[PATCH 02/10] exit: Add and use make_task_dead.

From: Eric W. Biederman <hidden>
Date: 2021-12-08 20:26:21
Also in: lkml
Subsystem: alpha port, arm port, arm64 port (aarch64 architecture), c-sky architecture, linux for powerpc (32-bit and 64-bit), m68k architecture, microblaze architecture, mips, nios2 architecture, objtool, openrisc architecture, parisc architecture, qualcomm hexagon architecture, risc-v architecture, s390 architecture, sparc + ultrasparc (sparc/sparc64), superh, tensilica xtensa port (xtensa), the rest, x86 architecture (32-bit and 64-bit), x86 entry code, x86 stack unwinding · Maintainers: Richard Henderson, Matt Turner, Magnus Lindholm, Russell King, Catalin Marinas, Will Deacon, Guo Ren, Madhavan Srinivasan, Michael Ellerman, Geert Uytterhoeven, Michal Simek, Thomas Bogendoerfer, Dinh Nguyen, Simon Schuster, Josh Poimboeuf, Peter Zijlstra, Jonas Bonn, Stefan Kristiansson, Stafford Horne, "James E.J. Bottomley", Helge Deller, Brian Cain, Paul Walmsley, Palmer Dabbelt, Albert Ou, Heiko Carstens, Vasily Gorbik, Alexander Gordeev, "David S. Miller", Andreas Larsson, Yoshinori Sato, Rich Felker, John Paul Adrian Glaubitz, Chris Zankel, Max Filippov, Linus Torvalds, Thomas Gleixner, Ingo Molnar, Borislav Petkov, Dave Hansen, Andy Lutomirski

There are two big uses of do_exit.  The first is it's design use to be
the guts of the exit(2) system call.  The second use is to terminate
a task after something catastrophic has happened like a NULL pointer
in kernel code.

Add a function make_task_dead that is initialy exactly the same as
do_exit to cover the cases where do_exit is called to handle
catastrophic failure.  In time this can probably be reduced to just a
light wrapper around do_task_dead. For now keep it exactly the same so
that there will be no behavioral differences introducing this new
concept.

Replace all of the uses of do_exit that use it for catastraphic
task cleanup with make_task_dead to make it clear what the code
is doing.

As part of this rename rewind_stack_do_exit
rewind_stack_and_make_dead.

Signed-off-by: "Eric W. Biederman" <redacted>
---
 arch/alpha/kernel/traps.c           | 6 +++---
 arch/alpha/mm/fault.c               | 2 +-
 arch/arm/kernel/traps.c             | 2 +-
 arch/arm/mm/fault.c                 | 2 +-
 arch/arm64/kernel/traps.c           | 2 +-
 arch/arm64/mm/fault.c               | 2 +-
 arch/csky/abiv1/alignment.c         | 2 +-
 arch/csky/kernel/traps.c            | 2 +-
 arch/csky/mm/fault.c                | 2 +-
 arch/h8300/kernel/traps.c           | 2 +-
 arch/h8300/mm/fault.c               | 2 +-
 arch/hexagon/kernel/traps.c         | 2 +-
 arch/ia64/kernel/mca_drv.c          | 2 +-
 arch/ia64/kernel/traps.c            | 2 +-
 arch/ia64/mm/fault.c                | 2 +-
 arch/m68k/kernel/traps.c            | 2 +-
 arch/m68k/mm/fault.c                | 2 +-
 arch/microblaze/kernel/exceptions.c | 4 ++--
 arch/mips/kernel/traps.c            | 2 +-
 arch/nds32/kernel/fpu.c             | 2 +-
 arch/nds32/kernel/traps.c           | 8 ++++----
 arch/nios2/kernel/traps.c           | 4 ++--
 arch/openrisc/kernel/traps.c        | 2 +-
 arch/parisc/kernel/traps.c          | 2 +-
 arch/powerpc/kernel/traps.c         | 8 ++++----
 arch/riscv/kernel/traps.c           | 2 +-
 arch/riscv/mm/fault.c               | 2 +-
 arch/s390/kernel/dumpstack.c        | 2 +-
 arch/s390/kernel/nmi.c              | 2 +-
 arch/sh/kernel/traps.c              | 2 +-
 arch/sparc/kernel/traps_32.c        | 4 +---
 arch/sparc/kernel/traps_64.c        | 4 +---
 arch/x86/entry/entry_32.S           | 6 +++---
 arch/x86/entry/entry_64.S           | 6 +++---
 arch/x86/kernel/dumpstack.c         | 4 ++--
 arch/xtensa/kernel/traps.c          | 2 +-
 include/linux/sched/task.h          | 1 +
 kernel/exit.c                       | 9 +++++++++
 tools/objtool/check.c               | 3 ++-
 39 files changed, 63 insertions(+), 56 deletions(-)

