From mboxrd@z Thu Jan 1 00:00:00 1970 Message-ID: <4BC7923B.1090809@domain.hid> Date: Fri, 16 Apr 2010 00:24:59 +0200 From: Jan Kiszka MIME-Version: 1.0 References: <4BC790B0.7090604@domain.hid> In-Reply-To: <4BC790B0.7090604@domain.hid> Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="------------enig5963DF3BEC0FABF86AEF2146" Sender: jan.kiszka@domain.hid Subject: Re: [Adeos-main] [Vortx86DX] What's wrong with kernels upper than 2.6.30.10 ? List-Id: General discussion about Adeos List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Gilles DOFFE Cc: adeos-main This is an OpenPGP/MIME signed message (RFC 2440 and 3156) --------------enig5963DF3BEC0FABF86AEF2146 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable Jan Kiszka wrote: > Gilles DOFFE wrote: >> Hello, >> >> I try to install a real-time Linux kernel on a Roboard based on a Vort= ex86DX >> (a x486 with TSC). >> >> All works fine with : >> Linux Kernel 2.6.30.10 >> Xenomai 2.5.1 >> Adeos patch adeos-ipipe-2.6.30.8-x86-2.4-09.patch >> >> But, for all kernels upper or equal to 2.6.31, I always get a double f= ault >> when testing WP bit. I have this double fault just after that : >> >> *Checking if this processor honours the WP bit even in supervisor mode= =2E..* >> >> I traced with some simple printk that the problem occurs in this funct= ion, >> at the end or after the call of fix_to_virt : >> >> *static noinline int do_test_wp_bit(void) >> { >> char tmp_reg; >> int flag; >> >> __asm__ __volatile__( >> " movb %0, %1 \n" >> "1: movb %1, %0 \n" >> " xorl %2, %2 \n" >> "2: \n" >> _ASM_EXTABLE(1b,2b) >> :"=3Dm" (*(char *)fix_to_virt(FIX_WP_TEST)), >> "=3Dq" (tmp_reg), >> "=3Dr" (flag) >> :"2" (1) >> :"memory"); >> >> return flag; >> }* >> >> I'm (quasi) sure that the problem is not that function, due to it work= s when >> the kernel is not patched. >> But where should I search ? >> >> Can you give me some indications ? >=20 > Does applying this patch [1] happen to change the picture? To answer myself: As the Vortex is 32-bit, this patch cannot make a difference. >=20 > If not, please provide your .config. So this is now important. Probably reproducible in a VM, thus also easily debuggable. Jan --------------enig5963DF3BEC0FABF86AEF2146 Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.9 (GNU/Linux) Comment: Using GnuPG with SUSE - http://enigmail.mozdev.org iEYEARECAAYFAkvHkjsACgkQitSsb3rl5xSU8QCgtowv4o0i3tL2hW3NCuYGkIWi 3YkAn0k2/UWJN83ygDDZcb3cZJ/zX8rL =aG19 -----END PGP SIGNATURE----- --------------enig5963DF3BEC0FABF86AEF2146--