Re: [PATCH v2] init: consolidate trap_init()

From: Helge Deller
Date: Sun Aug 22 2021 - 15:51:49 EST


On 4/14/21 12:00 PM, Jisheng Zhang wrote:
Many architectures implement the trap_init() as NOP, since there is
no such default for trap_init(), this empty stub is duplicated among
these architectures. Provide a generic but weak NOP implementation
to drop the empty stubs of trap_init() in these architectures.

The alpha, microblaze and sparc32 have real trap_init() implementation
but the __init marker is missing, so add it to these three platforms.

Signed-off-by: Jisheng Zhang <Jisheng.Zhang@xxxxxxxxxxxxx>
---
Since v1:
- add __init marker to trap_init() for alpha, microblaze and sparc32
- adjust the generic weak NOP trap_init() location to make it sits with
other NOP implementations together

arch/alpha/kernel/traps.c | 2 +-
arch/arc/kernel/traps.c | 5 -----
arch/arm/kernel/traps.c | 5 -----
arch/h8300/kernel/traps.c | 13 -------------
arch/hexagon/kernel/traps.c | 4 ----
arch/microblaze/kernel/traps.c | 2 +-
arch/nds32/kernel/traps.c | 5 -----
arch/nios2/kernel/traps.c | 5 -----
arch/openrisc/kernel/traps.c | 5 -----
arch/parisc/kernel/traps.c | 4 ----
arch/powerpc/kernel/traps.c | 5 -----
arch/riscv/kernel/traps.c | 5 -----
arch/sparc/kernel/traps_32.c | 2 +-
arch/um/kernel/trap.c | 4 ----
init/main.c | 2 ++
15 files changed, 5 insertions(+), 63 deletions(-)


For parisc:

Acked-by: Helge Deller <deller@xxxxxx> # parisc

Thanks!
Helge


diff --git a/arch/alpha/kernel/traps.c b/arch/alpha/kernel/traps.c
index 921d4b6e4d95..96b203199c6c 100644
--- a/arch/alpha/kernel/traps.c
+++ b/arch/alpha/kernel/traps.c
@@ -973,7 +973,7 @@ do_entUnaUser(void __user * va, unsigned long opcode,
return;
}

-void
+void __init
trap_init(void)
{
/* Tell PAL-code what global pointer we want in the kernel. */
diff --git a/arch/arc/kernel/traps.c b/arch/arc/kernel/traps.c
index 57235e5c0cea..6b83e3f2b41c 100644
--- a/arch/arc/kernel/traps.c
+++ b/arch/arc/kernel/traps.c
@@ -20,11 +20,6 @@
#include <asm/unaligned.h>
#include <asm/kprobes.h>

-void __init trap_init(void)
-{
- return;
-}
-
void die(const char *str, struct pt_regs *regs, unsigned long address)
{
show_kernel_fault_diag(str, regs, address);
diff --git a/arch/arm/kernel/traps.c b/arch/arm/kernel/traps.c
index 17d5a785df28..9baccef20392 100644
--- a/arch/arm/kernel/traps.c
+++ b/arch/arm/kernel/traps.c
@@ -780,11 +780,6 @@ void abort(void)
panic("Oops failed to kill thread");
}

-void __init trap_init(void)
-{
- return;
-}
-
#ifdef CONFIG_KUSER_HELPERS
static void __init kuser_init(void *vectors)
{
diff --git a/arch/h8300/kernel/traps.c b/arch/h8300/kernel/traps.c
index 5d8b969cd8f3..c3a3ebf77fbb 100644
--- a/arch/h8300/kernel/traps.c
+++ b/arch/h8300/kernel/traps.c
@@ -30,19 +30,6 @@

static DEFINE_SPINLOCK(die_lock);

-/*
- * this must be called very early as the kernel might
- * use some instruction that are emulated on the 060
- */
-
-void __init base_trap_init(void)
-{
-}
-
-void __init trap_init(void)
-{
-}
-
asmlinkage void set_esp0(unsigned long ssp)
{
current->thread.esp0 = ssp;
diff --git a/arch/hexagon/kernel/traps.c b/arch/hexagon/kernel/traps.c
index 904134b37232..edfc35dafeb1 100644
--- a/arch/hexagon/kernel/traps.c
+++ b/arch/hexagon/kernel/traps.c
@@ -28,10 +28,6 @@
#define TRAP_SYSCALL 1
#define TRAP_DEBUG 0xdb

-void __init trap_init(void)
-{
-}
-
#ifdef CONFIG_GENERIC_BUG
/* Maybe should resemble arch/sh/kernel/traps.c ?? */
int is_valid_bugaddr(unsigned long addr)
diff --git a/arch/microblaze/kernel/traps.c b/arch/microblaze/kernel/traps.c
index 94b6fe93147d..7c15704fe56e 100644
--- a/arch/microblaze/kernel/traps.c
+++ b/arch/microblaze/kernel/traps.c
@@ -18,7 +18,7 @@
#include <asm/exceptions.h>
#include <asm/unwind.h>