diff --git a/arch/alpha/kernel/traps.c b/arch/alpha/kernel/traps.c
index 2ae34702456c..8a66fe544c69 100644
--- a/arch/alpha/kernel/traps.c
+++ b/arch/alpha/kernel/traps.c

@@ -190,7 +190,7 @@ die_if_kernel(char * str, struct pt_regs *regs, long err, unsigned long *r9_15)
 		local_irq_enable();
 		while (1);
 	}
-	do_exit(SIGSEGV);
+	make_task_dead(SIGSEGV);
 }
 
 #ifndef CONFIG_MATHEMU

@@ -575,7 +575,7 @@ do_entUna(void * va, unsigned long opcode, unsigned long reg,
 
 	printk("Bad unaligned kernel access at %016lx: %p %lx %lu\n",
 		pc, va, opcode, reg);
-	do_exit(SIGSEGV);
+	make_task_dead(SIGSEGV);
 
 got_exception:
 	/* Ok, we caught the exception, but we don't want it.  Is there

@@ -630,7 +630,7 @@ do_entUna(void * va, unsigned long opcode, unsigned long reg,
 		local_irq_enable();
 		while (1);
 	}
-	do_exit(SIGSEGV);
+	make_task_dead(SIGSEGV);
 }
 
 /*

diff --git a/arch/alpha/mm/fault.c b/arch/alpha/mm/fault.c
index eee5102c3d88..e9193d52222e 100644
--- a/arch/alpha/mm/fault.c
+++ b/arch/alpha/mm/fault.c

@@ -204,7 +204,7 @@ do_page_fault(unsigned long address, unsigned long mmcsr,
 	printk(KERN_ALERT "Unable to handle kernel paging request at "
 	       "virtual address %016lx\n", address);
 	die_if_kernel("Oops", regs, cause, (unsigned long*)regs - 16);
-	do_exit(SIGKILL);
+	make_task_dead(SIGKILL);
 
 	/* We ran out of memory, or some other thing happened to us that
 	   made us unable to handle the page fault gracefully.  */

diff --git a/arch/arm/kernel/traps.c b/arch/arm/kernel/traps.c
index 195dff58bafc..b4bd2e5f17c1 100644
--- a/arch/arm/kernel/traps.c
+++ b/arch/arm/kernel/traps.c

@@ -333,7 +333,7 @@ static void oops_end(unsigned long flags, struct pt_regs *regs, int signr)
 	if (panic_on_oops)
 		panic("Fatal exception");
 	if (signr)
-		do_exit(signr);
+		make_task_dead(signr);
 }
 
 /*

diff --git a/arch/arm/mm/fault.c b/arch/arm/mm/fault.c
index bc8779d54a64..bf1a0c618c49 100644
--- a/arch/arm/mm/fault.c
+++ b/arch/arm/mm/fault.c

@@ -111,7 +111,7 @@ static void die_kernel_fault(const char *msg, struct mm_struct *mm,
 	show_pte(KERN_ALERT, mm, addr);
 	die("Oops", regs, fsr);
 	bust_spinlocks(0);
-	do_exit(SIGKILL);
+	make_task_dead(SIGKILL);
 }
 
 /*

diff --git a/arch/arm64/kernel/traps.c b/arch/arm64/kernel/traps.c
index 7b21213a570f..bdd456e4e7f4 100644
--- a/arch/arm64/kernel/traps.c
+++ b/arch/arm64/kernel/traps.c

