Re: [Xenomai] Crash with longer dlopen/dlcose sequence
On 05/09/2018 12:27 PM, Edouard Tisserant wrote:
>
>>> [Xenomai] bad syscall <0xf0002>
>> #define __ARM_NR_BASE (__NR_SYSCALL_BASE+0x0f)
>> #define __ARM_NR_cacheflush (__ARM_NR_BASE+2)
>
> This special syscall is issued by Glibc in _dl_reloacate_object (see
> /elf/dl-reloc.c and /sysdeps/unix/sysv/linux/arm/dl-machine.h)
>
> As a workaround, rebuilding everything with -fPIC avoids relocation, and
> then bad syscall.
>
Thanks for digging this out. Could you try this patch, keeping the relocation
enabled in your build? TIA,
diff --git a/kernel/cobalt/arch/arm/include/asm/xenomai/syscall.h
b/kernel/cobalt/arch/arm/include/asm/xenomai/syscall.h
index 92afe8d9d..baa352181 100644
--- a/kernel/cobalt/arch/arm/include/asm/xenomai/syscall.h
+++ b/kernel/cobalt/arch/arm/include/asm/xenomai/syscall.h
@@ -33,6 +33,11 @@
#define __ARM_NR_ipipe (__NR_SYSCALL_BASE + XENO_ARM_SYSCALL)
#endif
+/*
+ * Cobalt syscall numbers can be fetched from ARM_ORIG_r0 with ARM_r7
+ * containing the Xenomai syscall marker, Linux syscalls directly from
+ * ARM_r7 (may require the OABI tweak).
+ */
#define __xn_reg_sys(__regs) ((__regs)->ARM_ORIG_r0)
/* In OABI_COMPAT mode, handle both OABI and EABI userspace syscalls */
#ifdef CONFIG_OABI_COMPAT
@@ -46,11 +51,15 @@
#define __xn_syscall(__regs) (__xn_reg_sys(__regs) & ~__COBALT_SYSCALL_BIT)
/*
- * Returns the syscall number depending on the handling core. Cobalt
- * syscall numbers can be fetched from ARM_ORIG_r0 with ARM_r7
- * containing the Xenomai syscall marker, Linux syscalls directly from
- * ARM_r7 (may require the OABI tweak).
+ * Root syscall number with predicate (valid only if
+ * !__xn_syscall_p(__regs)).
*/
+#define __xn_rootcall_p(__regs, __code)
\
+ ({ \
+ *(__code) = __xn_abi_decode(__regs);\
+ *(__code) < NR_syscalls || *(__code) >= __ARM_NR_BASE; \
+ })
+
static inline long __xn_get_syscall_nr(struct pt_regs *regs)
{
return __xn_syscall_p(regs) ? __xn_reg_sys(regs) :
__xn_abi_decode(regs);
diff --git a/kernel/cobalt/posix/syscall.c b/kernel/cobalt/posix/syscall.c
index 68700a336..058a8282b 100644
--- a/kernel/cobalt/posix/syscall.c
+++ b/kernel/cobalt/posix/syscall.c
@@ -666,10 +666,6 @@ ret_handled:
return KEVENT_STOP;
linux_syscall:
- code = __xn_get_syscall_nr(regs);
- if (code >= NR_syscalls)
- goto bad_syscall;
-
if (xnsched_root_p())
/*
* The call originates from the Linux domain, either
@@ -679,6 +675,9 @@ linux_syscall:
*/
return KEVENT_PROPAGATE;
+ if (!__xn_rootcall_p(regs, &code))
+ goto bad_syscall;
+
/*
* We know this is a Cobalt thread since it runs over the head
* domain, however the current syscall should be handled by
--
Philippe.
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[Xenomai] RTDM serial illicit call from head domain 'Xenomai'
Greetings again,
Xenomai 3.0.6, armv7, imx6, imx_uart rtdm driver
I've seen many postings about this, and about symbol wrapping, etc,
etc. I'm still
not understanding something very basic here, I'm sure.
