Commit 3fb4f979 authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge tag 's390-5.12-6' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux 

Pull s390 fixes from Heiko Carstens:

 - fix incorrect dereference of the ext_params2 external interrupt
   parameter, which leads to an instant kernel crash if a pfault
   interrupt occurs.

 - add forgotten stack unwinder support, and fix memory leak for the
   new machine check handler stack.

 - fix inline assembly register clobbering due to KASAN code
   instrumentation.

* tag 's390-5.12-6' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
  s390/setup: use memblock_free_late() to free old stack
  s390/irq: fix reading of ext_params2 field from lowcore
  s390/unwind: add machine check handler stack
  s390/cpcmd: fix inline assembly register clobbering
parents e0a472ff ad31a8c0

arch/s390/include/asm/stacktrace.h

+1 −0
Original line number Diff line number Diff line
@@ -12,6 +12,7 @@ enum stack_type { 
	STACK_TYPE_IRQ,

	STACK_TYPE_NODAT,

	STACK_TYPE_RESTART,

	STACK_TYPE_MCCK,

};



struct stack_info {

arch/s390/kernel/cpcmd.c

+4 −2
Original line number Diff line number Diff line
@@ -37,10 +37,12 @@ static int diag8_noresponse(int cmdlen) 


static int diag8_response(int cmdlen, char *response, int *rlen)

{

	unsigned long _cmdlen = cmdlen | 0x40000000L;

	unsigned long _rlen = *rlen;

	register unsigned long reg2 asm ("2") = (addr_t) cpcmd_buf;

	register unsigned long reg3 asm ("3") = (addr_t) response;

	register unsigned long reg4 asm ("4") = cmdlen | 0x40000000L;

	register unsigned long reg5 asm ("5") = *rlen;

	register unsigned long reg4 asm ("4") = _cmdlen;

	register unsigned long reg5 asm ("5") = _rlen;



	asm volatile(

		"	diag	%2,%0,0x8\n"

arch/s390/kernel/dumpstack.c

+11 −1
Original line number Diff line number Diff line
@@ -79,6 +79,15 @@ static bool in_nodat_stack(unsigned long sp, struct stack_info *info) 
	return in_stack(sp, info, STACK_TYPE_NODAT, top - THREAD_SIZE, top);

}



static bool in_mcck_stack(unsigned long sp, struct stack_info *info)

{

	unsigned long frame_size, top;



	frame_size = STACK_FRAME_OVERHEAD + sizeof(struct pt_regs);

	top = S390_lowcore.mcck_stack + frame_size;

	return in_stack(sp, info, STACK_TYPE_MCCK, top - THREAD_SIZE, top);

}



static bool in_restart_stack(unsigned long sp, struct stack_info *info)

{

	unsigned long frame_size, top;
@@ -108,7 +117,8 @@ int get_stack_info(unsigned long sp, struct task_struct *task, 
	/* Check per-cpu stacks */

	if (!in_irq_stack(sp, info) &&

	    !in_nodat_stack(sp, info) &&

	    !in_restart_stack(sp, info))

	    !in_restart_stack(sp, info) &&

	    !in_mcck_stack(sp, info))

		goto unknown;



recursion_check:

arch/s390/kernel/irq.c

+1 −1
Original line number Diff line number Diff line
@@ -174,7 +174,7 @@ void noinstr do_ext_irq(struct pt_regs *regs) 


	memcpy(&regs->int_code, &S390_lowcore.ext_cpu_addr, 4);

	regs->int_parm = S390_lowcore.ext_params;

	regs->int_parm_long = *(unsigned long *)S390_lowcore.ext_params2;

	regs->int_parm_long = S390_lowcore.ext_params2;



	from_idle = !user_mode(regs) && regs->psw.addr == (unsigned long)psw_idle_exit;

	if (from_idle)

arch/s390/kernel/setup.c

+1 −1
Original line number Diff line number Diff line
@@ -354,7 +354,7 @@ static int __init stack_realloc(void) 
	if (!new)

		panic("Couldn't allocate machine check stack");

	WRITE_ONCE(S390_lowcore.mcck_stack, new + STACK_INIT_OFFSET);

	memblock_free(old, THREAD_SIZE);

	memblock_free_late(old, THREAD_SIZE);

	return 0;

}

early_initcall(stack_realloc);