@@ -235,7 +235,7 @@ void die(const char *str, struct pt_regs *regs, int err)
 	raw_spin_unlock_irqrestore(&die_lock, flags);
 
 	if (ret != NOTIFY_STOP)
-		do_exit(SIGSEGV);
+		make_task_dead(SIGSEGV);
 }
 
 static void arm64_show_signal(int signo, const char *str)

diff --git a/arch/arm64/mm/fault.c b/arch/arm64/mm/fault.c
index 9ae24e3b72be..11a28cace2d2 100644
--- a/arch/arm64/mm/fault.c
+++ b/arch/arm64/mm/fault.c

@@ -302,7 +302,7 @@ static void die_kernel_fault(const char *msg, unsigned long addr,
 	show_pte(addr);
 	die("Oops", regs, esr);
 	bust_spinlocks(0);
-	do_exit(SIGKILL);
+	make_task_dead(SIGKILL);
 }
 
 #ifdef CONFIG_KASAN_HW_TAGS

diff --git a/arch/csky/abiv1/alignment.c b/arch/csky/abiv1/alignment.c
index cb2a0d94a144..5e2fb45d605c 100644
--- a/arch/csky/abiv1/alignment.c
+++ b/arch/csky/abiv1/alignment.c

@@ -294,7 +294,7 @@ void csky_alignment(struct pt_regs *regs)
 				__func__, opcode, rz, rx, imm, addr);
 		show_regs(regs);
 		bust_spinlocks(0);
-		do_exit(SIGKILL);
+		make_dead_task(SIGKILL);
 	}
 
 	force_sig_fault(SIGBUS, BUS_ADRALN, (void __user *)addr);

diff --git a/arch/csky/kernel/traps.c b/arch/csky/kernel/traps.c
index e5fbf8653a21..88a47035b925 100644
--- a/arch/csky/kernel/traps.c
+++ b/arch/csky/kernel/traps.c

@@ -109,7 +109,7 @@ void die(struct pt_regs *regs, const char *str)
 	if (panic_on_oops)
 		panic("Fatal exception");
 	if (ret != NOTIFY_STOP)
-		do_exit(SIGSEGV);
+		make_dead_task(SIGSEGV);
 }
 
 void do_trap(struct pt_regs *regs, int signo, int code, unsigned long addr)

diff --git a/arch/csky/mm/fault.c b/arch/csky/mm/fault.c
index 466ad949818a..7215a46b6b8e 100644
--- a/arch/csky/mm/fault.c
+++ b/arch/csky/mm/fault.c

@@ -67,7 +67,7 @@ static inline void no_context(struct pt_regs *regs, unsigned long addr)
 	pr_alert("Unable to handle kernel paging request at virtual "
 		 "addr 0x%08lx, pc: 0x%08lx\n", addr, regs->pc);
 	die(regs, "Oops");
-	do_exit(SIGKILL);
+	make_task_dead(SIGKILL);
 }
 
 static inline void mm_fault_error(struct pt_regs *regs, unsigned long addr, vm_fault_t fault)

diff --git a/arch/h8300/kernel/traps.c b/arch/h8300/kernel/traps.c
index bdbe988d8dbc..3d4e0bde37ae 100644
--- a/arch/h8300/kernel/traps.c
+++ b/arch/h8300/kernel/traps.c

@@ -106,7 +106,7 @@ void die(const char *str, struct pt_regs *fp, unsigned long err)
 	dump(fp);
 
 	spin_unlock_irq(&die_lock);
-	do_exit(SIGSEGV);
+	make_dead_task(SIGSEGV);
 }
 
 static int kstack_depth_to_print = 24;

diff --git a/arch/h8300/mm/fault.c b/arch/h8300/mm/fault.c
index d4bc9c16f2df..0223528565dd 100644
--- a/arch/h8300/mm/fault.c
+++ b/arch/h8300/mm/fault.c

@@ -51,7 +51,7 @@ asmlinkage int do_page_fault(struct pt_regs *regs, unsigned long address,
 	printk(" at virtual address %08lx\n", address);
 	if (!user_mode(regs))
 		die("Oops", regs, error_code);
-	do_exit(SIGKILL);
+	make_dead_task(SIGKILL);
 
 	return 1;
 }

diff --git a/arch/hexagon/kernel/traps.c b/arch/hexagon/kernel/traps.c
index edfc35dafeb1..6dd6cf0ab711 100644
--- a/arch/hexagon/kernel/traps.c
+++ b/arch/hexagon/kernel/traps.c

