linux-kernel - [PATCH 15/21] ARM: dma-mapping: always invalidate WT caches before DMA

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Mon, 27 Mar 2023 14:13:11 +0200
From:   Arnd Bergmann <arnd@...nel.org>
To:     linux-kernel@...r.kernel.org
Cc:     Arnd Bergmann <arnd@...db.de>, Vineet Gupta <vgupta@...nel.org>,
        Russell King <linux@...linux.org.uk>,
        Neil Armstrong <neil.armstrong@...aro.org>,
        Linus Walleij <linus.walleij@...aro.org>,
        Catalin Marinas <catalin.marinas@....com>,
        Will Deacon <will@...nel.org>, Guo Ren <guoren@...nel.org>,
        Brian Cain <bcain@...cinc.com>,
        Geert Uytterhoeven <geert@...ux-m68k.org>,
        Michal Simek <monstr@...str.eu>,
        Thomas Bogendoerfer <tsbogend@...ha.franken.de>,
        Dinh Nguyen <dinguyen@...nel.org>,
        Stafford Horne <shorne@...il.com>,
        Helge Deller <deller@....de>,
        Michael Ellerman <mpe@...erman.id.au>,
        Christophe Leroy <christophe.leroy@...roup.eu>,
        Paul Walmsley <paul.walmsley@...ive.com>,
        Palmer Dabbelt <palmer@...belt.com>,
        Rich Felker <dalias@...c.org>,
        John Paul Adrian Glaubitz <glaubitz@...sik.fu-berlin.de>,
        "David S. Miller" <davem@...emloft.net>,
        Max Filippov <jcmvbkbc@...il.com>,
        Christoph Hellwig <hch@....de>,
        Robin Murphy <robin.murphy@....com>,
        Lad Prabhakar <prabhakar.mahadev-lad.rj@...renesas.com>,
        Conor Dooley <conor.dooley@...rochip.com>,
        linux-snps-arc@...ts.infradead.org,
        linux-arm-kernel@...ts.infradead.org, linux-oxnas@...ups.io,
        linux-csky@...r.kernel.org, linux-hexagon@...r.kernel.org,
        linux-m68k@...ts.linux-m68k.org, linux-mips@...r.kernel.org,
        linux-openrisc@...r.kernel.org, linux-parisc@...r.kernel.org,
        linuxppc-dev@...ts.ozlabs.org, linux-riscv@...ts.infradead.org,
        linux-sh@...r.kernel.org, sparclinux@...r.kernel.org,
        linux-xtensa@...ux-xtensa.org
Subject: [PATCH 15/21] ARM: dma-mapping: always invalidate WT caches before DMA

From: Arnd Bergmann <arnd@...db.de>

Most ARM CPUs can have write-back caches and that require
cache management to be done in the dma_sync_*_for_device()
operation. This is typically done in both writeback and
writethrough mode.

The cache-v4.S (arm720/740/7tdmi/9tdmi) and cache-v4wt.S
(arm920t, arm940t) implementations are the exception here,
and only do the cache management after the DMA is complete,
in the dma_sync_*_for_cpu() operation.

Change this for consistency with the other platforms. This
should have no user visible effect.

Signed-off-by: Arnd Bergmann <arnd@...db.de>
---
 arch/arm/mm/cache-v4.S   | 8 ++++----
 arch/arm/mm/cache-v4wt.S | 8 ++++----
 2 files changed, 8 insertions(+), 8 deletions(-)

diff --git a/arch/arm/mm/cache-v4.S b/arch/arm/mm/cache-v4.S
index 7787057e4990..e2b104876340 100644
--- a/arch/arm/mm/cache-v4.S
+++ b/arch/arm/mm/cache-v4.S
@@ -117,23 +117,23 @@ ENTRY(v4_dma_flush_range)
 	ret	lr
 
 /*
- *	dma_unmap_area(start, size, dir)
+ *	dma_map_area(start, size, dir)
  *	- start	- kernel virtual start address
  *	- size	- size of region
  *	- dir	- DMA direction
  */
-ENTRY(v4_dma_unmap_area)
+ENTRY(v4_dma_map_area)
 	teq	r2, #DMA_TO_DEVICE
 	bne	v4_dma_flush_range
 	/* FALLTHROUGH */
 
 /*
- *	dma_map_area(start, size, dir)
+ *	dma_unmap_area(start, size, dir)
  *	- start	- kernel virtual start address
  *	- size	- size of region
  *	- dir	- DMA direction
  */
-ENTRY(v4_dma_map_area)
+ENTRY(v4_dma_unmap_area)
 	ret	lr
 ENDPROC(v4_dma_unmap_area)
 ENDPROC(v4_dma_map_area)
diff --git a/arch/arm/mm/cache-v4wt.S b/arch/arm/mm/cache-v4wt.S
index 0b290c25a99d..652218752f88 100644
--- a/arch/arm/mm/cache-v4wt.S
+++ b/arch/arm/mm/cache-v4wt.S
@@ -172,24 +172,24 @@ v4wt_dma_inv_range:
 	.equ	v4wt_dma_flush_range, v4wt_dma_inv_range
 
 /*
- *	dma_unmap_area(start, size, dir)
+ *	dma_map_area(start, size, dir)
  *	- start	- kernel virtual start address
  *	- size	- size of region
  *	- dir	- DMA direction
  */
-ENTRY(v4wt_dma_unmap_area)
+ENTRY(v4wt_dma_map_area)
 	add	r1, r1, r0
 	teq	r2, #DMA_TO_DEVICE
 	bne	v4wt_dma_inv_range
 	/* FALLTHROUGH */
 
 /*
- *	dma_map_area(start, size, dir)
+ *	dma_unmap_area(start, size, dir)
  *	- start	- kernel virtual start address
  *	- size	- size of region
  *	- dir	- DMA direction
  */
-ENTRY(v4wt_dma_map_area)
+ENTRY(v4wt_dma_unmap_area)
 	ret	lr
 ENDPROC(v4wt_dma_unmap_area)
 ENDPROC(v4wt_dma_map_area)
-- 
2.39.2