On Fri, 2020-04-24 at 00:08 +0200, Markus Gothe wrote: > Background: The executable stack is needed for MIPS and the FPU > (which > decodes any unknown instruction as well). > > There have been some patches floating around to fix this behavior > since > Linux 3.12 so probably that's why you didn't notice before upgrading. > > The 'dc' applet at least requires an executable stack and might be > why > it is triggered. (Did get a MIPS32-kernel to go crash with 'bad > stack' > when running dc -e '4 0 / p' however it's fixed in 1.31.0). > > //M
OK and I can confirm that I do get the error message on mips64 and mips32 (I just failed to notice in my automated test output). So executable stack is required for floating point on mips? Should I send a kernel patch to add && !IS_ENABLED(CONFIG_MIPS) to the warning? > > On 2020-04-23 23:39, Chris Packham wrote: > > On Thu, 2020-04-23 at 07:29 +0200, Christophe Leroy wrote: > > > Hi, > > > > > > Christophe > > > > > > Le 23/04/2020 à 03:13, Chris Packham a écrit : > > > > Hi, > > > > > > > > I'm just in the process of updating our products to Linux v5.6 > > > > and > > > > one > > > > of them produces a new warning message from the kernel about > > > > busybox > > > > (v1.31.1) > > > > > > > > kernel: process '/bin/busybox' started with executable stack > > > > > > Got similar discussion about klibc 2 monthes ago, look at > > > https://lists.zytor.com/archives/klibc/2020-February/004271.html > > > > > > > The target in question is a mips64 (octeon3). We have other > > > > targets > > > > (mips32, armv7, ppc32, ppc64) which don't complain. > > > > > > > > Some searching led me to > > > > > > > > https://lore.kernel.org/lkml/20191208171918.GC19716@avx2/ > > > > > > > > Which suggests I should be filing a bug report with the vendor > > > > so > > > > here > > > > I am. > > > > > > Did you have a look into busybox bugzilla ? > > > https://bugs.busybox.net/ > > > > I did a quick search of the mailing list didn't spot anything > > yesterday. > > > > Just now I did find https://bugs.busybox.net/show_bug.cgi?id=12801 > > which is in the ball-park. It points at uclibc + binutils 2.31. I'm > > using GNU libc and binutils 2.32. > > > > > > Here's some readelf output from the binary > > > > > > Can you perform "objdump -x " on your binary ? > > > > > > > The output is quite large so I'll link to it instead of including > > it > > in-line. > > > > https://gist.github.com/cpackham/48eeab4b8801a57ef737e3fda265cae7 > > > > Interestingly I can't see anything rwx or RWE in either output > > > > _______________________________________________ > > busybox mailing list > > [email protected] > > http://lists.busybox.net/mailman/listinfo/busybox _______________________________________________ busybox mailing list [email protected] http://lists.busybox.net/mailman/listinfo/busybox