@@ -214,7 +214,7 @@ int die(const char *str, struct pt_regs *regs, long err)
 		panic("Fatal exception");
 
 	oops_exit();
-	do_exit(err);
+	make_dead_task(err);
 	return 0;
 }

diff --git a/arch/ia64/kernel/mca_drv.c b/arch/ia64/kernel/mca_drv.c
index 5bfc79be4cef..23c203639a96 100644
--- a/arch/ia64/kernel/mca_drv.c
+++ b/arch/ia64/kernel/mca_drv.c

@@ -176,7 +176,7 @@ mca_handler_bh(unsigned long paddr, void *iip, unsigned long ipsr)
 	spin_unlock(&mca_bh_lock);
 
 	/* This process is about to be killed itself */
-	do_exit(SIGKILL);
+	make_task_dead(SIGKILL);
 }
 
 /**

diff --git a/arch/ia64/kernel/traps.c b/arch/ia64/kernel/traps.c
index e13cb905930f..753642366e12 100644
--- a/arch/ia64/kernel/traps.c
+++ b/arch/ia64/kernel/traps.c

@@ -85,7 +85,7 @@ die (const char *str, struct pt_regs *regs, long err)
 	if (panic_on_oops)
 		panic("Fatal exception");
 
-  	do_exit(SIGSEGV);
+	make_task_dead(SIGSEGV);
 	return 0;
 }

diff --git a/arch/ia64/mm/fault.c b/arch/ia64/mm/fault.c
index 02de2e70c587..4796cccbf74f 100644
--- a/arch/ia64/mm/fault.c
+++ b/arch/ia64/mm/fault.c

@@ -259,7 +259,7 @@ ia64_do_page_fault (unsigned long address, unsigned long isr, struct pt_regs *re
 		regs = NULL;
 	bust_spinlocks(0);
 	if (regs)
-		do_exit(SIGKILL);
+		make_task_dead(SIGKILL);
 	return;
 
   out_of_memory:

diff --git a/arch/m68k/kernel/traps.c b/arch/m68k/kernel/traps.c
index 34d6458340b0..59fc63feb0dc 100644
--- a/arch/m68k/kernel/traps.c
+++ b/arch/m68k/kernel/traps.c

@@ -1131,7 +1131,7 @@ void die_if_kernel (char *str, struct pt_regs *fp, int nr)
 	pr_crit("%s: %08x\n", str, nr);
 	show_registers(fp);
 	add_taint(TAINT_DIE, LOCKDEP_NOW_UNRELIABLE);
-	do_exit(SIGSEGV);
+	make_task_dead(SIGSEGV);
 }
 
 asmlinkage void set_esp0(unsigned long ssp)

diff --git a/arch/m68k/mm/fault.c b/arch/m68k/mm/fault.c
index ef46e77e97a5..fcb3a0d8421c 100644
--- a/arch/m68k/mm/fault.c
+++ b/arch/m68k/mm/fault.c

@@ -48,7 +48,7 @@ int send_fault_sig(struct pt_regs *regs)
 			pr_alert("Unable to handle kernel access");
 		pr_cont(" at virtual address %p\n", addr);
 		die_if_kernel("Oops", regs, 0 /*error_code*/);
-		do_exit(SIGKILL);
+		make_task_dead(SIGKILL);
 	}
 
 	return 1;

diff --git a/arch/microblaze/kernel/exceptions.c b/arch/microblaze/kernel/exceptions.c
index 908788497b28..fd153d5fab98 100644
--- a/arch/microblaze/kernel/exceptions.c
+++ b/arch/microblaze/kernel/exceptions.c

@@ -44,10 +44,10 @@ void die(const char *str, struct pt_regs *fp, long err)
 	pr_warn("Oops: %s, sig: %ld\n", str, err);
 	show_regs(fp);
 	spin_unlock_irq(&die_lock);
-	/* do_exit() should take care of panic'ing from an interrupt
+	/* make_task_dead() should take care of panic'ing from an interrupt
 	 * context so we don't handle it here
 	 */
-	do_exit(err);
+	make_task_dead(err);
 }
 
