Hi,
While debugging upowerd (with Logitech Unifying receiver via hidraw),
I came across this list corruption warning. It probably has something
to do with me removing the receiver and re-inserting it while the file
descriptor to /dev/hidraw0 was still open. journalctl excerpt is on the
bottom of this message, what I did was:
1. Run upowerd under gdb (using sudo)
2. disconnect, wait for a short time and reinsert the USB receiver
3. kill upowerd (ctrl+c in gdb, confirm kill, gdb exits)
I have not yet tried to reproduce it, this is a heads-up.
Could http://lkml.org/lkml/2013/7/22/248 help with this case? I have not
seen a kernel Oops as mentioned in that report though.
Regards,
Peter
Aug 06 22:57:42 al sudo[14951]: peter : TTY=pts/8 ; PWD=/tmp/upower ; USER=root ; ENV=G_DEBUG=all ; COMMAND=/usr/bin/gdb --args /tmp/upower-build/dst/usr/lib/upower/upowerd -v
Aug 06 22:57:42 al sudo[14951]: pam_unix(sudo:session): session opened for user root by peter(uid=0)
Aug 06 22:58:11 al kernel: usb 1-1.1: USB disconnect, device number 7
Aug 06 22:58:13 al kernel: usb 1-1.1: new full-speed USB device number 8 using ehci-pci
Aug 06 22:58:13 al kernel: logitech-djreceiver 0003:046D:C52B.001B: hiddev0,hidraw0: USB HID v1.11 Device [Logitech USB Receiver] on usb-0000:00:1a.0-1.1/input2
Aug 06 22:58:13 al kernel: input: Logitech Unifying Device. Wireless PID:4013 as /devices/pci0000:00/0000:00:1a.0/usb1/1-1/1-1.1/1-1.1:1.2/0003:046D:C52B.001B/input/input21
Aug 06 22:58:13 al kernel: logitech-djdevice 0003:046D:C52B.001C: input,hidraw1: USB HID v1.11 Mouse [Logitech Unifying Device. Wireless PID:4013] on usb-0000:00:1a.0-1.1:1
Aug 06 22:58:13 al kernel: input: Logitech Unifying Device. Wireless PID:2010 as /devices/pci0000:00/0000:00:1a.0/usb1/1-1/1-1.1/1-1.1:1.2/0003:046D:C52B.001B/input/input22
Aug 06 22:58:13 al kernel: logitech-djdevice 0003:046D:C52B.001D: input,hidraw2: USB HID v1.11 Keyboard [Logitech Unifying Device. Wireless PID:2010] on usb-0000:00:1a.0-1.1:2
Aug 06 22:58:13 al mtp-probe[14989]: checking bus 1, device 8: "/sys/devices/pci0000:00/0000:00:1a.0/usb1/1-1/1-1.1"
Aug 06 22:58:13 al mtp-probe[14989]: bus: 1, device: 8 was not an MTP device
Aug 06 22:59:45 al kernel: usb 1-1.1: USB disconnect, device number 8
Aug 06 22:59:47 al kernel: usb 1-1.1: new full-speed USB device number 9 using ehci-pci
Aug 06 22:59:47 al kernel: logitech-djreceiver 0003:046D:C52B.0020: hiddev0,hidraw0: USB HID v1.11 Device [Logitech USB Receiver] on usb-0000:00:1a.0-1.1/input2
Aug 06 22:59:47 al kernel: input: Logitech Unifying Device. Wireless PID:4013 as /devices/pci0000:00/0000:00:1a.0/usb1/1-1/1-1.1/1-1.1:1.2/0003:046D:C52B.0020/input/input23
