2023-02-24 16:22:10

by Martin Povišer

Subject: [PATCH] soc: apple: rtkit: Crop syslog messages

Crop trailing whitespace, null, and newline characters in syslog
messages received from coprocessors. Notably DCP sends its messages
including a trailing newline, so prior to this change we would end up
cluttering the kernel log by repeated newlines at the end of messages.

Signed-off-by: Martin Povišer <[email protected]>
---
drivers/soc/apple/rtkit.c | 14 +++++++++++++-
1 file changed, 13 insertions(+), 1 deletion(-)

diff --git a/drivers/soc/apple/rtkit.c b/drivers/soc/apple/rtkit.c
index 35ec35aa500d..639f5134d159 100644
--- a/drivers/soc/apple/rtkit.c
+++ b/drivers/soc/apple/rtkit.c
@@ -409,11 +409,17 @@ static void apple_rtkit_syslog_rx_init(struct apple_rtkit *rtk, u64 msg)
rtk->syslog_n_entries, rtk->syslog_msg_size);
}

+static bool should_crop_syslog_char(char c)
+{
+ return c == '\n' || c == '\r' || c == ' ' || c == '\0';
+}
+
static void apple_rtkit_syslog_rx_log(struct apple_rtkit *rtk, u64 msg)
{
u8 idx = msg & 0xff;
char log_context[24];
size_t entry_size = 0x20 + rtk->syslog_msg_size;
+ int msglen;

if (!rtk->syslog_msg_buffer) {
dev_warn(
@@ -446,7 +452,13 @@ static void apple_rtkit_syslog_rx_log(struct apple_rtkit *rtk, u64 msg)
rtk->syslog_msg_size);

log_context[sizeof(log_context) - 1] = 0;
- rtk->syslog_msg_buffer[rtk->syslog_msg_size - 1] = 0;
+
+ msglen = rtk->syslog_msg_size - 1;
+ while (msglen > 0 &&
+ should_crop_syslog_char(rtk->syslog_msg_buffer[msglen - 1]))
+ msglen--;
+
+ rtk->syslog_msg_buffer[msglen] = 0;
dev_info(rtk->dev, "RTKit: syslog message: %s: %s\n", log_context,
rtk->syslog_msg_buffer);

--
2.33.0

2023-03-28 11:02:43

by Hector Martin

Subject: Re: [PATCH] soc: apple: rtkit: Crop syslog messages

On 25/02/2023 01.21, Martin Povišer wrote:
> Crop trailing whitespace, null, and newline characters in syslog
> messages received from coprocessors. Notably DCP sends its messages
> including a trailing newline, so prior to this change we would end up
> cluttering the kernel log by repeated newlines at the end of messages.
>
> Signed-off-by: Martin Povišer <[email protected]>
> ---
> drivers/soc/apple/rtkit.c | 14 +++++++++++++-
> 1 file changed, 13 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/soc/apple/rtkit.c b/drivers/soc/apple/rtkit.c
> index 35ec35aa500d..639f5134d159 100644
> --- a/drivers/soc/apple/rtkit.c
> +++ b/drivers/soc/apple/rtkit.c
> @@ -409,11 +409,17 @@ static void apple_rtkit_syslog_rx_init(struct apple_rtkit *rtk, u64 msg)
> rtk->syslog_n_entries, rtk->syslog_msg_size);
> }
>
> +static bool should_crop_syslog_char(char c)
> +{
> + return c == '\n' || c == '\r' || c == ' ' || c == '\0';
> +}
> +
> static void apple_rtkit_syslog_rx_log(struct apple_rtkit *rtk, u64 msg)
> {
> u8 idx = msg & 0xff;
> char log_context[24];
> size_t entry_size = 0x20 + rtk->syslog_msg_size;
> + int msglen;
>
> if (!rtk->syslog_msg_buffer) {
> dev_warn(
> @@ -446,7 +452,13 @@ static void apple_rtkit_syslog_rx_log(struct apple_rtkit *rtk, u64 msg)
> rtk->syslog_msg_size);
>
> log_context[sizeof(log_context) - 1] = 0;
> - rtk->syslog_msg_buffer[rtk->syslog_msg_size - 1] = 0;
> +
> + msglen = rtk->syslog_msg_size - 1;
> + while (msglen > 0 &&
> + should_crop_syslog_char(rtk->syslog_msg_buffer[msglen - 1]))
> + msglen--;
> +
> + rtk->syslog_msg_buffer[msglen] = 0;
> dev_info(rtk->dev, "RTKit: syslog message: %s: %s\n", log_context,
> rtk->syslog_msg_buffer);
>

Reviewed-by: Hector Martin <[email protected]>

Thanks, applied to asahi-soc/soc!

- Hector