From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from ozlabs.org (ozlabs.org [IPv6:2401:3900:2:1::2]) (using TLSv1.2 with cipher ADH-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 3yjjld1P3YzDrbB for ; Fri, 24 Nov 2017 15:25:01 +1100 (AEDT) Date: Fri, 24 Nov 2017 15:24:55 +1100 From: David Gibson To: Michael Ellerman Cc: linuxppc-dev@ozlabs.org, bsingharora@gmail.com, yilzhang@redhat.com Subject: Re: [PATCH] powerpc/kexec: Fix kexec/kdump in P9 guest kernels Message-ID: <20171124042455.GB18727@umbus.fritz.box> References: <20171124035102.28051-1-mpe@ellerman.id.au> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="VrqPEDrXMn8OVzN4" In-Reply-To: <20171124035102.28051-1-mpe@ellerman.id.au> List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , --VrqPEDrXMn8OVzN4 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Fri, Nov 24, 2017 at 02:51:02PM +1100, Michael Ellerman wrote: > The code that cleans up the IAMR/AMOR before kexec'ing failed to > remember that when we're running as a guest AMOR is not writable, it's > hypervisor privileged. >=20 > They symptom is that the kexec stops before entering purgatory and > nothing else is seen on the console. If you examine the state of the > system all threads will be in the 0x700 program check handler. >=20 > Fix it by making the write to AMOR dependent on HV mode. >=20 > Fixes: 1e2a516e89fc ("powerpc/kexec: Fix radix to hash kexec due to IAMR/= AMOR") > Cc: stable@vger.kernel.org # v4.10+ > Reported-by: Yilin Zhang > Debugged-by: David Gibson > Signed-off-by: Michael Ellerman Reviewed-by: David Gibson Tested-by: David Gibson > --- > arch/powerpc/kernel/misc_64.S | 2 ++ > 1 file changed, 2 insertions(+) >=20 > diff --git a/arch/powerpc/kernel/misc_64.S b/arch/powerpc/kernel/misc_64.S > index 8ac0bd2bddb0..3280953a82cf 100644 > --- a/arch/powerpc/kernel/misc_64.S > +++ b/arch/powerpc/kernel/misc_64.S > @@ -623,7 +623,9 @@ BEGIN_FTR_SECTION > * NOTE, we rely on r0 being 0 from above. > */ > mtspr SPRN_IAMR,r0 > +BEGIN_FTR_SECTION_NESTED(42) > mtspr SPRN_AMOR,r0 > +END_FTR_SECTION_NESTED_IFSET(CPU_FTR_HVMODE, 42) > END_FTR_SECTION_IFSET(CPU_FTR_ARCH_300) > =20 > /* save regs for local vars on new stack. --=20 David Gibson | I'll have my music baroque, and my code david AT gibson.dropbear.id.au | minimalist, thank you. NOT _the_ _other_ | _way_ _around_! http://www.ozlabs.org/~dgibson --VrqPEDrXMn8OVzN4 Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQIzBAEBCAAdFiEEdfRlhq5hpmzETofcbDjKyiDZs5IFAloXnxUACgkQbDjKyiDZ s5LhzxAAgjsaztQtBRHj8hKLGpzUy8EKgYqcbFIcxegII5WydYZ84wEaU288RP1g GJejEv34nbGzjGkBAO+dpsHAGxxvHK8oUdYv7K4Ieypc/DuW5F5sYlYquKAP/C2C 6SfnJ2Nq6JO0pWnYX3U4mLBmr2kiz7qvIWDDpqYZCAfWeEF/NqxFw00b+/VeO0qL TnZd+bWYU6+zZJyPwkKgexen6r8CuMYBXRErIhOhsE6/Cmip+c6wBQ+DmwF/rcFp Vnm1TSCXiYw73QK5qS8UplvZtEyrdKQ/Q3dEDvZp5pkb+gfnR3WqGqfygtmj9HNS flC4yOhn08B7WB12u3xIlQglOUIIJOeRB1EKoj6UXccPvetnf5irg8iblosn1SUv LeCdSHpR/I+H0ypA/D1UUwkLXLp4tB71R7NYZDsGWty5osuQvtsSj+X2SG+ooVqx L/8ujsKuPGH4R6TdNqq3hAPUrkQcji5is/2h02X6BG4kvb7Q26+gp4jZ13FqKhTH UJDETj2tEyYmYoeM6j0YQUjDdKv3a/IgyMJ8caBChQSbYHwnkNFyDL0sEvn8JhSY ai7DOaicFGK8XsWuFN0TsJuaA48CcbegpaoMKIX1IQEzMtEJUqlMl4bwTONWgf+k YqU5SN8qeDW5yJFpqHO+ja0TsBmZ4gc8aMu4VP9uwAi7W8E9CXY= =8mOr -----END PGP SIGNATURE----- --VrqPEDrXMn8OVzN4--