Aug 06 22:59:47 al kernel: logitech-djdevice 0003:046D:C52B.0021: input,hidraw1: USB HID v1.11 Mouse [Logitech Unifying Device. Wireless PID:4013] on usb-0000:00:1a.0-1.1:1
Aug 06 22:59:47 al kernel: input: Logitech Unifying Device. Wireless PID:2010 as /devices/pci0000:00/0000:00:1a.0/usb1/1-1/1-1.1/1-1.1:1.2/0003:046D:C52B.0020/input/input24
Aug 06 22:59:47 al kernel: logitech-djdevice 0003:046D:C52B.0022: input,hidraw2: USB HID v1.11 Keyboard [Logitech Unifying Device. Wireless PID:2010] on usb-0000:00:1a.0-1.1:2
Aug 06 22:59:47 al mtp-probe[15011]: checking bus 1, device 9: "/sys/devices/pci0000:00/0000:00:1a.0/usb1/1-1/1-1.1"
Aug 06 22:59:47 al mtp-probe[15011]: bus: 1, device: 9 was not an MTP device
Aug 06 23:02:40 al kernel: ------------[ cut here ]------------
Aug 06 23:02:40 al kernel: WARNING: CPU: 3 PID: 14954 at lib/list_debug.c:59 __list_del_entry+0xa1/0xd0()
Aug 06 23:02:40 al kernel: list_del corruption. prev->next should be ffff8801ef384c18, but was (null)
Aug 06 23:02:40 al kernel: Modules linked in: usb_storage ip_set_hash_ip xt_set ip_set nfnetlink ipt_REJECT xt_recent xt_owner xt_addrtype iptable_filter ipt_MASQUERADE iptable_nat nf_conntrack_ipv4 nf_defrag_ipv4 nf_nat_ipv4 nf_nat ip_tables xt_tcpudp nf_conntrack_ipv6 nf_defrag_ipv6 xt_LOG xt_limit sit tunnel4 ip_tunnel xt_conntrack nf_conntrack ip6table_filter ip6_tables x_tables arc4 iwldvm mac80211 pl2303 usbserial coretemp kvm_intel kvm psmouse snd_hda_codec_hdmi snd_hda_codec_via snd_hda_intel snd_hda_codec iwlwifi snd_hwdep snd_pcm cfg80211 snd_page_alloc jmb38x_ms jme memstick mii snd_timer snd soundcore i2c_i801 intel_ips mxm_wmi clevo_wmi(O) wmi bbswitch(O) autofs4 dm_crypt ahci xhci_hcd libahci sdhci_pci sdhci hid_logitech_dj usbhid hid i915 video i2c_algo_bit drm_kms_helper drm
Aug 06 23:02:40 al kernel: CPU: 3 PID: 14954 Comm: upowerd Tainted: G O 3.11.0-1-custom #1
Aug 06 23:02:40 al sudo[14951]: pam_unix(sudo:session): session closed for user root
Aug 06 23:02:40 al kernel: Hardware name: CLEVO CO. B7130 /B7130 , BIOS 6.00 08/27/2010
Aug 06 23:02:40 al kernel: 0000000000000009 ffff8801a4345b78 ffffffff81598af5 ffff8801a4345bc0
Aug 06 23:02:40 al kernel: ffff8801a4345bb0 ffffffff810456bd ffff8801ef384c18 ffff8801ef384800
Aug 06 23:02:40 al kernel: ffff8801a4257168 ffff880194e71000 ffff880232673820 ffff8801a4345c10
Aug 06 23:02:40 al kernel: Call Trace:
Aug 06 23:02:40 al kernel: [<ffffffff81598af5>] dump_stack+0x54/0x74
Aug 06 23:02:40 al kernel: [<ffffffff810456bd>] warn_slowpath_common+0x7d/0xa0
Aug 06 23:02:40 al kernel: [<ffffffff8104572c>] warn_slowpath_fmt+0x4c/0x50
Aug 06 23:02:40 al kernel: [<ffffffff812f58c1>] __list_del_entry+0xa1/0xd0
Aug 06 23:02:40 al kernel: [<ffffffff812f58fd>] list_del+0xd/0x30
Aug 06 23:02:40 al kernel: [<ffffffffa013c0a6>] hidraw_release+0x46/0xe0 [hid]