 /* for user application debugging */

diff --git a/arch/mips/kernel/traps.c b/arch/mips/kernel/traps.c
index d26b0fb8ea06..a486486b2355 100644
--- a/arch/mips/kernel/traps.c
+++ b/arch/mips/kernel/traps.c

@@ -422,7 +422,7 @@ void __noreturn die(const char *str, struct pt_regs *regs)
 	if (regs && kexec_should_crash(current))
 		crash_kexec(regs);
 
-	do_exit(sig);
+	make_task_dead(sig);
 }
 
 extern struct exception_table_entry __start___dbe_table[];

diff --git a/arch/nds32/kernel/fpu.c b/arch/nds32/kernel/fpu.c
index 9edd7ed7d7bf..701c09a668de 100644
--- a/arch/nds32/kernel/fpu.c
+++ b/arch/nds32/kernel/fpu.c

@@ -223,7 +223,7 @@ inline void handle_fpu_exception(struct pt_regs *regs)
 		}
 	} else if (fpcsr & FPCSR_mskRIT) {
 		if (!user_mode(regs))
-			do_exit(SIGILL);
+			make_task_dead(SIGILL);
 		si_signo = SIGILL;
 	}

diff --git a/arch/nds32/kernel/traps.c b/arch/nds32/kernel/traps.c
index ca75d475eda4..c0a8f3344fb9 100644
--- a/arch/nds32/kernel/traps.c
+++ b/arch/nds32/kernel/traps.c

@@ -141,7 +141,7 @@ void __noreturn die(const char *str, struct pt_regs *regs, int err)
 
 	bust_spinlocks(0);
 	spin_unlock_irq(&die_lock);
-	do_exit(SIGSEGV);
+	make_task_dead(SIGSEGV);
 }
 
 EXPORT_SYMBOL(die);

@@ -240,7 +240,7 @@ void unhandled_interruption(struct pt_regs *regs)
 	pr_emerg("unhandled_interruption\n");
 	show_regs(regs);
 	if (!user_mode(regs))
-		do_exit(SIGKILL);
+		make_task_dead(SIGKILL);
 	force_sig(SIGKILL);
 }

@@ -251,7 +251,7 @@ void unhandled_exceptions(unsigned long entry, unsigned long addr,
 		 addr, type);
 	show_regs(regs);
 	if (!user_mode(regs))
-		do_exit(SIGKILL);
+		make_task_dead(SIGKILL);
 	force_sig(SIGKILL);
 }

@@ -278,7 +278,7 @@ void do_revinsn(struct pt_regs *regs)
 	pr_emerg("Reserved Instruction\n");
 	show_regs(regs);
 	if (!user_mode(regs))
-		do_exit(SIGILL);
+		make_task_dead(SIGILL);
 	force_sig(SIGILL);
 }

diff --git a/arch/nios2/kernel/traps.c b/arch/nios2/kernel/traps.c
index 596986a74a26..85ac49d64cf7 100644
--- a/arch/nios2/kernel/traps.c
+++ b/arch/nios2/kernel/traps.c

@@ -37,10 +37,10 @@ void die(const char *str, struct pt_regs *regs, long err)
 	show_regs(regs);
 	spin_unlock_irq(&die_lock);
 	/*
-	 * do_exit() should take care of panic'ing from an interrupt
+	 * make_task_dead() should take care of panic'ing from an interrupt
 	 * context so we don't handle it here
 	 */
-	do_exit(err);
+	make_task_dead(err);
 }
 
 void _exception(int signo, struct pt_regs *regs, int code, unsigned long addr)

diff --git a/arch/openrisc/kernel/traps.c b/arch/openrisc/kernel/traps.c
index 0898cb159fac..0446a3c34372 100644
--- a/arch/openrisc/kernel/traps.c
+++ b/arch/openrisc/kernel/traps.c

