The hid-led driver works fine under 4.8.0, however with the next kernel from today I get this: ------------[ cut here ]------------ WARNING: CPU: 0 PID: 2578 at drivers/usb/core/hcd.c:1584 usb_hcd_map_urb_for_dma+0x373/0x550 [usbcore] transfer buffer not dma capable Modules linked in: hid_led(+) usbhid vfat fat ir_sony_decoder iwlmvm led_class mac80211 snd_hda_codec_realtek snd_hda_codec_generic x86_pkg_temp_thermal iwlwifi crc32c_intel snd_hda_codec_hdmi i2c_i801 i2c_smbus snd_hda_intel cfg80211 snd_hda_codec snd_hda_core snd_pcm r8169 snd_timer mei_me mii snd mei ir_lirc_codec lirc_dev nuvoton_cir rc_core btusb btintel bluetooth rfkill usb_storage efivarfs ipv6 ehci_pci ehci_hcd xhci_pci xhci_hcd usbcore usb_common ext4 jbd2 mbcache ahci libahci libata CPU: 0 PID: 2578 Comm: systemd-udevd Not tainted 4.8.0-rc8-next-20161003 #1 Hardware name: ZOTAC ZBOX-CI321NANO/ZBOX-CI321NANO, BIOS B246P105 06/01/2015 ffffc90003dbb7e0 ffffffff81280425 ffffc90003dbb830 0000000000000000 ffffc90003dbb820 ffffffff8105b086 0000063003dbb800 ffff88006f374480 0000000000000000 0000000000000000 0000000000000001 ffff880079544000 Call Trace: [<ffffffff81280425>] dump_stack+0x68/0x93 [<ffffffff8105b086>] __warn+0xc6/0xe0 [<ffffffff8105b0ea>] warn_slowpath_fmt+0x4a/0x50 [<ffffffffa0143a43>] usb_hcd_map_urb_for_dma+0x373/0x550 [usbcore] [<ffffffffa01441b6>] usb_hcd_submit_urb+0x316/0x9c0 [usbcore] [<ffffffff810bce80>] ? rcu_read_lock_sched_held+0x40/0x80 [<ffffffff810e0043>] ? module_assert_mutex_or_preempt+0x13/0x50 [<ffffffff810e0c07>] ? __module_address+0x27/0xf0 [<ffffffffa01456e4>] usb_submit_urb+0x2c4/0x520 [usbcore] [<ffffffffa0145fea>] usb_start_wait_urb+0x5a/0xe0 [usbcore] [<ffffffffa014612c>] usb_control_msg+0xbc/0xf0 [usbcore] [<ffffffff810e0c07>] ? __module_address+0x27/0xf0 [<ffffffffa079a724>] usbhid_raw_request+0xa4/0x180 [usbhid] [<ffffffffa07a93b1>] hidled_recv+0x71/0xe0 [hid_led] [<ffffffffa07a947d>] thingm_init+0x2d/0x50 [hid_led] [<ffffffffa07a969b>] hidled_probe+0xcb/0x24a [hid_led] [<ffffffff814d96f2>] hid_device_probe+0xd2/0x150 [<ffffffff8146023d>] driver_probe_device+0x1fd/0x2c0 [<ffffffff8146039a>] __driver_attach+0x9a/0xa0 [<ffffffff81460300>] ? driver_probe_device+0x2c0/0x2c0 [<ffffffff8145e25d>] bus_for_each_dev+0x5d/0x90 [<ffffffff8145fa79>] driver_attach+0x19/0x20 [<ffffffff8145f5ff>] bus_add_driver+0x11f/0x220 [<ffffffffa07ac000>] ? 0xffffffffa07ac000 [<ffffffff8146086b>] driver_register+0x5b/0xd0 [<ffffffffa07ac000>] ? 