Aug 06 23:02:40 al kernel: [<ffffffff81171c74>] __fput+0xf4/0x250
Aug 06 23:02:40 al kernel: [<ffffffff81171e1e>] ____fput+0xe/0x10
Aug 06 23:02:40 al kernel: [<ffffffff810670c4>] task_work_run+0xb4/0xe0
Aug 06 23:02:40 al kernel: [<ffffffff81046ba8>] do_exit+0x2b8/0xa70
Aug 06 23:02:40 al kernel: [<ffffffff815a005c>] ? _raw_spin_unlock_irq+0x2c/0x40
Aug 06 23:02:40 al kernel: [<ffffffff810482e9>] do_group_exit+0x49/0xc0
Aug 06 23:02:40 al kernel: [<ffffffff81058c73>] get_signal_to_deliver+0x2c3/0x6e0
Aug 06 23:02:40 al kernel: [<ffffffff81058d67>] ? get_signal_to_deliver+0x3b7/0x6e0
Aug 06 23:02:40 al kernel: [<ffffffff810023d8>] do_signal+0x48/0x8b0
Aug 06 23:02:40 al kernel: [<ffffffff811394d7>] ? might_fault+0x57/0xb0
Aug 06 23:02:40 al kernel: [<ffffffff815a90c0>] ? sysret_signal+0x5/0x47
Aug 06 23:02:40 al kernel: [<ffffffff81002ca5>] do_notify_resume+0x65/0x80
Aug 06 23:02:40 al kernel: [<ffffffff815a9352>] int_signal+0x12/0x17
Aug 06 23:02:40 al kernel: ---[ end trace cb12de73e428a7e2 ]---
Aug 06 23:02:40 al kernel: ------------[ cut here ]------------
Aug 06 23:02:40 al kernel: WARNING: CPU: 3 PID: 14954 at lib/list_debug.c:59 __list_del_entry+0xa1/0xd0()
Aug 06 23:02:40 al kernel: list_del corruption. prev->next should be ffff88019126f418, but was dead000000100100
Aug 06 23:02:40 al kernel: Modules linked in: usb_storage ip_set_hash_ip xt_set ip_set nfnetlink ipt_REJECT xt_recent xt_owner xt_addrtype iptable_filter ipt_MASQUERADE iptable_nat nf_conntrack_ipv4 nf_defrag_ipv4 nf_nat_ipv4 nf_nat ip_tables xt_tcpudp nf_conntrack_ipv6 nf_defrag_ipv6 xt_LOG xt_limit sit tunnel4 ip_tunnel xt_conntrack nf_conntrack ip6table_filter ip6_tables x_tables arc4 iwldvm mac80211 pl2303 usbserial coretemp kvm_intel kvm psmouse snd_hda_codec_hdmi snd_hda_codec_via snd_hda_intel snd_hda_codec iwlwifi snd_hwdep snd_pcm cfg80211 snd_page_alloc jmb38x_ms jme memstick mii snd_timer snd soundcore i2c_i801 intel_ips mxm_wmi clevo_wmi(O) wmi bbswitch(O) autofs4 dm_crypt ahci xhci_hcd libahci sdhci_pci sdhci hid_logitech_dj usbhid hid i915 video i2c_algo_bit drm_kms_helper drm
Aug 06 23:02:40 al kernel: CPU: 3 PID: 14954 Comm: upowerd Tainted: G W O 3.11.0-1-custom #1
Aug 06 23:02:40 al kernel: Hardware name: CLEVO CO. B7130 /B7130 , BIOS 6.00 08/27/2010
Aug 06 23:02:40 al kernel: 0000000000000009 ffff8801a4345b78 ffffffff81598af5 ffff8801a4345bc0
Aug 06 23:02:40 al kernel: ffff8801a4345bb0 ffffffff810456bd ffff88019126f418 ffff88019126f000
Aug 06 23:02:40 al kernel: ffff8801a4257168 ffff880194e71000 ffff880232673820 ffff8801a4345c10
Aug 06 23:02:40 al kernel: Call Trace:
Aug 06 23:02:40 al kernel: [<ffffffff81598af5>] dump_stack+0x54/0x74