When I run a program built with --alchemy (no --posix) skin, and I
execute these lines
of code (error checking is omitted here but being done in the real
program and not failing):
#define SER_BAUD9600/**< Baud rate for SYNC interface */
#define SYNC_DEVICE "rtser0"/**< serial device used for SYNC */
static const struct rtser_config sync_config = {
.config_mask = 0x,
.baud_rate = SER_BAUD,
.parity= RTSER_NO_PARITY,
.data_bits = RTSER_8_BITS,
.stop_bits = RTSER_1_STOPB,
.handshake = RTSER_NO_HAND,
.fifo_depth= RTSER_FIFO_DEPTH_1,
.rx_timeout= RTSER_TIMEOUT_NONE,
.tx_timeout= 1e9,
.event_timeout = 1e9,
.timestamp_history = RTSER_DEF_TIMESTAMP_HISTORY,
.event_mask= RTSER_EVENT_RXPEND,
};
fd = __RT(open)(SYNC_DEVICE,0) ;
err = __RT(ioctl)(fd, RTSER_RTIOC_SET_CONFIG, &sync_config);
I get this traceback (once only per system boot):
[ 411.088376] I-pipe: Detected illicit call from head domain 'Xenomai'
[ 411.088376] into a regular Linux service
[ 411.100666] CPU: 1 PID: 875 Comm: rtserE Not tainted
4.1.18_C01571-15S00-00.000.zimg+83fdace666 #1
[ 411.109644] Hardware name: Freescale i.MX6 Quad/DualLite (Device Tree)
[ 411.116189] Backtrace:
[ 411.118694] [<80014a64>] (dump_backtrace) from [<80014c9c>]
(show_stack+0x20/0x24)
[ 411.126280] r7: r6:0080 r5: r4:80b81c94
[ 411.132072] [<80014c7c>] (show_stack) from [<806b5f3c>]
(dump_stack+0xa0/0xc4)
[ 411.139326] [<806b5e9c>] (dump_stack) from [<800ab000>]
(ipipe_root_only+0x11c/0x188)
[ 411.147171] r9:80c58300 r8: r7:80c45380 r6:80b34e6c
r5:600d0013 r4:809abba4
[ 411.155073] [<800aaee4>] (ipipe_root_only) from [<8001f5ac>]
(ipipe_test_and_stall_root+0x18/0xc0)
[ 411.164046] r10:bc5c0024 r9: r8:40480201 r7:0005
r6:2580 r5:80bc154c
[ 411.172023] r4:80ba5c9c r3:
[ 411.175675] [<8001f594>] (ipipe_test_and_stall_root) from
[<806b8274>] (mutex_trylock+0x40/0x1ec)
[ 411.184561] r7:0005 r6:2580 r5:80bc154c r4:80ba5c9c
[ 411.190358] [<806b8234>] (mutex_trylock) from [<80580d78>]
(clk_prepare_lock+0x1c/0xfc)
[ 411.198376] r7:0005 r6:2580 r5:bece7e50 r4:bec36480
[ 411.204164] [<80580d5c>] (clk_prepare_lock) from [<80581e8c>]
(clk_core_get_rate+0x1c/0x70)
[ 411.212530] r5:bece7e50 r4:bec36480
[ 411.216180] [<80581e70>] (clk_core_get_rate) from [<80581f04>]
(clk_get_rate+0x24/0x28)
[ 411.224198] r5:bece7e50 r4:bc5c2000
[ 411.227863] [<80581ee0>] (clk_get_rate) from [<7f08d2c4>]
(rt_imx_uart_ioctl+0xa88/0xe5c [xeno_imx_uart])
[ 411.237464] [<7f08c83c>] (rt_imx_uart_ioctl [xeno_imx_uart]) from
[<8010779c>] (rtdm_fd_ioctl+0xc0/0x218)
[ 411.247048] r10:00011638 r9: r8:40480201 r7:0005
r6:bc5c r5:600d0013
[ 411.255025] r4:80c58300
[ 411.257609] [<801076e0>] (rtdm_fd_ioctl) from [<8010dc70>]
(CoBaLt_ioctl+0x18/0x1c)
[ 411.265280] r3:00011638 r2:00011638 r1:40480201
[ 411.269989] r10:bf648800 r9:c0943008 r8:8010dc58 r7:80b34e6c
r6:0001 r5:0052
[ 411.277964] r4:bece7fb0
[ 411.280548] [<8010dc58>] (CoBaLt_ioctl) from [<8011efc4>]
(ipipe_syscall_hook+0x174/0x380)
[ 411.288839] [<8011ee50>] (ipipe_syscall_hook) from [<800ad6d8>]
(__ipipe_notify_syscall+0xa4/0x3e0)
[ 411.297899] r10:bf648800 r9:80c45380 r8:80b34e6c r7:bf649800
r6:80c45380 r5:0001
[ 411.305873] r4:200d0013
[ 411.308464] [<800ad634>] (__ipipe_notify_syscall) from [<80010868>]
(pipeline_syscall+0x8/0x24)
[ 411.317177] r10:0002 r9:bece6000 r8:80010928 r7:000f0042
r6:0005 r5:40480201
[ 411.325153] r4:00011638
If I do not execute the ioctl call, and I instead call:
err = __RT(write)(fd,"x",1) ;
I do not get the traceback, and the write is successful. This tells me
that ioctl() path
has some kind of check in it that the write() path doesn't have. Is the
detection of a
cross-domain call something that an RTDM driver is doing or is this
something at a higher
level making these checks?
