linux_dsm_epyc7002/arch/s390/kernel/early_nobss.c
Martin Schwidefsky 98587c2d89 s390: simplify disabled_wait
The disabled_wait() function uses its argument as the PSW address when
it stops the CPU with a wait PSW that is disabled for interrupts.
The different callers sometimes use a specific number like 0xdeadbeef
to indicate a specific failure, the early boot code uses 0 and some
other calls sites use __builtin_return_address(0).

At the time a dump is created the current PSW and the registers of a
CPU are written to lowcore to make them avaiable to the dump analysis
tool. For a CPU stopped with disabled_wait the PSW and the registers
do not really make sense together, the PSW address does not point to
the function the registers belong to.

Simplify disabled_wait() by using _THIS_IP_ for the PSW address and
drop the argument to the function.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2019-05-02 13:54:11 +02:00

46 lines
1014 B
C

// SPDX-License-Identifier: GPL-2.0
/*
* Copyright IBM Corp. 2007, 2018
*/
/*
* Early setup functions which may not rely on an initialized bss
* section. The last thing that is supposed to happen here is
* initialization of the bss section.
*/
#include <linux/processor.h>
#include <linux/string.h>
#include <asm/sections.h>
#include <asm/lowcore.h>
#include <asm/timex.h>
#include <asm/kasan.h>
#include "entry.h"
static void __init reset_tod_clock(void)
{
u64 time;
if (store_tod_clock(&time) == 0)
return;
/* TOD clock not running. Set the clock to Unix Epoch. */
if (set_tod_clock(TOD_UNIX_EPOCH) != 0 || store_tod_clock(&time) != 0)
disabled_wait();
memset(tod_clock_base, 0, 16);
*(__u64 *) &tod_clock_base[1] = TOD_UNIX_EPOCH;
S390_lowcore.last_update_clock = TOD_UNIX_EPOCH;
}
static void __init clear_bss_section(void)
{
memset(__bss_start, 0, __bss_stop - __bss_start);
}
void __init startup_init_nobss(void)
{
reset_tod_clock();
clear_bss_section();
kasan_early_init();
}