Aug 06 23:02:40 al kernel: [<ffffffff810456bd>] warn_slowpath_common+0x7d/0xa0
Aug 06 23:02:40 al kernel: [<ffffffff8104572c>] warn_slowpath_fmt+0x4c/0x50
Aug 06 23:02:40 al kernel: [<ffffffff812f58c1>] __list_del_entry+0xa1/0xd0
Aug 06 23:02:40 al kernel: [<ffffffff812f58fd>] list_del+0xd/0x30
Aug 06 23:02:40 al kernel: [<ffffffffa013c0a6>] hidraw_release+0x46/0xe0 [hid]
Aug 06 23:02:40 al kernel: [<ffffffff81171c74>] __fput+0xf4/0x250
Aug 06 23:02:40 al kernel: [<ffffffff81171e1e>] ____fput+0xe/0x10
Aug 06 23:02:40 al kernel: [<ffffffff810670c4>] task_work_run+0xb4/0xe0
Aug 06 23:02:40 al kernel: [<ffffffff81046ba8>] do_exit+0x2b8/0xa70
Aug 06 23:02:40 al kernel: [<ffffffff815a005c>] ? _raw_spin_unlock_irq+0x2c/0x40
Aug 06 23:02:40 al kernel: [<ffffffff810482e9>] do_group_exit+0x49/0xc0
Aug 06 23:02:40 al kernel: [<ffffffff81058c73>] get_signal_to_deliver+0x2c3/0x6e0
Aug 06 23:02:40 al kernel: [<ffffffff81058d67>] ? get_signal_to_deliver+0x3b7/0x6e0
Aug 06 23:02:40 al kernel: [<ffffffff810023d8>] do_signal+0x48/0x8b0
Aug 06 23:02:40 al kernel: [<ffffffff811394d7>] ? might_fault+0x57/0xb0
Aug 06 23:02:40 al kernel: [<ffffffff815a90c0>] ? sysret_signal+0x5/0x47
Aug 06 23:02:40 al kernel: [<ffffffff81002ca5>] do_notify_resume+0x65/0x80
Aug 06 23:02:40 al kernel: [<ffffffff815a9352>] int_signal+0x12/0x17
Aug 06 23:02:40 al kernel: ---[ end trace cb12de73e428a7e3 ]---
Aug 06 23:02:41 al sudo[15029]: peter : TTY=pts/8 ; PWD=/tmp/upower ; USER=root ; ENV=G_DEBUG=all ; COMMAND=/usr/bin/gdb --args /tmp/upower-build/dst/usr/lib/upower/upowerd -v
Aug 06 23:02:41 al sudo[15029]: pam_unix(sudo:session): session opened for user root by peter(uid=0)
Aug 06 23:03:20 al sudo[15029]: pam_unix(sudo:session): session closed for user root
On Tue, 6 Aug 2013, Peter Wu wrote:
> While debugging upowerd (with Logitech Unifying receiver via hidraw),
> I came across this list corruption warning.
Peter,
does the patch below fix the problem you are seeing?
---
drivers/hid/hidraw.c | 2 +-
1 files changed, 1 insertions(+), 1 deletions(-)
diff --git a/drivers/hid/hidraw.c b/drivers/hid/hidraw.c
index a745163..6f1feb2 100644
--- a/drivers/hid/hidraw.c
+++ b/drivers/hid/hidraw.c
@@ -518,7 +518,6 @@ int hidraw_connect(struct hid_device *hid)
goto out;
}
- mutex_unlock(&minors_lock);
init_waitqueue_head(&dev->wait);
INIT_LIST_HEAD(&dev->list);
@@ -528,6 +527,7 @@ int hidraw_connect(struct hid_device *hid)
dev->exist = 1;
hid->hidraw = dev;
+ mutex_unlock(&minors_lock);
out:
return result;
--
Jiri Kosina
SUSE Labs
On Wednesday 07 August 2013 03:01:26 Jiri Kosina wrote:
> On Tue, 6 Aug 2013, Peter Wu wrote:
> > While debugging upowerd (with Logitech Unifying receiver via hidraw),
> > I came across this list corruption warning.
