2022-03-29 09:16:20

by Victor Hassan

[permalink] [raw]
Subject: [RESEND] ARM: mmu: fix access to illegal address when using earlycon & memblock=debug

earlycon uses fixmap to create a memory map,
So we need to close earlycon before closing fixmap,
otherwise printk will access illegal addresses.
After creating a new memory map, we open earlycon again.

Signed-off-by: Victor Hassan <[email protected]>
---
arch/arm/mm/mmu.c | 7 +++++++
1 file changed, 7 insertions(+)

diff --git a/arch/arm/mm/mmu.c b/arch/arm/mm/mmu.c
index 5e2be37a198e..9b8baa222034 100644
--- a/arch/arm/mm/mmu.c
+++ b/arch/arm/mm/mmu.c
@@ -14,6 +14,7 @@
#include <linux/fs.h>
#include <linux/vmalloc.h>
#include <linux/sizes.h>
+#include <linux/console.h>

#include <asm/cp15.h>
#include <asm/cputype.h>
@@ -1697,6 +1698,9 @@ static void __init early_fixmap_shutdown(void)
pmd_clear(fixmap_pmd(va));
local_flush_tlb_kernel_page(va);

+#ifdef CONFIG_FIX_EARLYCON_MEM
+ console_stop(console_drivers);
+#endif
for (i = 0; i < __end_of_permanent_fixed_addresses; i++) {
pte_t *pte;
struct map_desc map;
@@ -1715,6 +1719,9 @@ static void __init early_fixmap_shutdown(void)

create_mapping(&map);
}
+#ifdef CONFIG_FIX_EARLYCON_MEM
+ console_start(console_drivers);
+#endif
}

/*
--
2.29.0