Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
Date:   Thu, 04 Nov 2021 01:37:15 +0100
Message-Id: <990f4427968071d59bcbb7411da73acc379d3ac4.1635986046.git.mirq-linux@rere.qmqm.pl>
From:   =?UTF-8?q?Micha=C5=82=20Miros=C5=82aw?= <mirq-linux@rere.qmqm.pl>
Subject: [PATCH] ARM: fix early early_iounmap()
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
To:     Jon Medhurst <tixy@linaro.org>, Ard Biesheuvel <ardb@kernel.org>,
        Russell King <rmk+kernel@armlinux.org.uk>
Cc:     linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org
Precedence: bulk

Currently __set_fixmap() bails out with a warning when called in early boot
from early_iounmap(). Fix it, and while at it, make the comment a bit easier
to understand.

Cc: <stable@vger.kernel.org>
Fixes: b089c31c519c ("ARM: 8667/3: Fix memory attribute inconsistencies when using fixmap")
Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
---
 arch/arm/mm/mmu.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/arm/mm/mmu.c b/arch/arm/mm/mmu.c
index a4e006005107..274e4f73fd33 100644
--- a/arch/arm/mm/mmu.c
+++ b/arch/arm/mm/mmu.c
@@ -390,9 +390,9 @@ void __set_fixmap(enum fixed_addresses idx, phys_addr_t phys, pgprot_t prot)
 	BUILD_BUG_ON(__fix_to_virt(__end_of_fixed_addresses) < FIXADDR_START);
 	BUG_ON(idx >= __end_of_fixed_addresses);
 
-	/* we only support device mappings until pgprot_kernel has been set */
+	/* We support only device mappings before pgprot_kernel is set. */
 	if (WARN_ON(pgprot_val(prot) != pgprot_val(FIXMAP_PAGE_IO) &&
-		    pgprot_val(pgprot_kernel) == 0))
+		    pgprot_val(prot) && pgprot_val(pgprot_kernel) == 0))
 		return;
 
 	if (pgprot_val(prot))
-- 
2.30.2