-void trap_init(void)
+void __init trap_init(void)
{
__enable_hw_exceptions();
}
diff --git a/arch/nds32/kernel/traps.c b/arch/nds32/kernel/traps.c
index ee0d9ae192a5..f06421c645af 100644
--- a/arch/nds32/kernel/traps.c
+++ b/arch/nds32/kernel/traps.c
@@ -183,11 +183,6 @@ void __pgd_error(const char *file, int line, unsigned long val)
}

extern char *exception_vector, *exception_vector_end;
-void __init trap_init(void)
-{
- return;
-}
-
void __init early_trap_init(void)
{
unsigned long ivb = 0;
diff --git a/arch/nios2/kernel/traps.c b/arch/nios2/kernel/traps.c
index b172da4eb1a9..596986a74a26 100644
--- a/arch/nios2/kernel/traps.c
+++ b/arch/nios2/kernel/traps.c
@@ -105,11 +105,6 @@ void show_stack(struct task_struct *task, unsigned long *stack,
printk("%s\n", loglvl);
}

-void __init trap_init(void)
-{
- /* Nothing to do here */
-}
-
/* Breakpoint handler */
asmlinkage void breakpoint_c(struct pt_regs *fp)
{
diff --git a/arch/openrisc/kernel/traps.c b/arch/openrisc/kernel/traps.c
index 4d61333c2623..aa1e709405ac 100644
--- a/arch/openrisc/kernel/traps.c
+++ b/arch/openrisc/kernel/traps.c
@@ -231,11 +231,6 @@ void unhandled_exception(struct pt_regs *regs, int ea, int vector)
die("Oops", regs, 9);
}

-void __init trap_init(void)
-{
- /* Nothing needs to be done */
-}
-
asmlinkage void do_trap(struct pt_regs *regs, unsigned long address)
{
force_sig_fault(SIGTRAP, TRAP_BRKPT, (void __user *)regs->pc);
diff --git a/arch/parisc/kernel/traps.c b/arch/parisc/kernel/traps.c
index 8d8441d4562a..747c328fb886 100644
--- a/arch/parisc/kernel/traps.c
+++ b/arch/parisc/kernel/traps.c
@@ -859,7 +859,3 @@ void __init early_trap_init(void)

initialize_ivt(&fault_vector_20);
}
-
-void __init trap_init(void)
-{
-}
diff --git a/arch/powerpc/kernel/traps.c b/arch/powerpc/kernel/traps.c
index a44a30b0688c..e952bee89684 100644
--- a/arch/powerpc/kernel/traps.c
+++ b/arch/powerpc/kernel/traps.c
@@ -2207,11 +2207,6 @@ DEFINE_INTERRUPT_HANDLER(kernel_bad_stack)
die("Bad kernel stack pointer", regs, SIGABRT);
}

-void __init trap_init(void)
-{
-}
-
-
#ifdef CONFIG_PPC_EMULATED_STATS

#define WARN_EMULATED_SETUP(type) .type = { .name = #type }
diff --git a/arch/riscv/kernel/traps.c b/arch/riscv/kernel/traps.c
index 0879b5df11b9..b3f3d84de779 100644
--- a/arch/riscv/kernel/traps.c
+++ b/arch/riscv/kernel/traps.c
@@ -194,8 +194,3 @@ int is_valid_bugaddr(unsigned long pc)
return ((insn & __COMPRESSED_INSN_MASK) == __BUG_INSN_16);
}
#endif /* CONFIG_GENERIC_BUG */
-
-/* stvec & scratch is already set from head.S */
-void trap_init(void)
-{
-}
diff --git a/arch/sparc/kernel/traps_32.c b/arch/sparc/kernel/traps_32.c
index 247a0d9683b2..c4df20ec01e2 100644
--- a/arch/sparc/kernel/traps_32.c
+++ b/arch/sparc/kernel/traps_32.c
@@ -365,7 +365,7 @@ EXPORT_SYMBOL(do_BUG);
* up here so that timer interrupts work during initialization.
*/

-void trap_init(void)
+void __init trap_init(void)
{
extern void thread_info_offsets_are_bolixed_pete(void);

diff --git a/arch/um/kernel/trap.c b/arch/um/kernel/trap.c
index ad12f78bda7e..3198c4767387 100644
--- a/arch/um/kernel/trap.c
+++ b/arch/um/kernel/trap.c
@@ -311,7 +311,3 @@ void winch(int sig, struct siginfo *unused_si, struct uml_pt_regs *regs)
{
do_IRQ(WINCH_IRQ, regs);
}
-
-void trap_init(void)
-{
-}
diff --git a/init/main.c b/init/main.c
index 53b278845b88..8d14674c4e00 100644
--- a/init/main.c
+++ b/init/main.c
@@ -779,6 +779,8 @@ void __init __weak poking_init(void) { }

void __init __weak pgtable_cache_init(void) { }

+void __init __weak trap_init(void) { }
+
bool initcall_debug;
core_param(initcall_debug, initcall_debug, bool, 0644);