What's more, I've seen many comments that this is a problem scenario,
and that it will put
the system into a "bad state". But all of my testing says that this is
completely benign
and everything is working as I expect it to. It can't be both ways -
which way is it, and
why?
Thanks in advance,
Steve
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Re: [Xenomai] RTDM serial illicit call from head domain 'Xenomai'
I'll try to answer part of this. The detection of a cross domain call
would come form the ipipe code in the kernel. This is being called
because the ipipe debug flags are on and it's detecting the switch
from the root domain and then causing a panic so we can see the stack
trace.
I'm not sure why the ioctl call is causing this. It looks like when
we try to get the clock rate we start to access a normal Linux service
which causes the stall and triggers the panic you see in your logs.
I'm assuming in your write you aren't accessing a normal Linux
resource so we don't see the attempt to switch domains and therefore
no panic.
Panics in general happen because the system is in a "bad" state, in
this scenario it's not really "bad" we are just detecting the mode
switch and then getting enough information to fix the issue. This is
why your system seems sane, but if you hit a worse panic then your
system may not be stable enough to do anything.
-Greg
On Sat, May 12, 2018 at 5:53 PM, Steve Freyder wrote:
> Greetings again,
>
> Xenomai 3.0.6, armv7, imx6, imx_uart rtdm driver
>
> I've seen many postings about this, and about symbol wrapping, etc, etc.
> I'm still
> not understanding something very basic here, I'm sure.
>
> When I run a program built with --alchemy (no --posix) skin, and I execute
> these lines
> of code (error checking is omitted here but being done in the real program
> and not failing):
>
> #define SER_BAUD9600/**< Baud rate for SYNC interface */
> #define SYNC_DEVICE "rtser0"/**< serial device used for SYNC */
>
> static const struct rtser_config sync_config = {
> .config_mask = 0x,
> .baud_rate = SER_BAUD,
> .parity= RTSER_NO_PARITY,
> .data_bits = RTSER_8_BITS,
> .stop_bits = RTSER_1_STOPB,
> .handshake = RTSER_NO_HAND,
> .fifo_depth= RTSER_FIFO_DEPTH_1,
> .rx_timeout= RTSER_TIMEOUT_NONE,
> .tx_timeout= 1e9,
> .event_timeout = 1e9,
> .timestamp_history = RTSER_DEF_TIMESTAMP_HISTORY,
> .event_mask= RTSER_EVENT_RXPEND,
> };
>
> fd = __RT(open)(SYNC_DEVICE,0) ;
>
> err = __RT(ioctl)(fd, RTSER_RTIOC_SET_CONFIG, &sync_config);
>
> I get this traceback (once only per system boot):
>
>
> [ 411.088376] I-pipe: Detected illicit call from head domain 'Xenomai'
> [ 411.088376] into a regular Linux service
> [ 411.100666] CPU: 1 PID: 875 Comm: rtserE Not tainted
> 4.1.18_C01571-15S00-00.000.zimg+83fdace666 #1
> [ 411.109644] Hardware name: Freescale i.MX6 Quad/DualLite (Device Tree)
> [ 411.116189] Backtrace:
> [ 411.118694] [<80014a64>] (dump_backtrace) from [<80014c9c>]
> (show_stack+0x20/0x24)
> [ 411.126280] r7: r6:0080 r5: r4:80b81c94
> [ 411.132072] [<80014c7c>] (show_stack) from [<806b5f3c>]
> (dump_stack+0xa0/0xc4)
> [ 411.139326] [<806b5e9c>] (dump_stack) from [<800ab000>]
> (ipipe_root_only+0x11c/0x188)
