Re: 'make installkernel' succeeding on read-only fs?
On 2011/11/19 at 19:24, Alexander Best wrote: > > hi there, > just stumbled upon this little detail: > > 1) have "/" mounted read-only > 2) 'make buildkernel' > 3) 'make installkernel && echo "success"' >-> this will fail > 4) 'mount -uw /' > 5) 'make installkernel && echo "success"' >-> this will succeed > 6) 'mount -ur /' > 7) 'make installkernel && echo "success"' >-> this will succeed. why? According to mount(8), 'mount -ur /' will fail if / is already mounted read-write with any files currently opened by some processes. I think this might be your case. > > cheers. > alex > -- If you've got them by the balls, their hearts and minds will follow. ___ freebsd-toolchain@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-toolchain To unsubscribe, send any mail to "freebsd-toolchain-unsubscr...@freebsd.org"
Re: 'make installkernel' succeeding on read-only fs?
On Sun Nov 20 11, Denise H. G. wrote: > > On 2011/11/19 at 19:24, Alexander Best wrote: > > > > hi there, > > just stumbled upon this little detail: > > > > 1) have "/" mounted read-only > > 2) 'make buildkernel' > > 3) 'make installkernel && echo "success"' > >-> this will fail > > 4) 'mount -uw /' > > 5) 'make installkernel && echo "success"' > >-> this will succeed > > 6) 'mount -ur /' > > 7) 'make installkernel && echo "success"' > >-> this will succeed. why? > > According to mount(8), 'mount -ur /' will fail if / is already mounted > read-write with any files currently opened by some processes. I think > this might be your case. i'd don't think so: otaku% sudo mount -uw / otaku% echo $? 0 otaku% sudo mount -ur / otaku% echo $? 0 ...also 'mount -p' reports "/" to be read-only again. ...also during 7), mkdir(1) returns an error that "/" isn't writable. it's install(1) that claims the kernel was successfully installed into /boot/kernel, although installation of the kernel didn't succeed. i don't think this is an install(1) issue, since in 3), install(1) returns an error. i think in 7), install(1)'s output gets somehow redirected to /dev/null, and its return value isn't being preserved. i'll try to use 'mount -ufr /' in 6) and see, if that has any impact. also after 6) i'll try to run install(1) manually to see, whether it actually reports an error (then the build(7) facility is to blame) or not (in which case there's a problem with install(1) itself). cheers. alex > > > > > cheers. > > alex > > > > > > -- > If you've got them by the balls, > their hearts and minds will follow. ___ freebsd-toolchain@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-toolchain To unsubscribe, send any mail to "freebsd-toolchain-unsubscr...@freebsd.org"
Re: 'make installkernel' succeeding on read-only fs?
On Sun Nov 20 11, Alexander Best wrote: > On Sun Nov 20 11, Denise H. G. wrote: > > > > On 2011/11/19 at 19:24, Alexander Best wrote: > > > > > > hi there, > > > just stumbled upon this little detail: > > > > > > 1) have "/" mounted read-only > > > 2) 'make buildkernel' > > > 3) 'make installkernel && echo "success"' > > >-> this will fail > > > 4) 'mount -uw /' > > > 5) 'make installkernel && echo "success"' > > >-> this will succeed > > > 6) 'mount -ur /' > > > 7) 'make installkernel && echo "success"' > > >-> this will succeed. why? > > > > According to mount(8), 'mount -ur /' will fail if / is already mounted > > read-write with any files currently opened by some processes. I think > > this might be your case. > > i'd don't think so: > > otaku% sudo mount -uw / > otaku% echo $? > 0 > otaku% sudo mount -ur / > otaku% echo $? > 0 > > ...also 'mount -p' reports "/" to be read-only again. > > ...also during 7), mkdir(1) returns an error that "/" isn't writable. it's > install(1) that claims the kernel was successfully installed into > /boot/kernel, > although installation of the kernel didn't succeed. > > i don't think this is an install(1) issue, since in 3), install(1) returns an > error. i think in 7), install(1)'s output gets somehow redirected to > /dev/null, > and its return value isn't being preserved. > > i'll try to use 'mount -ufr /' in 6) and see, if that has any impact. also > after 6) i'll try to run install(1) manually to see, whether it actually > reports an error (then the build(7) facility is to blame) or not (in which > case > there's a problem with install(1) itself). MYSTERY SOLVED! ;) install gets executed with the -p option, which implies the -C option. this means that install will do a comparison of the installed kernel in /boot/kernel and the one in /usr/obj, before actually executing. during the first installkernel invocation, the files differ, so install complains. during the second invocation the files don't differ. that's why install succeeds, although "/" is mounted read-only. ;) cheers. alex > > cheers. > alex > > > > > > > > > cheers. > > > alex > > > > > > > > > > > -- > > If you've got them by the balls, > > their hearts and minds will follow. ___ freebsd-toolchain@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-toolchain To unsubscribe, send any mail to "freebsd-toolchain-unsubscr...@freebsd.org"
Re: -fstack-protector vs. -fstack-protector-all
On Sat Nov 19 11, Dimitry Andric wrote: > On 2011-11-18 15:37, Alexander Best wrote: > > what are the reasons for using -fstack-protector instead of > > -fstack-protector-all in sys/conf/kern.mk? > > My guess would be one or more of the following: > > - The price in performance is too high > - The gain in security is too low > - Some routines in the kernel are run before the whole stack protection > infrastructure is in place, ergo they can't have stack protection > - There might be other problems with -fstack-protector-all, > lib/libc/Makefile says: > > # XXX For now, we don't allow libc to be compiled with > # -fstack-protector-all because it breaks rtld. We may want to make a > librtld > # in the future to circumvent this. > SSP_CFLAGS:= > ${SSP_CFLAGS:S/^-fstack-protector-all$/-fstack-protector/} defining -fstack-protector-all in sys/conf/kern.mk will only apply it to the kernel and its components and not to world, i believe. i've been running a kernel compiled with -fstack-protector-all and haven't experienced any issues with it, so far. cheers. alex ___ freebsd-toolchain@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-toolchain To unsubscribe, send any mail to "freebsd-toolchain-unsubscr...@freebsd.org"