linux-kernel - [PATCH 02/11] clk: tegra: bpmp: Convert to printbuf

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]

Message-Id: <20220815172613.621627-3-kent.overstreet@linux.dev>
Date:   Mon, 15 Aug 2022 13:26:04 -0400
From:   Kent Overstreet <kent.overstreet@...ux.dev>
To:     akpm@...ux-foundation.org
Cc:     linux-kernel@...r.kernel.org,
        Kent Overstreet <kent.overstreet@...il.com>,
        linux-tegra@...r.kernel.org
Subject: [PATCH 02/11] clk: tegra: bpmp: Convert to printbuf

From: Kent Overstreet <kent.overstreet@...il.com>

This converts from seq_buf to printbuf, which is similar but heap
allocates the string buffer.

Previously in this code the string buffer was allocated on the stack;
this means we've added a new potential memory allocation failure. This
is fine though since it's only for a dev_printk() message.

Memory allocation context: printbuf doesn't take gfp flags, instead we
prefer the new memalloc_no*_(save|restore) interfaces to be used. Here
the surrounding code is already allocating with GFP_KERNEL, so
everything is fine.

Signed-off-by: Kent Overstreet <kent.overstreet@...il.com>
Cc: linux-tegra@...r.kernel.org
---
 drivers/clk/tegra/clk-bpmp.c | 21 ++++++++++-----------
 1 file changed, 10 insertions(+), 11 deletions(-)

diff --git a/drivers/clk/tegra/clk-bpmp.c b/drivers/clk/tegra/clk-bpmp.c
index 3748a39dae..7e3b48ed9d 100644
--- a/drivers/clk/tegra/clk-bpmp.c
+++ b/drivers/clk/tegra/clk-bpmp.c
@@ -5,7 +5,7 @@
 
 #include <linux/clk-provider.h>
 #include <linux/device.h>
-#include <linux/seq_buf.h>
+#include <linux/printbuf.h>
 #include <linux/slab.h>
 
 #include <soc/tegra/bpmp.h>
@@ -365,39 +365,38 @@ static void tegra_bpmp_clk_info_dump(struct tegra_bpmp *bpmp,
 				     const struct tegra_bpmp_clk_info *info)
 {
 	const char *prefix = "";
-	struct seq_buf buf;
+	struct printbuf buf = PRINTBUF;
 	unsigned int i;
-	char flags[64];
-
-	seq_buf_init(&buf, flags, sizeof(flags));
 
 	if (info->flags)
-		seq_buf_printf(&buf, "(");
+		prt_printf(&buf, "(");
 
 	if (info->flags & TEGRA_BPMP_CLK_HAS_MUX) {
-		seq_buf_printf(&buf, "%smux", prefix);
+		prt_printf(&buf, "%smux", prefix);
 		prefix = ", ";
 	}
 
 	if ((info->flags & TEGRA_BPMP_CLK_HAS_SET_RATE) == 0) {
-		seq_buf_printf(&buf, "%sfixed", prefix);
+		prt_printf(&buf, "%sfixed", prefix);
 		prefix = ", ";
 	}
 
 	if (info->flags & TEGRA_BPMP_CLK_IS_ROOT) {
-		seq_buf_printf(&buf, "%sroot", prefix);
+		prt_printf(&buf, "%sroot", prefix);
 		prefix = ", ";
 	}
 
 	if (info->flags)
-		seq_buf_printf(&buf, ")");
+		prt_printf(&buf, ")");
 
 	dev_printk(level, bpmp->dev, "%03u: %s\n", info->id, info->name);
-	dev_printk(level, bpmp->dev, "  flags: %lx %s\n", info->flags, flags);
+	dev_printk(level, bpmp->dev, "  flags: %lx %s\n", info->flags, printbuf_str(&buf));
 	dev_printk(level, bpmp->dev, "  parents: %u\n", info->num_parents);
 
 	for (i = 0; i < info->num_parents; i++)
 		dev_printk(level, bpmp->dev, "    %03u\n", info->parents[i]);
+
+	printbuf_exit(&buf);
 }
 
 static int tegra_bpmp_probe_clocks(struct tegra_bpmp *bpmp,
-- 
2.36.1