> [ 411.147171] r9:80c58300 r8: r7:80c45380 r6:80b34e6c r5:600d0013
> r4:809abba4
> [ 411.155073] [<800aaee4>] (ipipe_root_only) from [<8001f5ac>]
> (ipipe_test_and_stall_root+0x18/0xc0)
> [ 411.164046] r10:bc5c0024 r9: r8:40480201 r7:0005 r6:2580
> r5:80bc154c
> [ 411.172023] r4:80ba5c9c r3:
> [ 411.175675] [<8001f594>] (ipipe_test_and_stall_root) from [<806b8274>]
> (mutex_trylock+0x40/0x1ec)
> [ 411.184561] r7:0005 r6:2580 r5:80bc154c r4:80ba5c9c
> [ 411.190358] [<806b8234>] (mutex_trylock) from [<80580d78>]
> (clk_prepare_lock+0x1c/0xfc)
> [ 411.198376] r7:0005 r6:2580 r5:bece7e50 r4:bec36480
> [ 411.204164] [<80580d5c>] (clk_prepare_lock) from [<80581e8c>]
> (clk_core_get_rate+0x1c/0x70)
> [ 411.212530] r5:bece7e50 r4:bec36480
> [ 411.216180] [<80581e70>] (clk_core_get_rate) from [<80581f04>]
> (clk_get_rate+0x24/0x28)
> [ 411.224198] r5:bece7e50 r4:bc5c2000
> [ 411.227863] [<80581ee0>] (clk_get_rate) from [<7f08d2c4>]
> (rt_imx_uart_ioctl+0xa88/0xe5c [xeno_imx_uart])
> [ 411.237464] [<7f08c83c>] (rt_imx_uart_ioctl [xeno_imx_uart]) from
> [<8010779c>] (rtdm_fd_ioctl+0xc0/0x218)
> [ 411.247048] r10:00011638 r9: r8:40480201 r7:0005 r6:bc5c
> r5:600d0013
> [ 411.255025] r4:80c58300
> [ 411.257609] [<801076e0>] (rtdm_fd_ioctl) from [<8010dc70>]
> (CoBaLt_ioctl+0x18/0x1c)
> [ 411.265280] r3:00011638 r2:00011638 r1:40480201
> [ 411.269989] r10:bf648800 r9:c0943008 r8:8010dc58 r7:80b34e6c r6:0001
> r5:0052
> [ 411.277964] r4:bece7fb0
> [ 411.280548] [<8010dc58>] (CoBaLt_ioctl) from [<8011efc4>]
> (ipipe_syscall_hook+0x174/0x380)
> [ 411.288839] [<8011ee50>] (ipipe_syscall_hook) from [<800ad6d8>]
> (__ipipe_notify_syscall+0xa4/0x3e0)
> [ 411.297899] r10:bf648800 r9:80c45380 r8:80b34e6c r7:bf649800 r6:80c45380
> r5:0001
> [ 411.305873] r4:200d0013
> [ 411.30
Re: [Xenomai] RTDM serial illicit call from head domain 'Xenomai'
So the fundamental issue here seems to be "how bad is bad enough" when
it
comes to these mode switches.
The write() call is wrapped with __RT(write)(...), so I assume it is
doing
an RTDM-based write request, and not a standard Linux write() syscall.
If
I remove that wrapper, I get an EPERM error from the un-wrapped write()
call.
Had I not been running with a debug kernel,
this would never have shown up at all as far as I have seen. Perhaps
this
imx_uart driver is improperly coded - I assume it is not part of the
standard
Xenomai code base, is that correct? Perhaps the writers of this driver
improperly mixed functions that cause the code path inside the RTDM
calling
sequence to invoke code that should not really be getting invoked
"by convention" but due to the specifics, it's known to be benign
overall,
and so when the debug code is enabled, it results in a false-positive
detect
of a generic problem scenario that in this specific case is truly
always
100% benign. If that's true, then I'm going to take this off my list
of
things to concern myself about. It's only recently that we've been
running
kernels with this debug capability enabled, so I've never seen this
before
and we have never had any issues with it at all so that tends to
suggest this
is truly benign for these specific code paths.