@@ -212,7 +212,7 @@ void __noreturn die(const char *str, struct pt_regs *regs, long err)
 	__asm__ __volatile__("l.nop   1");
 	do {} while (1);
 #endif
-	do_exit(SIGSEGV);
+	make_task_dead(SIGSEGV);
 }
 
 /* This is normally the 'Oops' routine */

diff --git a/arch/parisc/kernel/traps.c b/arch/parisc/kernel/traps.c
index b11fb26ce299..df2122c50d78 100644
--- a/arch/parisc/kernel/traps.c
+++ b/arch/parisc/kernel/traps.c

@@ -269,7 +269,7 @@ void die_if_kernel(char *str, struct pt_regs *regs, long err)
 		panic("Fatal exception");
 
 	oops_exit();
-	do_exit(SIGSEGV);
+	make_task_dead(SIGSEGV);
 }
 
 /* gdb uses break 4,8 */

diff --git a/arch/powerpc/kernel/traps.c b/arch/powerpc/kernel/traps.c
index 11741703d26e..a08bb7cefdc5 100644
--- a/arch/powerpc/kernel/traps.c
+++ b/arch/powerpc/kernel/traps.c

@@ -245,7 +245,7 @@ static void oops_end(unsigned long flags, struct pt_regs *regs,
 
 	if (panic_on_oops)
 		panic("Fatal exception");
-	do_exit(signr);
+	make_task_dead(signr);
 }
 NOKPROBE_SYMBOL(oops_end);

@@ -792,9 +792,9 @@ int machine_check_generic(struct pt_regs *regs)
 void die_mce(const char *str, struct pt_regs *regs, long err)
 {
 	/*
-	 * The machine check wants to kill the interrupted context, but
-	 * do_exit() checks for in_interrupt() and panics in that case, so
-	 * exit the irq/nmi before calling die.
+	 * The machine check wants to kill the interrupted context,
+	 * but make_task_dead() checks for in_interrupt() and panics
+	 * in that case, so exit the irq/nmi before calling die.
 	 */
 	if (in_nmi())
 		nmi_exit();

diff --git a/arch/riscv/kernel/traps.c b/arch/riscv/kernel/traps.c
index 0daaa3e4630d..fe92e119e6a3 100644
--- a/arch/riscv/kernel/traps.c
+++ b/arch/riscv/kernel/traps.c

@@ -54,7 +54,7 @@ void die(struct pt_regs *regs, const char *str)
 	if (panic_on_oops)
 		panic("Fatal exception");
 	if (ret != NOTIFY_STOP)
-		do_exit(SIGSEGV);
+		make_task_dead(SIGSEGV);
 }
 
 void do_trap(struct pt_regs *regs, int signo, int code, unsigned long addr)

diff --git a/arch/riscv/mm/fault.c b/arch/riscv/mm/fault.c
index aa08dd2f8fae..42118bc728f9 100644
--- a/arch/riscv/mm/fault.c
+++ b/arch/riscv/mm/fault.c

@@ -31,7 +31,7 @@ static void die_kernel_fault(const char *msg, unsigned long addr,
 
 	bust_spinlocks(0);
 	die(regs, "Oops");
-	do_exit(SIGKILL);
+	make_task_dead(SIGKILL);
 }
 
 static inline void no_context(struct pt_regs *regs, unsigned long addr)

diff --git a/arch/s390/kernel/dumpstack.c b/arch/s390/kernel/dumpstack.c
index 0681c55e831d..1e3233eb510a 100644
--- a/arch/s390/kernel/dumpstack.c
+++ b/arch/s390/kernel/dumpstack.c

@@ -224,5 +224,5 @@ void __noreturn die(struct pt_regs *regs, const char *str)
 	if (panic_on_oops)
 		panic("Fatal exception: panic_on_oops");
 	oops_exit();
-	do_exit(SIGSEGV);
+	make_task_dead(SIGSEGV);
 }

diff --git a/arch/s390/kernel/nmi.c b/arch/s390/kernel/nmi.c
index 20f8e1868853..a4d8c058dd27 100644
--- a/arch/s390/kernel/nmi.c
+++ b/arch/s390/kernel/nmi.c

