Commit 418b4d5e authored by Vasily Gorbik's avatar Vasily Gorbik Committed by Alexander Gordeev
Browse files

s390/boot: Add vmem debugging support 



Introduce boot_debug() calls in vmem code to log page table mappings
including KASAN shadow mappings for improved early boot debugging.

Signed-off-by: default avatarVasily Gorbik <gor@linux.ibm.com>
Acked-by: default avatarHeiko Carstens <hca@linux.ibm.com>
Signed-off-by: default avatarAlexander Gordeev <agordeev@linux.ibm.com>
parent a56827e5

arch/s390/boot/vmem.c

+44 −3
Original line number Diff line number Diff line 
// SPDX-License-Identifier: GPL-2.0

#define boot_fmt(fmt) "vmem: " fmt

#include <linux/sched/task.h>

#include <linux/pgtable.h>

#include <linux/kasan.h>
@@ -32,12 +33,42 @@ enum populate_mode { 
	POPULATE_IDENTITY,

	POPULATE_KERNEL,

#ifdef CONFIG_KASAN

	/* KASAN modes should be last and grouped together, see is_kasan_populate_mode() */

	POPULATE_KASAN_MAP_SHADOW,

	POPULATE_KASAN_ZERO_SHADOW,

	POPULATE_KASAN_SHALLOW

#endif

};



#define POPULATE_MODE_NAME(t) case POPULATE_ ## t: return #t

static inline const char *get_populate_mode_name(enum populate_mode t)

{

	switch (t) {

	POPULATE_MODE_NAME(NONE);

	POPULATE_MODE_NAME(DIRECT);

	POPULATE_MODE_NAME(LOWCORE);

	POPULATE_MODE_NAME(ABS_LOWCORE);

	POPULATE_MODE_NAME(IDENTITY);

	POPULATE_MODE_NAME(KERNEL);

#ifdef CONFIG_KASAN

	POPULATE_MODE_NAME(KASAN_MAP_SHADOW);

	POPULATE_MODE_NAME(KASAN_ZERO_SHADOW);

	POPULATE_MODE_NAME(KASAN_SHALLOW);

#endif

	default:

		return "UNKNOWN";

	}

}



static bool is_kasan_populate_mode(enum populate_mode mode)

{

#ifdef CONFIG_KASAN

	return mode >= POPULATE_KASAN_MAP_SHADOW;

#else

	return false;

#endif

}



static void pgtable_populate(unsigned long addr, unsigned long end, enum populate_mode mode);



#ifdef CONFIG_KASAN
@@ -53,9 +84,12 @@ static pte_t pte_z; 


static inline void kasan_populate(unsigned long start, unsigned long end, enum populate_mode mode)

{

	start = PAGE_ALIGN_DOWN(__sha(start));

	end = PAGE_ALIGN(__sha(end));

	pgtable_populate(start, end, mode);

	unsigned long sha_start = PAGE_ALIGN_DOWN(__sha(start));

	unsigned long sha_end = PAGE_ALIGN(__sha(end));



	boot_debug("%-17s 0x%016lx-0x%016lx >> 0x%016lx-0x%016lx\n", get_populate_mode_name(mode),

		   start, end, sha_start, sha_end);

	pgtable_populate(sha_start, sha_end, mode);

}



static void kasan_populate_shadow(unsigned long kernel_start, unsigned long kernel_end)
@@ -418,6 +452,13 @@ static void pgtable_populate(unsigned long addr, unsigned long end, enum populat 
	pgd_t *pgd;

	p4d_t *p4d;



	if (!is_kasan_populate_mode(mode)) {

		boot_debug("%-17s 0x%016lx-0x%016lx -> 0x%016lx-0x%016lx\n",

			   get_populate_mode_name(mode), addr, end,

			   resolve_pa_may_alloc(addr, 0, mode),

			   resolve_pa_may_alloc(end - 1, 0, mode) + 1);

	}



	pgd = pgd_offset(&init_mm, addr);

	for (; addr < end; addr = next, pgd++) {

		next = pgd_addr_end(addr, end);