| Message ID | 20220531011157.46868-2-peterx@redhat.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | userfaultfd.2: Update to latest | expand |
Hi Peter, On 5/31/22 03:11, Peter Xu wrote: > Add a paragraph for UFFD_USER_MODE_ONLY flag that was introduced in > Linux 5.11. > > Signed-off-by: Peter Xu <peterx@redhat.com> See some minor comments below. Cheers, Alex > --- > man2/userfaultfd.2 | 14 ++++++++++++-- > 1 file changed, 12 insertions(+), 2 deletions(-) > > diff --git a/man2/userfaultfd.2 b/man2/userfaultfd.2 > index cee7c01d2..0928a76d2 100644 > --- a/man2/userfaultfd.2 > +++ b/man2/userfaultfd.2 > @@ -29,8 +29,9 @@ > userfaultfd \- create a file descriptor for handling page faults in user space > .SH SYNOPSIS > .nf > -.BR "#include <fcntl.h>" " /* Definition of " O_* " constants */" > -.BR "#include <sys/syscall.h>" " /* Definition of " SYS_* " constants */" > +.BR "#include <fcntl.h>" " /* Definition of " O_* " constants */" > +.BR "#include <sys/syscall.h>" " /* Definition of " SYS_* " constants */" > +.BR "#include <linux/userfaultfd.h>" " /* Definition of " UFFD_* " constants */" > .B #include <unistd.h> > .PP > .BI "int syscall(SYS_userfaultfd, int " flags ); > @@ -76,6 +77,15 @@ See the description of the > .BR O_NONBLOCK > flag in > .BR open (2). > +.TP > +.BR UFFD_USER_MODE_ONLY s/BR/B/ see groff_man(7): [ [...] .B [text] Set text in bold. If the macro is given no argu‐ ments, the text of the next input line is set in bold. [...] .BR bold‐text roman‐text ... Set each argument in bold and roman, alternately. ] > +This is an userfaultfd specific flag that was introduced since Linux 5.11. > +When set, the userfaultfd object will only be able to handle page faults > +originated from the userspace on the registered regions. > +When a kernel originated fault was triggered on the registered range with > +this userfaultfd, a > +.BR SIGBUS s/BR/B/ > +signal will be delivered. > .PP > When the last file descriptor referring to a userfaultfd object is closed, > all memory ranges that were registered with the object are unregistered
On Fri, Jun 03, 2022 at 07:11:05PM +0200, Alejandro Colomar wrote: > Hi Peter, > > On 5/31/22 03:11, Peter Xu wrote: > > Add a paragraph for UFFD_USER_MODE_ONLY flag that was introduced in > > Linux 5.11. > > > > Signed-off-by: Peter Xu <peterx@redhat.com> > > See some minor comments below. > > Cheers, > > Alex > > > --- > > man2/userfaultfd.2 | 14 ++++++++++++-- > > 1 file changed, 12 insertions(+), 2 deletions(-) > > > > diff --git a/man2/userfaultfd.2 b/man2/userfaultfd.2 > > index cee7c01d2..0928a76d2 100644 > > --- a/man2/userfaultfd.2 > > +++ b/man2/userfaultfd.2 > > @@ -29,8 +29,9 @@ > > userfaultfd \- create a file descriptor for handling page faults in user space > > .SH SYNOPSIS > > .nf > > -.BR "#include <fcntl.h>" " /* Definition of " O_* " constants */" > > -.BR "#include <sys/syscall.h>" " /* Definition of " SYS_* " constants */" > > +.BR "#include <fcntl.h>" " /* Definition of " O_* " constants */" > > +.BR "#include <sys/syscall.h>" " /* Definition of " SYS_* " constants */" > > +.BR "#include <linux/userfaultfd.h>" " /* Definition of " UFFD_* " constants */" > > .B #include <unistd.h> > > .PP > > .BI "int syscall(SYS_userfaultfd, int " flags ); > > @@ -76,6 +77,15 @@ See the description of the > > .BR O_NONBLOCK > > flag in > > .BR open (2). > > +.TP > > +.BR UFFD_USER_MODE_ONLY > > > s/BR/B/ > > see groff_man(7): > > [ > [...] > > .B [text] > Set text in bold. If the macro is given no argu‐ > ments, the text of the next input line is set in > bold. > > [...] > > .BR bold‐text roman‐text ... > Set each argument in bold and roman, alternately. > ] > > > +This is an userfaultfd specific flag that was introduced since Linux 5.11. > > +When set, the userfaultfd object will only be able to handle page faults > > +originated from the userspace on the registered regions. > > +When a kernel originated fault was triggered on the registered range with > > +this userfaultfd, a > > +.BR SIGBUS > > s/BR/B/ Thanks Alex, I'll fix and repost the patchset soon.
diff --git a/man2/userfaultfd.2 b/man2/userfaultfd.2 index cee7c01d2..0928a76d2 100644 --- a/man2/userfaultfd.2 +++ b/man2/userfaultfd.2 @@ -29,8 +29,9 @@ userfaultfd \- create a file descriptor for handling page faults in user space .SH SYNOPSIS .nf -.BR "#include <fcntl.h>" " /* Definition of " O_* " constants */" -.BR "#include <sys/syscall.h>" " /* Definition of " SYS_* " constants */" +.BR "#include <fcntl.h>" " /* Definition of " O_* " constants */" +.BR "#include <sys/syscall.h>" " /* Definition of " SYS_* " constants */" +.BR "#include <linux/userfaultfd.h>" " /* Definition of " UFFD_* " constants */" .B #include <unistd.h> .PP .BI "int syscall(SYS_userfaultfd, int " flags ); @@ -76,6 +77,15 @@ See the description of the .BR O_NONBLOCK flag in .BR open (2). +.TP +.BR UFFD_USER_MODE_ONLY +This is an userfaultfd specific flag that was introduced since Linux 5.11. +When set, the userfaultfd object will only be able to handle page faults +originated from the userspace on the registered regions. +When a kernel originated fault was triggered on the registered range with +this userfaultfd, a +.BR SIGBUS +signal will be delivered. .PP When the last file descriptor referring to a userfaultfd object is closed, all memory ranges that were registered with the object are unregistered
Add a paragraph for UFFD_USER_MODE_ONLY flag that was introduced in Linux 5.11. Signed-off-by: Peter Xu <peterx@redhat.com> --- man2/userfaultfd.2 | 14 ++++++++++++-- 1 file changed, 12 insertions(+), 2 deletions(-)