Thanks Greg,
Steve
On 5/12/2018 9:30 PM, Greg Gallagher wrote:
I'll try to answer part of this. The detection of a cross domain call
would come form the ipipe code in the kernel. This is being called
because the ipipe debug flags are on and it's detecting the switch
from the root domain and then causing a panic so we can see the stack
trace.
I'm not sure why the ioctl call is causing this. It looks like when
we try to get the clock rate we start to access a normal Linux service
which causes the stall and triggers the panic you see in your logs.
I'm assuming in your write you aren't accessing a normal Linux
resource so we don't see the attempt to switch domains and therefore
no panic.
Panics in general happen because the system is in a "bad" state, in
this scenario it's not really "bad" we are just detecting the mode
switch and then getting enough information to fix the issue. This is
why your system seems sane, but if you hit a worse panic then your
system may not be stable enough to do anything.
-Greg
On Sat, May 12, 2018 at 5:53 PM, Steve Freyder [1] wrote:
Greetings again,
Xenomai 3.0.6, armv7, imx6, imx_uart rtdm driver
I've seen many postings about this, and about symbol wrapping, etc, etc.
I'm still
not understanding something very basic here, I'm sure.
When I run a program built with --alchemy (no --posix) skin, and I execute
these lines
of code (error checking is omitted here but being done in the real program
and not failing):
#define SER_BAUD9600/**< Baud rate for SYNC interface */
#define SYNC_DEVICE "rtser0"/**< serial device used for SYNC */
static const struct rtser_config sync_config = {
.config_mask = 0x,
.baud_rate = SER_BAUD,
.parity= RTSER_NO_PARITY,
.data_bits = RTSER_8_BITS,
.stop_bits = RTSER_1_STOPB,
.handshake = RTSER_NO_HAND,
.fifo_depth= RTSER_FIFO_DEPTH_1,
.rx_timeout= RTSER_TIMEOUT_NONE,
.tx_timeout= 1e9,
.event_timeout = 1e9,
.timestamp_history = RTSER_DEF_TIMESTAMP_HISTORY,
.event_mask= RTSER_EVENT_RXPEND,
};
fd = __RT(open)(SYNC_DEVICE,0) ;
err = __RT(ioctl)(fd, RTSER_RTIOC_SET_CONFIG, &sync_config);
I get this traceback (once only per system boot):
[ 411.088376] I-pipe: Detected illicit call from head domain 'Xenomai'
[ 411.088376] into a regular Linux service
[ 411.100666] CPU: 1 PID: 875 Comm: rtserE Not tainted
4.1.18_C01571-15S00-00.000.zimg+83fdace666 #1
[ 411.109644] Hardware name: Freescale i.MX6 Quad/DualLite (Device Tree)
[ 411.116189] Backtrace:
[ 411.118694] [<80014a64>] (dump_backtrace) from [<80014c9c>]
(show_stack+0x20/0x24)
[ 411.126280] r7: r6:0080 r5: r4:80b81c94
[ 411.132072] [<80014c7c>] (show_stack) from [<806b5f3c>]
(dump_stack+0xa0/0xc4)
[ 411.139326] [<806b5e9c>] (dump_stack) from [<800ab000>]
(ipipe_root_only+0x11c/0x188)
[ 411.147171] r9:80c58300 r8: r7:80c45380 r6:80b34e6c r5:600d0013
r4:809abba4
[ 411.155073] [<800aaee4>] (ipipe_root_only) from [<8001f5ac>]
(ipipe_test_and_stall_root+0x18/0xc0)
[ 411.164046] r10:bc5c0024 r9: r8:40480201 r7:0005 r6:2580
r5:80bc154c
[ 411.172023] r4:80ba5c9c r3:
[ 411.175675] [<8001f594>] (ipipe_test_and_stall_root) from [<806b8274>]
(mutex_trylock+0x40/0x1ec)
[ 411.184561] r7:0005 r6:2580 r5:80bc154c r4:80ba5c9c
[ 411.190358]
Re: [Xenomai] RTDM serial illicit call from head domain 'Xenomai'
I won't say the driver is improperly written, this ioctl call may not
be expected to be used in a low latency situation. Some code maybe
expected to be called at initialization time and then never again so
it doesn't impact RT operation. The rt_imx_uart driver is part of the
Xenomai code base, I'm not 100% sure if this functions shouldn't be
called from an RTDM driver or if the author needs to be aware they
could just introduce latency when used in the rt context.
