From 7b70eb14392a7cf505f9b358d06c33b5af73d1e7 Mon Sep 17 00:00:00 2001
From: Joakim Tjernlund <joakim.tjernlund@infinera.com>
Date: Thu, 1 Mar 2018 14:39:41 +0100
Subject: [PATCH] mtd: cfi: cmdset_0002: Do not allow read/write to suspend erase block.
Git-commit: 7b70eb14392a7cf505f9b358d06c33b5af73d1e7
Patch-mainline: v4.17-rc3
References: bsc#1111666
Currently it is possible to read and/or write to suspend EB's.
Writing /dev/mtdX or /dev/mtdblockX from several processes may
break the flash state machine.
Taken from cfi_cmdset_0001 driver.
Signed-off-by: Joakim Tjernlund <joakim.tjernlund@infinera.com>
Cc: <stable@vger.kernel.org>
Reviewed-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>
Acked-by: Takashi Iwai <tiwai@suse.de>
---
drivers/mtd/chips/cfi_cmdset_0002.c | 9 ++++++---
1 file changed, 6 insertions(+), 3 deletions(-)
diff --git a/drivers/mtd/chips/cfi_cmdset_0002.c b/drivers/mtd/chips/cfi_cmdset_0002.c
index 668e2cbc155b..692902df2598 100644
--- a/drivers/mtd/chips/cfi_cmdset_0002.c
+++ b/drivers/mtd/chips/cfi_cmdset_0002.c
@@ -816,9 +816,10 @@ static int get_chip(struct map_info *map, struct flchip *chip, unsigned long adr
(mode == FL_WRITING && (cfip->EraseSuspend & 0x2))))
goto sleep;
- /* We could check to see if we're trying to access the sector
- * that is currently being erased. However, no user will try
- * anything like that so we just wait for the timeout. */
+ /* Do not allow suspend iff read/write to EB address */
+ if ((adr & chip->in_progress_block_mask) ==
+ chip->in_progress_block_addr)
+ goto sleep;
/* Erase suspend */
/* It's harmless to issue the Erase-Suspend and Erase-Resume
@@ -2267,6 +2268,7 @@ static int __xipram do_erase_chip(struct map_info *map, struct flchip *chip)
chip->state = FL_ERASING;
chip->erase_suspended = 0;
chip->in_progress_block_addr = adr;
+ chip->in_progress_block_mask = ~(map->size - 1);
INVALIDATE_CACHE_UDELAY(map, chip,
adr, map->size,
@@ -2356,6 +2358,7 @@ static int __xipram do_erase_oneblock(struct map_info *map, struct flchip *chip,
chip->state = FL_ERASING;
chip->erase_suspended = 0;
chip->in_progress_block_addr = adr;
+ chip->in_progress_block_mask = ~(len - 1);
INVALIDATE_CACHE_UDELAY(map, chip,
adr, len,
--
2.16.4