Re: Interface for communicating from kernel to user mode

[Peter Skvarka <ps%softinengines.com@localhost>]

> Could you break into ddb?  A stack trace of the freeze might be useful.

Two things:

1. I have NetBSD 10.1. I found crash dump:
crash> bt
__kernel_end() at 0
kern_reboot() at sys_reboot
vpanic() at vpanic+0x192
panic() at device_printf
trap() at startlwp
--- trap (number 6) ---
uiomove() at uiomove+0x4e
soreceive() at soreceive+0x7d7
__kernel_end() at ffffffff81de012a

crash dump tells about uiomove() IMHO on uipc_socket.c#1488 (inside of 
soreceive() function.


2. soo_recv() in my code calls (*s->so_receive)(...) and it is the same 
like in your older code.
Function soreceive() is set as member of s->so_receive (s is struct socket*)


My struct uio my_iovec is initialized:

char baf[64];
memset(baf, 0, sizeof(baf));
memset(&my_uio, 0, sizeof(my_uio));
my_iovec.iov_base = baf;
my_iovec.iov_len = sizeof(baf);

my_uio.uio_rw = UIO_READ;
my_uio.uio_iovcnt = 1;
my_uio.uio_iov = &my_iovec;
my_uio.uio_resid = my_iovec.iov_len;

Member uio_segflg (which can contain UIO_SYSSPACE) does not exist in 
this version.

I call s->so_receive() by this way:

struct mbuf* mbuf1 = NULL;
(*s->so_receive)(so, &mbuf1, &my_uio, NULL, NULL, NULL);

Cannot be problem that I am using separate kernel thread for receiving 
data on socket ?

Peter