@@ -175,7 +175,7 @@ void __s390_handle_mcck(void)
 		       "malfunction (code 0x%016lx).\n", mcck.mcck_code);
 		printk(KERN_EMERG "mcck: task: %s, pid: %d.\n",
 		       current->comm, current->pid);
-		do_exit(SIGSEGV);
+		make_task_dead(SIGSEGV);
 	}
 }

diff --git a/arch/sh/kernel/traps.c b/arch/sh/kernel/traps.c
index cbe3201d4f21..01884054aeb2 100644
--- a/arch/sh/kernel/traps.c
+++ b/arch/sh/kernel/traps.c

@@ -57,7 +57,7 @@ void __noreturn die(const char *str, struct pt_regs *regs, long err)
 	if (panic_on_oops)
 		panic("Fatal exception");
 
-	do_exit(SIGSEGV);
+	make_task_dead(SIGSEGV);
 }
 
 void die_if_kernel(const char *str, struct pt_regs *regs, long err)

diff --git a/arch/sparc/kernel/traps_32.c b/arch/sparc/kernel/traps_32.c
index 5630e5a395e0..179aabfa712e 100644
--- a/arch/sparc/kernel/traps_32.c
+++ b/arch/sparc/kernel/traps_32.c

@@ -86,9 +86,7 @@ void __noreturn die_if_kernel(char *str, struct pt_regs *regs)
 	}
 	printk("Instruction DUMP:");
 	instruction_dump ((unsigned long *) regs->pc);
-	if(regs->psr & PSR_PS)
-		do_exit(SIGKILL);
-	do_exit(SIGSEGV);
+	make_task_dead((regs->psr & PSR_PS) ? SIGKILL : SIGSEGV);
 }
 
 void do_hw_interrupt(struct pt_regs *regs, unsigned long type)

diff --git a/arch/sparc/kernel/traps_64.c b/arch/sparc/kernel/traps_64.c
index 6863025ed56d..21077821f427 100644
--- a/arch/sparc/kernel/traps_64.c
+++ b/arch/sparc/kernel/traps_64.c

@@ -2559,9 +2559,7 @@ void __noreturn die_if_kernel(char *str, struct pt_regs *regs)
 	}
 	if (panic_on_oops)
 		panic("Fatal exception");
-	if (regs->tstate & TSTATE_PRIV)
-		do_exit(SIGKILL);
-	do_exit(SIGSEGV);
+	make_task_dead((regs->tstate & TSTATE_PRIV)? SIGKILL : SIGSEGV);
 }
 EXPORT_SYMBOL(die_if_kernel);

diff --git a/arch/x86/entry/entry_32.S b/arch/x86/entry/entry_32.S
index ccb9d32768f3..7738fad6a85e 100644
--- a/arch/x86/entry/entry_32.S
+++ b/arch/x86/entry/entry_32.S

@@ -1248,14 +1248,14 @@ SYM_CODE_START(asm_exc_nmi)
 SYM_CODE_END(asm_exc_nmi)
 
 .pushsection .text, "ax"
-SYM_CODE_START(rewind_stack_do_exit)
+SYM_CODE_START(rewind_stack_and_make_dead)
 	/* Prevent any naive code from trying to unwind to our caller. */
 	xorl	%ebp, %ebp
 
 	movl	PER_CPU_VAR(cpu_current_top_of_stack), %esi
 	leal	-TOP_OF_KERNEL_STACK_PADDING-PTREGS_SIZE(%esi), %esp
 
-	call	do_exit
+	call	make_task_dead
 1:	jmp 1b
-SYM_CODE_END(rewind_stack_do_exit)
+SYM_CODE_END(rewind_stack_and_make_dead)
 .popsection

diff --git a/arch/x86/entry/entry_64.S b/arch/x86/entry/entry_64.S
index e38a4cf795d9..f09276457942 100644
--- a/arch/x86/entry/entry_64.S
+++ b/arch/x86/entry/entry_64.S

@@ -1429,7 +1429,7 @@ SYM_CODE_END(ignore_sysret)
 #endif
 
 .pushsection .text, "ax"
-SYM_CODE_START(rewind_stack_do_exit)
+SYM_CODE_START(rewind_stack_and_make_dead)
 	UNWIND_HINT_FUNC
 	/* Prevent any naive code from trying to unwind to our caller. */
 	xorl	%ebp, %ebp

