Hello Namhyung Kim On 12/03/2015 02:03 AM, Namhyung Kim wrote: > Hi Michael, > > On Wed, Dec 02, 2015 at 05:14:47PM +0100, Michael Kerrisk (man-pages) wrote: >> Hello Namhyung Kim, >> >> I need some explanation here. This is not a simple >> typo fix, I believe. Why do you think the current text >> is wrong? > > Actually la_pltenter() is called regardless of the value of framesizep > but la_pltexit() is called only if la_pltenter() returns with non-zero > framesizep set. I spent long time to figure out why la_pltexit() is > not called at all. > > Quoting comments in glibc/sysdeps/x86_64/dl-trampoline.h: > > /* There's nothing in the frame size, so there > will be no call to the _dl_call_pltexit. */ > > and > > /* At this point we need to prepare new stack for the function > which has to be called. We copy the original stack to a > temporary buffer of the size specified by the 'framesize' > returned from _dl_profile_fixup */ > > > I think it's because it needs to preserve 'inregs' to be passed to > la_pltexit(). > > The _dl_profile_fixup() sets the '*framesizep' to maximum value of > what la_pltenter() sets. Please see glibc/elf/dl-runtime.c file. Thanks -- that's the kind of info I need for the commit message! I've committed your patch, with that text. Thanks for all of the info. Cheers, Michael >> >> On 11/03/2015 01:18 AM, Namhyung Kim wrote: >>> Signed-off-by: Namhyung Kim <namhyung@xxxxxxxxx> >>> --- >>> man7/rtld-audit.7 | 2 +- >>> 1 file changed, 1 insertion(+), 1 deletion(-) >>> >>> diff --git a/man7/rtld-audit.7 b/man7/rtld-audit.7 >>> index d0f7563..643bc57 100644 >>> --- a/man7/rtld-audit.7 >>> +++ b/man7/rtld-audit.7 >>> @@ -400,7 +400,7 @@ If different >>> invocations for this symbol return different values, >>> then the maximum returned value is used. >>> The >>> -.BR la_pltenter () >>> +.BR la_pltexit () >>> function is called only if this buffer is >>> explicitly set to a suitable value. >>> >>> >> >> >> -- >> Michael Kerrisk >> Linux man-pages maintainer; http://www.kernel.org/doc/man-pages/ >> Linux/UNIX System Programming Training: http://man7.org/training/ > -- Michael Kerrisk Linux man-pages maintainer; http://www.kernel.org/doc/man-pages/ Linux/UNIX System Programming Training: http://man7.org/training/ -- To unsubscribe from this list: send the line "unsubscribe linux-man" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