0xffffffffa07ac000 [<ffffffff814d83d1>] __hid_register_driver+0x61/0xa0 [<ffffffffa07ac01e>] hidled_driver_init+0x1e/0x20 [hid_led] [<ffffffff81000408>] do_one_initcall+0x38/0x150 [<ffffffff810bce80>] ? rcu_read_lock_sched_held+0x40/0x80 [<ffffffff81194ca0>] ? kmem_cache_alloc_trace+0x1d0/0x230 [<ffffffff811342f9>] do_init_module+0x5a/0x1cb [<ffffffff810e3862>] load_module+0x1e42/0x2530 [<ffffffff810e0990>] ? __symbol_put+0x50/0x50 [<ffffffff810dfc50>] ? show_coresize+0x30/0x30 [<ffffffff811ad650>] ? kernel_read_file+0x100/0x190 [<ffffffff811ad794>] ? kernel_read_file_from_fd+0x44/0x70 [<ffffffff810e415a>] SYSC_finit_module+0xba/0xc0 [<ffffffff810e4179>] SyS_finit_module+0x9/0x10 [<ffffffff815e082a>] entry_SYSCALL_64_fastpath+0x18/0xad ---[ end trace c9e6ea27003ecf9e ]--- Fix this by using a kmalloc'ed buffer when calling hid_hw_raw_request. Signed-off-by: Heiner Kallweit <hkallweit1@xxxxxxxxx> --- drivers/hid/hid-led.c | 20 ++++++++++++++------ 1 file changed, 14 insertions(+), 6 deletions(-) diff --git a/drivers/hid/hid-led.c b/drivers/hid/hid-led.c index d8d55f3..6c2b8e0 100644 --- a/drivers/hid/hid-led.c +++ b/drivers/hid/hid-led.c @@ -67,6 +67,8 @@ union delcom_packet { #define DELCOM_RED_LED 1 #define DELCOM_BLUE_LED 2 +#define MAX_REPORT_SIZE 16 + struct hidled_device; struct hidled_rgb; @@ -100,11 +102,10 @@ struct hidled_device { const struct hidled_config *config; struct hid_device *hdev; struct hidled_rgb *rgb; + u8 buf[MAX_REPORT_SIZE]; struct mutex lock; }; -#define MAX_REPORT_SIZE 16 - #define to_hidled_led(arg) container_of(arg, struct hidled_led, cdev) static bool riso_kagaku_switch_green_blue; @@ -118,13 +119,16 @@ static int hidled_send(struct hidled_device *ldev, __u8 *buf) mutex_lock(&ldev->lock); + /* buffer provided to hid_hw_raw_request must not be on the stack */ + memcpy(ldev->buf, buf, ldev->config->report_size); + if (ldev->config->report_type == RAW_REQUEST) - ret = hid_hw_raw_request(ldev->hdev, buf[0], buf, + ret = hid_hw_raw_request(ldev->hdev, buf[0], ldev->buf, ldev->config->report_size, HID_FEATURE_REPORT, HID_REQ_SET_REPORT); else if (ldev->config->report_type == OUTPUT_REPORT) - ret = hid_hw_output_report(ldev->hdev, buf, + ret = hid_hw_output_report(ldev->hdev, ldev->buf, ldev->config->report_size); else ret = -EINVAL; @@ -147,17 +151,21 @@ static int hidled_recv(struct hidled_device *ldev, __u8 *buf) mutex_lock(&ldev->lock); - ret = hid_hw_raw_request(ldev->hdev, buf[0], buf, + memcpy(ldev->buf, buf, ldev->config->report_size); + + ret = hid_hw_raw_request(ldev->hdev, buf[0], ldev->buf, ldev->config->report_size, HID_FEATURE_REPORT, HID_REQ_SET_REPORT); if (ret < 0) goto err; - ret = hid_hw_raw_request(ldev->hdev, buf[0], buf, + ret = hid_hw_raw_request(ldev->hdev, buf[0], ldev->buf, ldev->config->report_size, HID_FEATURE_REPORT, HID_REQ_GET_REPORT); + + memcpy(buf, ldev->buf, ldev->config->report_size); err: mutex_unlock(&ldev->lock); -- 2.10.0 -- To unsubscribe from this list: send the line "unsubscribe linux-input" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html