Date: Wed, 04 Apr 2018 14:34:51 +0000 From: bugzilla-noreply@freebsd.org To: freebsd-bugs@FreeBSD.org Subject: [Bug 227285] File descriptor passing does not work reliably on SMP system (cache coherency issue?) Message-ID: <bug-227285-8-uOQD6WJwIk@https.bugs.freebsd.org/bugzilla/> In-Reply-To: <bug-227285-8@https.bugs.freebsd.org/bugzilla/> References: <bug-227285-8@https.bugs.freebsd.org/bugzilla/>
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https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=227285 --- Comment #2 from Jan Kokemüller <jan.kokemueller@gmail.com> --- Created attachment 192214 --> https://bugs.freebsd.org/bugzilla/attachment.cgi?id=192214&action=edit excerpt of Dtrace script output Here is part of the Dtrace debug log. When 'got err' is printed it means that the parent could not read the byte from the child. At this point the address of the receive sockbuf is 'fffff801071df148' and the SBS_CANTRCVMORE flag is set (CPU 1). However, further above, this sockbuf looks fine in the child (CPU 3) and there aren't any calls to socantrcvmore_locked() in the meantime. Even further above, this sockbuf was destroyed by the parent in a previous iteration (CPU 1) and therefore SBS_CANTRCVMORE is set. But this should not affect the current iteration. It looks like the memory from the child process on CPU 3 isn't made visible to CPU 1 properly. -- You are receiving this mail because: You are the assignee for the bug.
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