>
> Peter,
>
> does the patch below fix the problem you are seeing?
That one is already in 3.11-rc4 as far as I can see. Also, that code can
probably simplified by moving the mutex_unlock after the out label, removing
the need to duplicate the mutex_unlock.
Remember what I said about "no Oopses"? Well, it turned out that several
memory structures were damaged which causes a general protection fault in
sock_alloc_inode and other places.
I managed to create a program that can reproduce this bug 100% in a QEMU
virtual machine with a Logitech USB receiver passed to it.
qemu-system-x86_64 -enable-kvm -m 1G -usb -usbdevice host:046d:c52b
(pass -kernel, -initrd, -append as needed)
Copy hidraw-test to initrd, boot QEMU and run `hidraw-test`. Result: instant
(= +/- 2 seconds) crash.
I have applied Manoj's patch[1] on top of 3.11-rc4 which seem to fix the issue.
One observation is that the new device is named /dev/hidraw1 instead of
/dev/hidraw0. Example:
f(){ hidraw-test /dev/hidraw$1 usb1;}
# needed for 3.11-rc4
f 1; f 1 # crash
# needed for 3.11-rc4 + patch
f 1; f 2 # ok
Regards,
Peter
[1]: http://lkml.org/lkml/2013/7/22/248
--
/* cc hidraw-test.c -o hidraw-test
* hidraw-test /dev/hidraw0 usb1; hidraw-test /dev/hidraw0 usb1;
*/
#include <unistd.h>
#include <fcntl.h>
#include <stdio.h>
#include <errno.h>
#include <string.h>
#include <stdlib.h>
int open_and_write(const char *path, const char *data) {
int sfd, r;
sfd = open(path, O_WRONLY);
if (sfd < 0) {
perror(path);
return 1;
}
r = write(sfd, data, strlen(data));
if (r < 0) {
fprintf(stderr, "write(%s, %s): %s\n",
path, data, strerror(errno));
return 1;
}
close(sfd);
return 0;
}
int dork(const char *hiddev, const char *name) {
int fd;
char c;
fd = open(hiddev, O_RDWR | O_NONBLOCK);
if (fd < 0) {
perror("open");
return 1;
}
if (open_and_write("/sys/bus/usb/drivers/usb/unbind", name))
return 1;
// does not make a difference
//sleep(1);
if (open_and_write("/sys/bus/usb/drivers/usb/bind", name))
return 1;
// allow devices to get discovered
sleep(1);
printf("read() = %zi\n", read(fd, &c, 1)); perror("read");
close(fd);
return 0;
}
int main(int argc, char **argv) {
if (argc < 3) {
fprintf(stderr, "Usage: %s /dev/hidrawN usbN\n", *argv);
return 1;
}
system("modprobe -v usbhid");
system("modprobe -v hid-logitech-dj");
dork(argv[1], argv[2]);
return 0;
}
On Wed, 7 Aug 2013, Peter Wu wrote:
> > does the patch below fix the problem you are seeing?
> That one is already in 3.11-rc4 as far as I can see. Also, that code can
> probably simplified by moving the mutex_unlock after the out label, removing
> the need to duplicate the mutex_unlock.
>
> Remember what I said about "no Oopses"? Well, it turned out that several
> memory structures were damaged which causes a general protection fault in
> sock_alloc_inode and other places.
>
> I managed to create a program that can reproduce this bug 100% in a QEMU
> virtual machine with a Logitech USB receiver passed to it.