@@ -1438,6 +1438,6 @@ SYM_CODE_START(rewind_stack_do_exit)
 	leaq	-PTREGS_SIZE(%rax), %rsp
 	UNWIND_HINT_REGS
 
-	call	do_exit
-SYM_CODE_END(rewind_stack_do_exit)
+	call	make_task_dead
+SYM_CODE_END(rewind_stack_and_make_dead)
 .popsection

diff --git a/arch/x86/kernel/dumpstack.c b/arch/x86/kernel/dumpstack.c
index ea4fe192189d..53de044e5654 100644
--- a/arch/x86/kernel/dumpstack.c
+++ b/arch/x86/kernel/dumpstack.c

@@ -351,7 +351,7 @@ unsigned long oops_begin(void)
 }
 NOKPROBE_SYMBOL(oops_begin);
 
-void __noreturn rewind_stack_do_exit(int signr);
+void __noreturn rewind_stack_and_make_dead(int signr);
 
 void oops_end(unsigned long flags, struct pt_regs *regs, int signr)
 {

@@ -386,7 +386,7 @@ void oops_end(unsigned long flags, struct pt_regs *regs, int signr)
 	 * reuse the task stack and that existing poisons are invalid.
 	 */
 	kasan_unpoison_task_stack(current);
-	rewind_stack_do_exit(signr);
+	rewind_stack_and_make_dead(signr);
 }
 NOKPROBE_SYMBOL(oops_end);

diff --git a/arch/xtensa/kernel/traps.c b/arch/xtensa/kernel/traps.c
index 4b4dbeb2d612..9345007d474d 100644
--- a/arch/xtensa/kernel/traps.c
+++ b/arch/xtensa/kernel/traps.c

@@ -552,5 +552,5 @@ void __noreturn die(const char * str, struct pt_regs * regs, long err)
 	if (panic_on_oops)
 		panic("Fatal exception");
 
-	do_exit(err);
+	make_task_dead(err);
 }

diff --git a/include/linux/sched/task.h b/include/linux/sched/task.h
index ba88a6987400..2d4bbd9c3278 100644
--- a/include/linux/sched/task.h
+++ b/include/linux/sched/task.h

@@ -59,6 +59,7 @@ extern void sched_post_fork(struct task_struct *p,
 extern void sched_dead(struct task_struct *p);
 
 void __noreturn do_task_dead(void);
+void __noreturn make_task_dead(int signr);
 
 extern void proc_caches_init(void);

diff --git a/kernel/exit.c b/kernel/exit.c
index f702a6a63686..bfa513c5b227 100644
--- a/kernel/exit.c
+++ b/kernel/exit.c

@@ -884,6 +884,15 @@ void __noreturn do_exit(long code)
 }
 EXPORT_SYMBOL_GPL(do_exit);
 
+void __noreturn make_task_dead(int signr)
+{
+	/*
+	 * Take the task off the cpu after something catastrophic has
+	 * happened.
+	 */
+	do_exit(signr);
+}
+
 void complete_and_exit(struct completion *comp, long code)
 {
 	if (comp)

diff --git a/tools/objtool/check.c b/tools/objtool/check.c
index 21735829b860..e6ab5687770b 100644
--- a/tools/objtool/check.c
+++ b/tools/objtool/check.c

@@ -168,6 +168,7 @@ static bool __dead_end_function(struct objtool_file *file, struct symbol *func,
 		"panic",
 		"do_exit",
 		"do_task_dead",
+		"make_task_dead",
 		"__module_put_and_exit",
 		"complete_and_exit",
 		"__reiserfs_panic",

@@ -175,7 +176,7 @@ static bool __dead_end_function(struct objtool_file *file, struct symbol *func,
 		"fortify_panic",
 		"usercopy_abort",
 		"machine_real_restart",
-		"rewind_stack_do_exit",
+		"rewind_stack_and_make_dead"
 		"kunit_try_catch_throw",
 		"xen_start_kernel",
 		"cpu_bringup_and_idle",

-- 
2.29.2

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