[PATCH] net: sfc: avoid format string warning
From: Arnd Bergmann <arnd@kernel.org>
Date: 2026-03-20 15:19:31
Also in:
lkml, llvm
Subsystem:
networking drivers, sfc network driver, the rest · Maintainers:
Andrew Lunn, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Edward Cree, Linus Torvalds
From: Arnd Bergmann <arnd@arndb.de>
Three sfc drivers contain the same *_fill_test() function that takes
a format string argument that gets passed down to snprintf(), producing
a warning with clang-22:
drivers/net/ethernet/sfc/falcon/ethtool.c:227:60: error: diagnostic behavior may be improved by adding
the 'format(printf, 7, 8)' attribute to the declaration of 'ef4_fill_test' [-Werror,-Wmissing-format-attribute]
210 | snprintf(test_str, sizeof(test_str), test_format, test_id);
| ^
drivers/net/ethernet/sfc/falcon/ethtool.c:210:13: note: 'ef4_fill_test' declared here
Rework these to take a varargs based test_format that allows better
type checking and avoids this warning.
Fixes: 3273c2e8c66a ("[netdrvr] sfc: sfc: Add self-test support")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
---
drivers/net/ethernet/sfc/ethtool_common.c | 28 ++++++++++--------
drivers/net/ethernet/sfc/falcon/ethtool.c | 27 ++++++++++-------
.../net/ethernet/sfc/siena/ethtool_common.c | 29 +++++++++++--------
3 files changed, 49 insertions(+), 35 deletions(-)
diff --git a/drivers/net/ethernet/sfc/ethtool_common.c b/drivers/net/ethernet/sfc/ethtool_common.c
index 54f8e4626568..162be23edbe5 100644
--- a/drivers/net/ethernet/sfc/ethtool_common.c
+++ b/drivers/net/ethernet/sfc/ethtool_common.c@@ -254,9 +254,10 @@ int efx_ethtool_set_pauseparam(struct net_device *net_dev, * * Fill in an individual self-test entry. */ -static void efx_fill_test(unsigned int test_index, u8 *strings, u64 *data, - int *test, const char *unit_format, int unit_id, - const char *test_format, const char *test_id) +static void __printf(7, 8) +efx_fill_test(unsigned int test_index, u8 *strings, u64 *data, + int *test, const char *unit_format, int unit_id, + const char *test_format, ...) { char unit_str[ETH_GSTRING_LEN], test_str[ETH_GSTRING_LEN];
@@ -266,12 +267,15 @@ static void efx_fill_test(unsigned int test_index, u8 *strings, u64 *data, /* Fill string, if applicable */ if (strings) { + va_list args; if (strchr(unit_format, '%')) snprintf(unit_str, sizeof(unit_str), unit_format, unit_id); else strcpy(unit_str, unit_format); - snprintf(test_str, sizeof(test_str), test_format, test_id); + va_start(args, test_format); + vsnprintf(test_str, sizeof(test_str), test_format, args); + va_end(args); snprintf(strings + test_index * ETH_GSTRING_LEN, ETH_GSTRING_LEN, "%-6s %-24s", unit_str, test_str);
@@ -349,28 +353,28 @@ int efx_ethtool_fill_self_tests(struct efx_nic *efx, enum efx_loopback_mode mode; efx_fill_test(n++, strings, data, &tests->phy_alive, - "phy", 0, "alive", NULL); + "phy", 0, "alive"); efx_fill_test(n++, strings, data, &tests->nvram, - "core", 0, "nvram", NULL); + "core", 0, "nvram"); efx_fill_test(n++, strings, data, &tests->interrupt, - "core", 0, "interrupt", NULL); + "core", 0, "interrupt"); /* Event queues */ efx_for_each_channel(channel, efx) { efx_fill_test(n++, strings, data, &tests->eventq_dma[channel->channel], EFX_CHANNEL_NAME(channel), - "eventq.dma", NULL); + "eventq.dma"); efx_fill_test(n++, strings, data, &tests->eventq_int[channel->channel], EFX_CHANNEL_NAME(channel), - "eventq.int", NULL); + "eventq.int"); } efx_fill_test(n++, strings, data, &tests->memory, - "core", 0, "memory", NULL); + "core", 0, "memory"); efx_fill_test(n++, strings, data, &tests->registers, - "core", 0, "registers", NULL); + "core", 0, "registers"); for (i = 0; true; ++i) { const char *name;
@@ -380,7 +384,7 @@ int efx_ethtool_fill_self_tests(struct efx_nic *efx, if (name == NULL) break; - efx_fill_test(n++, strings, data, &tests->phy_ext[i], "phy", 0, name, NULL); + efx_fill_test(n++, strings, data, &tests->phy_ext[i], "phy", 0, "%s", name); } /* Loopback tests */
diff --git a/drivers/net/ethernet/sfc/falcon/ethtool.c b/drivers/net/ethernet/sfc/falcon/ethtool.c
index 807c587eba3b..1ae8acb8fdc8 100644
--- a/drivers/net/ethernet/sfc/falcon/ethtool.c
+++ b/drivers/net/ethernet/sfc/falcon/ethtool.c@@ -207,9 +207,10 @@ static void ef4_ethtool_set_msglevel(struct net_device *net_dev, u32 msg_enable) * * Fill in an individual self-test entry. */ -static void ef4_fill_test(unsigned int test_index, u8 *strings, u64 *data, +static void __printf(7, 8) + ef4_fill_test(unsigned int test_index, u8 *strings, u64 *data, int *test, const char *unit_format, int unit_id, - const char *test_format, const char *test_id) + const char *test_format, ...) { char unit_str[ETH_GSTRING_LEN], test_str[ETH_GSTRING_LEN];