>
> qemu-system-x86_64 -enable-kvm -m 1G -usb -usbdevice host:046d:c52b
> (pass -kernel, -initrd, -append as needed)
>
> Copy hidraw-test to initrd, boot QEMU and run `hidraw-test`. Result: instant
> (= +/- 2 seconds) crash.
>
> I have applied Manoj's patch[1] on top of 3.11-rc4 which seem to fix the issue.
> One observation is that the new device is named /dev/hidraw1 instead of
> /dev/hidraw0. Example:
>
> f(){ hidraw-test /dev/hidraw$1 usb1;}
> # needed for 3.11-rc4
> f 1; f 1 # crash
> # needed for 3.11-rc4 + patch
> f 1; f 2 # ok
>
> Regards,
> Peter
>
> [1]: http://lkml.org/lkml/2013/7/22/248
That one I am still reviewing ... can I add your Tested-by: to it when
I'll be applying it and pushing to Linus?
Thanks.
> --
> /* cc hidraw-test.c -o hidraw-test
> * hidraw-test /dev/hidraw0 usb1; hidraw-test /dev/hidraw0 usb1;
> */
> #include <unistd.h>
> #include <fcntl.h>
> #include <stdio.h>
> #include <errno.h>
> #include <string.h>
> #include <stdlib.h>
>
> int open_and_write(const char *path, const char *data) {
> int sfd, r;
>
> sfd = open(path, O_WRONLY);
> if (sfd < 0) {
> perror(path);
> return 1;
> }
>
> r = write(sfd, data, strlen(data));
> if (r < 0) {
> fprintf(stderr, "write(%s, %s): %s\n",
> path, data, strerror(errno));
> return 1;
> }
> close(sfd);
> return 0;
> }
>
> int dork(const char *hiddev, const char *name) {
> int fd;
> char c;
>
> fd = open(hiddev, O_RDWR | O_NONBLOCK);
> if (fd < 0) {
> perror("open");
> return 1;
> }
>
> if (open_and_write("/sys/bus/usb/drivers/usb/unbind", name))
> return 1;
>
> // does not make a difference
> //sleep(1);
>
> if (open_and_write("/sys/bus/usb/drivers/usb/bind", name))
> return 1;
>
> // allow devices to get discovered
> sleep(1);
>
> printf("read() = %zi\n", read(fd, &c, 1)); perror("read");
> close(fd);
> return 0;
> }
>
> int main(int argc, char **argv) {
> if (argc < 3) {
> fprintf(stderr, "Usage: %s /dev/hidrawN usbN\n", *argv);
> return 1;
> }
>
> system("modprobe -v usbhid");
> system("modprobe -v hid-logitech-dj");
>
> dork(argv[1], argv[2]);
>
> return 0;
> }
>
--
Jiri Kosina
SUSE Labs
Hi Peter,
The patch I posted was solving slab memory corruption issue which was occurring because of the race in device disconnect and device release. We found the some of the device data structure being used after free. Later we figure out the patch which was reverted earlier was solving our issue but there was still some slab memory corruption. That was due to reason that list delete of the device was called after freeing the hidraw. I protect drop_ref by mutex lock and also delete the list before calling drop_ref that solve the issue. If you are seeing memory corruption then the patch could solve your issue.
Regards
-Manoj
-----Original Message-----
From: Jiri Kosina [mailto:[email protected]]
Sent: Wednesday, August 07, 2013 7:04 PM
To: Peter Wu
Cc: [email protected]; Manoj Chourasia; [email protected]; [email protected]
Subject: Re: List corruption in hidraw_release in 3.11-rc4
On Wed, 7 Aug 2013, Peter Wu wrote:
> > does the patch below fix the problem you are seeing?
> That one is already in 3.11-rc4 as far as I can see. Also, that code
> can probably simplified by moving the mutex_unlock after the out
> label, removing the need to duplicate the mutex_unlock.
>
> Remember what I said about "no Oopses"? Well, it turned out that
> several memory structures were damaged which causes a general
> protection fault in sock_alloc_inode and other places.
