linux-kernel - Re: [PATCH v11 2/9] ARM: l2c: use l2c_write_sec() for restoring latency and filter regs

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, 5 Jan 2015 11:20:29 -0600
From:	Nishanth Menon <nm@...com>
To:	Marek Szyprowski <m.szyprowski@...sung.com>
CC:	<linux-kernel@...r.kernel.org>,
	<linux-arm-kernel@...ts.infradead.org>,
	Tomasz Figa <tomasz.figa@...il.com>,
	Kyungmin Park <kyungmin.park@...sung.com>,
	<linux-samsung-soc@...r.kernel.org>, <linux-omap@...r.kernel.org>,
	Arnd Bergmann <arnd@...db.de>, Olof Johansson <olof@...om.net>,
	Russell King - ARM Linux <linux@....linux.org.uk>,
	Kukjin Kim <kgene.kim@...sung.com>, <lauraa@...eaurora.org>,
	<linus.walleij@...aro.org>, <tony@...mide.com>,
	<drake@...lessm.com>, <loeliger@...il.com>,
	Mark Rutland <mark.rutland@....com>, <khilman@...aro.org>
Subject: Re: [PATCH v11 2/9] ARM: l2c: use l2c_write_sec() for restoring
 latency and filter regs

On 13:19-20150105, Marek Szyprowski wrote:
> All four register for latency and filter settings cannot be written in
> non-secure mode and they should go through l2c_write_sec(). More on this
> can be found in CoreLink Level 2 Cache Controller L2C-310 Technical
> Reference Manual, 3.2. Register summary, table 3.1. This have been checked
> the TRM for r3p3, but it should be uniform for all revisions.
> 
> Reported-by: Nishanth Menon <nm@...com>
> Suggested-by: Tomasz Figa <tomasz.figa@...il.com>
> Signed-off-by: Marek Szyprowski <m.szyprowski@...sung.com>
> ---
>  arch/arm/mm/cache-l2x0.c | 16 ++++++++--------
>  1 file changed, 8 insertions(+), 8 deletions(-)
> 
> diff --git a/arch/arm/mm/cache-l2x0.c b/arch/arm/mm/cache-l2x0.c
> index 5e65ca8dea62..0aeeaa95c42d 100644
> --- a/arch/arm/mm/cache-l2x0.c
> +++ b/arch/arm/mm/cache-l2x0.c
> @@ -623,14 +623,14 @@ static void l2c310_resume(void)
>  		unsigned revision;
>  
>  		/* restore pl310 setup */
> -		writel_relaxed(l2x0_saved_regs.tag_latency,
> -			       base + L310_TAG_LATENCY_CTRL);
> -		writel_relaxed(l2x0_saved_regs.data_latency,
> -			       base + L310_DATA_LATENCY_CTRL);
> -		writel_relaxed(l2x0_saved_regs.filter_end,
> -			       base + L310_ADDR_FILTER_END);
> -		writel_relaxed(l2x0_saved_regs.filter_start,
> -			       base + L310_ADDR_FILTER_START);
> +		l2c_write_sec(l2x0_saved_regs.tag_latency, base,
> +			      L310_TAG_LATENCY_CTRL);
> +		l2c_write_sec(l2x0_saved_regs.data_latency, base,
> +			      L310_DATA_LATENCY_CTRL);
> +		l2c_write_sec(l2x0_saved_regs.filter_end, base,
> +			      L310_ADDR_FILTER_END);
> +		l2c_write_sec(l2x0_saved_regs.filter_start, base,
> +			      L310_ADDR_FILTER_START);
>  
>  		revision = readl_relaxed(base + L2X0_CACHE_ID) &
>  				L2X0_CACHE_ID_RTL_MASK;
Do you need the following as well at this point in the patch series?
Agreed that the writes will disappear later in the series.

diff --git a/arch/arm/mm/cache-l2x0.c b/arch/arm/mm/cache-l2x0.c
index 0aeeaa9..7afab37 100644
--- a/arch/arm/mm/cache-l2x0.c
+++ b/arch/arm/mm/cache-l2x0.c
@@ -1135,28 +1135,28 @@ static void __init l2c310_of_parse(const struct device_node *np,
 
 	of_property_read_u32_array(np, "arm,tag-latency", tag, ARRAY_SIZE(tag));
 	if (tag[0] && tag[1] && tag[2])
-		writel_relaxed(
+		l2c_write_sec(
 			L310_LATENCY_CTRL_RD(tag[0] - 1) |
 			L310_LATENCY_CTRL_WR(tag[1] - 1) |
 			L310_LATENCY_CTRL_SETUP(tag[2] - 1),
-			l2x0_base + L310_TAG_LATENCY_CTRL);
+			l2x0_base, L310_TAG_LATENCY_CTRL);
 
 	of_property_read_u32_array(np, "arm,data-latency",
 				   data, ARRAY_SIZE(data));
 	if (data[0] && data[1] && data[2])
-		writel_relaxed(
+		l2c_write_sec(
 			L310_LATENCY_CTRL_RD(data[0] - 1) |
 			L310_LATENCY_CTRL_WR(data[1] - 1) |
 			L310_LATENCY_CTRL_SETUP(data[2] - 1),
-			l2x0_base + L310_DATA_LATENCY_CTRL);
+			l2x0_base,  L310_DATA_LATENCY_CTRL);
 
 	of_property_read_u32_array(np, "arm,filter-ranges",
 				   filter, ARRAY_SIZE(filter));
 	if (filter[1]) {
-		writel_relaxed(ALIGN(filter[0] + filter[1], SZ_1M),
-			       l2x0_base + L310_ADDR_FILTER_END);
-		writel_relaxed((filter[0] & ~(SZ_1M - 1)) | L310_ADDR_FILTER_EN,
-			       l2x0_base + L310_ADDR_FILTER_START);
+		l2c_write_sec(ALIGN(filter[0] + filter[1], SZ_1M),
+			       l2x0_base, L310_ADDR_FILTER_END);
+		l2c_write_sec((filter[0] & ~(SZ_1M - 1)) | L310_ADDR_FILTER_EN,
+			       l2x0_base, L310_ADDR_FILTER_START);
 	}
 
 	ret = l2x0_cache_size_of_parse(np, aux_val, aux_mask, &assoc, SZ_512K);
 
-- 
Regards,
Nishanth Menon
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/