The patch below does not apply to the 5.15-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 925ea0fa5277c1e6bb9e51955ef34eea9736c3d7 Mon Sep 17 00:00:00 2001 From: Tony Lindgren tony@atomide.com Date: Thu, 12 May 2022 16:15:06 +0300 Subject: [PATCH] tty: n_gsm: Fix packet data hex dump output
The module param debug for n_gsm uses KERN_INFO level, but the hexdump now uses KERN_DEBUG level. This started after commit 091cb0994edd ("lib/hexdump: make print_hex_dump_bytes() a nop on !DEBUG builds"). We now use dynamic_hex_dump() unless DEBUG is set.
This causes no packets to be seen with modprobe n_gsm debug=0x1f unlike earlier. Let's fix this by adding gsm_hex_dump_bytes() that calls print_hex_dump() with KERN_INFO to match what n_gsm is doing with the other debug related output.
Fixes: 091cb0994edd ("lib/hexdump: make print_hex_dump_bytes() a nop on !DEBUG builds") Cc: Stephen Boyd swboyd@chromium.org Signed-off-by: Tony Lindgren tony@atomide.com Link: https://lore.kernel.org/r/20220512131506.1216-1-tony@atomide.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
diff --git a/drivers/tty/n_gsm.c b/drivers/tty/n_gsm.c index 8fc05b60ac7f..137eebdcfda9 100644 --- a/drivers/tty/n_gsm.c +++ b/drivers/tty/n_gsm.c @@ -444,6 +444,25 @@ static u8 gsm_encode_modem(const struct gsm_dlci *dlci) return modembits; }
+static void gsm_hex_dump_bytes(const char *fname, const u8 *data, + unsigned long len) +{ + char *prefix; + + if (!fname) { + print_hex_dump(KERN_INFO, "", DUMP_PREFIX_NONE, 16, 1, data, len, + true); + return; + } + + prefix = kasprintf(GFP_KERNEL, "%s: ", fname); + if (!prefix) + return; + print_hex_dump(KERN_INFO, prefix, DUMP_PREFIX_OFFSET, 16, 1, data, len, + true); + kfree(prefix); +} + /** * gsm_print_packet - display a frame for debug * @hdr: header to print before decode @@ -508,7 +527,7 @@ static void gsm_print_packet(const char *hdr, int addr, int cr, else pr_cont("(F)");
- print_hex_dump_bytes("", DUMP_PREFIX_NONE, data, dlen); + gsm_hex_dump_bytes(NULL, data, dlen); }
@@ -698,9 +717,7 @@ static void gsm_data_kick(struct gsm_mux *gsm, struct gsm_dlci *dlci) }
if (debug & 4) - print_hex_dump_bytes("gsm_data_kick: ", - DUMP_PREFIX_OFFSET, - gsm->txframe, len); + gsm_hex_dump_bytes(__func__, gsm->txframe, len); if (gsmld_output(gsm, gsm->txframe, len) <= 0) break; /* FIXME: Can eliminate one SOF in many more cases */ @@ -2444,8 +2461,7 @@ static int gsmld_output(struct gsm_mux *gsm, u8 *data, int len) return -ENOSPC; } if (debug & 4) - print_hex_dump_bytes("gsmld_output: ", DUMP_PREFIX_OFFSET, - data, len); + gsm_hex_dump_bytes(__func__, data, len); return gsm->tty->ops->write(gsm->tty, data, len); }
@@ -2521,8 +2537,7 @@ static void gsmld_receive_buf(struct tty_struct *tty, const unsigned char *cp, char flags = TTY_NORMAL;
if (debug & 4) - print_hex_dump_bytes("gsmld_receive: ", DUMP_PREFIX_OFFSET, - cp, count); + gsm_hex_dump_bytes(__func__, cp, count);
for (; count; count--, cp++) { if (fp)