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/csky/mm/Makefile b/arch/csky/mm/Makefile
index c94ef64..efb7eba 100644
--- a/arch/csky/mm/Makefile
+++ b/arch/csky/mm/Makefile
@@ -1,8 +1,10 @@
 # SPDX-License-Identifier: GPL-2.0-only
 ifeq ($(CONFIG_CPU_HAS_CACHEV2),y)
 obj-y +=			cachev2.o
+CFLAGS_REMOVE_cachev2.o = $(CC_FLAGS_FTRACE)
 else
 obj-y +=			cachev1.o
+CFLAGS_REMOVE_cachev1.o = $(CC_FLAGS_FTRACE)
 endif
 
 obj-y +=			dma-mapping.o
diff --git a/arch/csky/mm/fault.c b/arch/csky/mm/fault.c
index f76618b..562c7f7 100644
--- a/arch/csky/mm/fault.c
+++ b/arch/csky/mm/fault.c
@@ -179,11 +179,14 @@
 bad_area_nosemaphore:
 	/* User mode accesses just cause a SIGSEGV */
 	if (user_mode(regs)) {
+		tsk->thread.trap_no = (regs->sr >> 16) & 0xff;
 		force_sig_fault(SIGSEGV, si_code, (void __user *)address);
 		return;
 	}
 
 no_context:
+	tsk->thread.trap_no = (regs->sr >> 16) & 0xff;
+
 	/* Are we prepared to handle this kernel fault? */
 	if (fixup_exception(regs))
 		return;
@@ -198,6 +201,8 @@
 	die_if_kernel("Oops", regs, write);
 
 out_of_memory:
+	tsk->thread.trap_no = (regs->sr >> 16) & 0xff;
+
 	/*
 	 * We ran out of memory, call the OOM killer, and return the userspace
 	 * (which will retry the fault, or kill us if we got oom-killed).
@@ -206,6 +211,8 @@
 	return;
 
 do_sigbus:
+	tsk->thread.trap_no = (regs->sr >> 16) & 0xff;
+
 	up_read(&mm->mmap_sem);
 
 	/* Kernel mode? Handle exceptions or die */
diff --git a/arch/csky/mm/init.c b/arch/csky/mm/init.c
index d4c2292..00e9627 100644
--- a/arch/csky/mm/init.c
+++ b/arch/csky/mm/init.c
@@ -31,6 +31,7 @@
 
 pgd_t swapper_pg_dir[PTRS_PER_PGD] __page_aligned_bss;
 pte_t invalid_pte_table[PTRS_PER_PTE] __page_aligned_bss;
+EXPORT_SYMBOL(invalid_pte_table);
 unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)]
 						__page_aligned_bss;
 EXPORT_SYMBOL(empty_zero_page);