>
> I managed to create a program that can reproduce this bug 100% in a
> QEMU virtual machine with a Logitech USB receiver passed to it.
>
> qemu-system-x86_64 -enable-kvm -m 1G -usb -usbdevice host:046d:c52b
> (pass -kernel, -initrd, -append as needed)
>
> Copy hidraw-test to initrd, boot QEMU and run `hidraw-test`. Result:
> instant (= +/- 2 seconds) crash.
>
> I have applied Manoj's patch[1] on top of 3.11-rc4 which seem to fix the issue.
> One observation is that the new device is named /dev/hidraw1 instead
> of /dev/hidraw0. Example:
>
> f(){ hidraw-test /dev/hidraw$1 usb1;}
> # needed for 3.11-rc4
> f 1; f 1 # crash
> # needed for 3.11-rc4 + patch
> f 1; f 2 # ok
>
> Regards,
> Peter
>
> [1]: http://lkml.org/lkml/2013/7/22/248
That one I am still reviewing ... can I add your Tested-by: to it when I'll be applying it and pushing to Linus?
Thanks.
> --
> /* cc hidraw-test.c -o hidraw-test
> * hidraw-test /dev/hidraw0 usb1; hidraw-test /dev/hidraw0 usb1; */
> #include <unistd.h> #include <fcntl.h> #include <stdio.h> #include
> <errno.h> #include <string.h> #include <stdlib.h>
>
> int open_and_write(const char *path, const char *data) {
> int sfd, r;
>
> sfd = open(path, O_WRONLY);
> if (sfd < 0) {
> perror(path);
> return 1;
> }
>
> r = write(sfd, data, strlen(data));
> if (r < 0) {
> fprintf(stderr, "write(%s, %s): %s\n",
> path, data, strerror(errno));
> return 1;
> }
> close(sfd);
> return 0;
> }
>
> int dork(const char *hiddev, const char *name) {
> int fd;
> char c;
>
> fd = open(hiddev, O_RDWR | O_NONBLOCK);
> if (fd < 0) {
> perror("open");
> return 1;
> }
>
> if (open_and_write("/sys/bus/usb/drivers/usb/unbind", name))
> return 1;
>
> // does not make a difference
> //sleep(1);
>
> if (open_and_write("/sys/bus/usb/drivers/usb/bind", name))
> return 1;
>
> // allow devices to get discovered
> sleep(1);
>
> printf("read() = %zi\n", read(fd, &c, 1)); perror("read");
> close(fd);
> return 0;
> }
>
> int main(int argc, char **argv) {
> if (argc < 3) {
> fprintf(stderr, "Usage: %s /dev/hidrawN usbN\n", *argv);
> return 1;
> }
>
> system("modprobe -v usbhid");
> system("modprobe -v hid-logitech-dj");
>
> dork(argv[1], argv[2]);
>
> return 0;
> }
>
--
Jiri Kosina
SUSE Labs
On Wednesday 07 August 2013 15:34:08 Jiri Kosina wrote:
> On Wed, 7 Aug 2013, Peter Wu wrote:
> > [..]
> > I have applied Manoj's patch[1] on top of 3.11-rc4 which seem to fix the
> > issue. One observation is that the new device is named /dev/hidraw1
> > instead of /dev/hidraw0. Example:
> >
> > f(){ hidraw-test /dev/hidraw$1 usb1;}
> > # needed for 3.11-rc4
> > f 1; f 1 # crash
> > # needed for 3.11-rc4 + patch
> > f 1; f 2 # ok
> >
> > Regards,
> > Peter
> >
> > [1]: http://lkml.org/lkml/2013/7/22/248
>
> That one I am still reviewing ... can I add your Tested-by: to it when
> I'll be applying it and pushing to Linus?
Sure, once you accept it you can add:
Tested-by: Peter Wu <[email protected]>
While you are at it, are the other functions also safe? (i.e. hidraw_poll,
that one is not protected by any locks?)
Regards,
Peter