These panics aren't kernel or driver errors, we are creating them on
purpose to try to track down domain switches which could impact
latency. So as long as your latency number are acceptable you don't
need to enable the debug flag to track down domain switches and these
panics can be ignored for now.
-Greg
On Sun, May 13, 2018 at 12:07 AM, Steve Freyder wrote:
> So the fundamental issue here seems to be "how bad is bad enough" when it
> comes to these mode switches.
>
> The write() call is wrapped with __RT(write)(...), so I assume it is doing
> an RTDM-based write request, and not a standard Linux write() syscall. If
> I remove that wrapper, I get an EPERM error from the un-wrapped write()
> call.
>
> Had I not been running with a debug kernel,
> this would never have shown up at all as far as I have seen. Perhaps this
> imx_uart driver is improperly coded - I assume it is not part of the
> standard
> Xenomai code base, is that correct? Perhaps the writers of this driver
> improperly mixed functions that cause the code path inside the RTDM calling
> sequence to invoke code that should not really be getting invoked
> "by convention" but due to the specifics, it's known to be benign overall,
> and so when the debug code is enabled, it results in a false-positive detect
> of a generic problem scenario that in this specific case is truly always
> 100% benign. If that's true, then I'm going to take this off my list of
> things to concern myself about. It's only recently that we've been running
> kernels with this debug capability enabled, so I've never seen this before
> and we have never had any issues with it at all so that tends to suggest
> this
> is truly benign for these specific code paths.
>
> Thanks Greg,
> Steve
>
>
>
>
> On 5/12/2018 9:30 PM, Greg Gallagher wrote:
>
> I'll try to answer part of this. The detection of a cross domain call
> would come form the ipipe code in the kernel. This is being called
> because the ipipe debug flags are on and it's detecting the switch
> from the root domain and then causing a panic so we can see the stack
> trace.
> I'm not sure why the ioctl call is causing this. It looks like when
> we try to get the clock rate we start to access a normal Linux service
> which causes the stall and triggers the panic you see in your logs.
> I'm assuming in your write you aren't accessing a normal Linux
> resource so we don't see the attempt to switch domains and therefore
> no panic.
> Panics in general happen because the system is in a "bad" state, in
> this scenario it's not really "bad" we are just detecting the mode
> switch and then getting enough information to fix the issue. This is
> why your system seems sane, but if you hit a worse panic then your
> system may not be stable enough to do anything.
>
> -Greg
>
> On Sat, May 12, 2018 at 5:53 PM, Steve Freyder wrote:
>
> Greetings again,
>
> Xenomai 3.0.6, armv7, imx6, imx_uart rtdm driver
>
> I've seen many postings about this, and about symbol wrapping, etc, etc.
> I'm still
> not understanding something very basic here, I'm sure.
>
> When I run a program built with --alchemy (no --posix) skin, and I execute
> these lines
> of code (error checking is omitted here but being done in the real program
> and not failing):
>
> #define SER_BAUD9600/**< Baud rate for SYNC interface */
> #define SYNC_DEVICE "rtser0"/**< serial device used for SYNC */
>
> static const struct rtser_config sync_config = {
> .config_mask = 0x,
> .baud_rate = SER_BAUD,
> .parity= RTSER_NO_PARITY,
> .data_bits = RTSER_8_BITS,
> .stop_bits = RTSER_1_STOPB,
> .handshake = RTSER_NO_HAND,
> .fifo_depth= RTSER_FIFO_DEPTH_1,
> .rx_timeout= RTSER_TIMEOUT_NONE,
> .tx_timeout= 1e9,
> .event_timeout = 1e9,
> .timestamp_history = RTSER_DEF_TIMESTAMP_HISTORY,
> .event_mask= RTSER_EVENT_RXPEND,
> };
>
> fd = __RT(open)(SYNC_DEVICE,0) ;
>
> err = __RT(ioctl)(fd, RTSER_RTIOC_SET_CONFIG, &sync_config);
>
> I get this traceback (once only per system boot):
>
>
> [ 411.088376] I-pipe: Detected illicit call from head domain 'Xenomai'
> [ 411.088376] into a regular Linux service
> [ 411.100666] CPU: 1 PID: 875 Comm: rtserE Not tainted
> 4.1.18_C01571-15S00-00.000.zimg+83fdace666 #1
> [ 411.10964
