[PATCH] firmware: tegra: reduce stack usage
From: Arnd Bergmann <arnd@kernel.org>
Date: 2020-12-04 19:38:08
Also in:
lkml
Subsystem:
the rest · Maintainer:
Linus Torvalds
From: Arnd Bergmann <arnd@arndb.de>
Building the bpmp-debugfs driver for Arm results in a warning for stack usage:
drivers/firmware/tegra/bpmp-debugfs.c:321:16: error: stack frame size of 1224 bytes in function 'bpmp_debug_store' [-Werror,-Wframe-larger-than=]
static ssize_t bpmp_debug_store(struct file *file, const char __user *buf,
It should be possible to rearrange the code to not require two separate
buffers for the file name, but the easiest workaround is to use dynamic
allocation.
Fixes: 5e37b9c137ee ("firmware: tegra: Add support for in-band debug")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
---
drivers/firmware/tegra/bpmp-debugfs.c | 16 +++++++++++-----
1 file changed, 11 insertions(+), 5 deletions(-)
diff --git a/drivers/firmware/tegra/bpmp-debugfs.c b/drivers/firmware/tegra/bpmp-debugfs.c
index 440d99c63638..e1a6b6add180 100644
--- a/drivers/firmware/tegra/bpmp-debugfs.c
+++ b/drivers/firmware/tegra/bpmp-debugfs.c@@ -74,28 +74,34 @@ static void seqbuf_seek(struct seqbuf *seqbuf, ssize_t offset) static const char *get_filename(struct tegra_bpmp *bpmp, const struct file *file, char *buf, int size) { - char root_path_buf[512]; + char *root_path_buf; const char *root_path; - const char *filename; + const char *filename = NULL; size_t root_len; + root_path_buf = kzalloc(512, GFP_KERNEL); + if (!root_path_buf) + goto out; + root_path = dentry_path(bpmp->debugfs_mirror, root_path_buf, sizeof(root_path_buf)); if (IS_ERR(root_path)) - return NULL; + goto out; root_len = strlen(root_path); filename = dentry_path(file->f_path.dentry, buf, size); if (IS_ERR(filename)) - return NULL; + goto out; if (strlen(filename) < root_len || strncmp(filename, root_path, root_len)) - return NULL; + goto out; filename += root_len; +out: + kfree(root_path_buf); return filename; }
--
2.27.0