd'
+  This bug is due to KASAN feature backporting