@@ -219,12 +220,16 @@ static void ef4_fill_test(unsigned int test_index, u8 *strings, u64 *data, /* Fill string, if applicable */ if (strings) { + va_list arg; + if (strchr(unit_format, '%')) snprintf(unit_str, sizeof(unit_str), unit_format, unit_id); else strcpy(unit_str, unit_format); - snprintf(test_str, sizeof(test_str), test_format, test_id); + va_start(arg, test_format); + vsnprintf(test_str, sizeof(test_str), test_format, arg); + va_end(arg); snprintf(strings + test_index * ETH_GSTRING_LEN, ETH_GSTRING_LEN, "%-6s %-24s", unit_str, test_str);
@@ -303,28 +308,28 @@ static int ef4_ethtool_fill_self_tests(struct ef4_nic *efx, enum ef4_loopback_mode mode; ef4_fill_test(n++, strings, data, &tests->phy_alive, - "phy", 0, "alive", NULL); + "phy", 0, "alive"); ef4_fill_test(n++, strings, data, &tests->nvram, - "core", 0, "nvram", NULL); + "core", 0, "nvram"); ef4_fill_test(n++, strings, data, &tests->interrupt, - "core", 0, "interrupt", NULL); + "core", 0, "interrupt"); /* Event queues */ ef4_for_each_channel(channel, efx) { ef4_fill_test(n++, strings, data, &tests->eventq_dma[channel->channel], EF4_CHANNEL_NAME(channel), - "eventq.dma", NULL); + "eventq.dma"); ef4_fill_test(n++, strings, data, &tests->eventq_int[channel->channel], EF4_CHANNEL_NAME(channel), - "eventq.int", NULL); + "eventq.int"); } ef4_fill_test(n++, strings, data, &tests->memory, - "core", 0, "memory", NULL); + "core", 0, "memory"); ef4_fill_test(n++, strings, data, &tests->registers, - "core", 0, "registers", NULL); + "core", 0, "registers"); if (efx->phy_op->run_tests != NULL) { EF4_BUG_ON_PARANOID(efx->phy_op->test_name == NULL);
@@ -338,7 +343,7 @@ static int ef4_ethtool_fill_self_tests(struct ef4_nic *efx, break; ef4_fill_test(n++, strings, data, &tests->phy_ext[i], - "phy", 0, name, NULL); + "phy", 0, "%s", name); } }
diff --git a/drivers/net/ethernet/sfc/siena/ethtool_common.c b/drivers/net/ethernet/sfc/siena/ethtool_common.c
index 76cbce2b9592..9a8e39c5a113 100644
--- a/drivers/net/ethernet/sfc/siena/ethtool_common.c
+++ b/drivers/net/ethernet/sfc/siena/ethtool_common.c@@ -206,9 +206,9 @@ int efx_siena_ethtool_set_pauseparam(struct net_device *net_dev, * * Fill in an individual self-test entry. */ -static void efx_fill_test(unsigned int test_index, u8 *strings, u64 *data, - int *test, const char *unit_format, int unit_id, - const char *test_format, const char *test_id) +static void __printf(7, 8) +efx_fill_test(unsigned int test_index, u8 *strings, u64 *data, int *test, + const char *unit_format, int unit_id, const char *test_format, ...) { char unit_str[ETH_GSTRING_LEN], test_str[ETH_GSTRING_LEN];
@@ -218,12 +218,16 @@ static void efx_fill_test(unsigned int test_index, u8 *strings, u64 *data, /* Fill string, if applicable */ if (strings) { + va_list args; + if (strchr(unit_format, '%')) snprintf(unit_str, sizeof(unit_str), unit_format, unit_id); else strcpy(unit_str, unit_format); - snprintf(test_str, sizeof(test_str), test_format, test_id); + va_start(args, test_format); + vsnprintf(test_str, sizeof(test_str), test_format, args); + va_end(args); snprintf(strings + test_index * ETH_GSTRING_LEN, ETH_GSTRING_LEN, "%-6s %-24s", unit_str, test_str);
@@ -301,28 +305,28 @@ static int efx_ethtool_fill_self_tests(struct efx_nic *efx, enum efx_loopback_mode mode; efx_fill_test(n++, strings, data, &tests->phy_alive, - "phy", 0, "alive", NULL); + "phy", 0, "alive"); efx_fill_test(n++, strings, data, &tests->nvram, - "core", 0, "nvram", NULL); + "core", 0, "nvram"); efx_fill_test(n++, strings, data, &tests->interrupt, - "core", 0, "interrupt", NULL); + "core", 0, "interrupt"); /* Event queues */ efx_for_each_channel(channel, efx) { efx_fill_test(n++, strings, data, &tests->eventq_dma[channel->channel], EFX_CHANNEL_NAME(channel), - "eventq.dma", NULL); + "eventq.dma"); efx_fill_test(n++, strings, data, &tests->eventq_int[channel->channel], EFX_CHANNEL_NAME(channel), - "eventq.int", NULL); + "eventq.int"); } efx_fill_test(n++, strings, data, &tests->memory, - "core", 0, "memory", NULL); + "core", 0, "memory"); efx_fill_test(n++, strings, data, &tests->registers, - "core", 0, "registers", NULL); + "core", 0, "registers"); for (i = 0; true; ++i) { const char *name;
@@ -332,7 +336,8 @@ static int efx_ethtool_fill_self_tests(struct efx_nic *efx, if (name == NULL) break; - efx_fill_test(n++, strings, data, &tests->phy_ext[i], "phy", 0, name, NULL); + efx_fill_test(n++, strings, data, &tests->phy_ext[i], "phy", + 0, "%s", name); } /* Loopback tests */
--
2.39.5