From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pl0-x242.google.com (mail-pl0-x242.google.com [IPv6:2607:f8b0:400e:c01::242]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 3z35Zq2MX9zF0C0 for ; Fri, 22 Dec 2017 22:17:39 +1100 (AEDT) Received: by mail-pl0-x242.google.com with SMTP id 62so11289797pld.7 for ; Fri, 22 Dec 2017 03:17:39 -0800 (PST) From: Nicholas Piggin To: linuxppc-dev@lists.ozlabs.org Cc: Nicholas Piggin , "Aneesh Kumar K . V" Subject: [PATCH 3/9] powerpc/64: rtas avoid accessing paca in 32-bit mode Date: Fri, 22 Dec 2017 21:17:10 +1000 Message-Id: <20171222111716.13101-4-npiggin@gmail.com> In-Reply-To: <20171222111716.13101-1-npiggin@gmail.com> References: <20171222111716.13101-1-npiggin@gmail.com> List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Commit 177ba7c647f3 ("powerpc/mm/radix: Limit paca allocation in radix") limited the paca allocation address to 1G on pSeries because RTAS return accesses the paca in 32-bit mode: On return from RTAS we access the paca variables and we have 64 bit disabled. This requires us to limit paca in 32 bit range. Fix this by setting ppc64_rma_size to first_memblock_size/1G range. Avoid this limit by switching to 64-bit mode before accessing any memory. Signed-off-by: Nicholas Piggin --- arch/powerpc/kernel/entry_64.S | 17 +++++++++++------ 1 file changed, 11 insertions(+), 6 deletions(-) diff --git a/arch/powerpc/kernel/entry_64.S b/arch/powerpc/kernel/entry_64.S index 36878b6ee8b8..371c05fe250a 100644 --- a/arch/powerpc/kernel/entry_64.S +++ b/arch/powerpc/kernel/entry_64.S @@ -1083,6 +1083,17 @@ __enter_rtas: rtas_return_loc: FIXUP_ENDIAN + /* + * Clear RI and set SF before anything. + */ + mfmsr r6 + li r0,MSR_RI + andc r6,r6,r0 + sldi r0,r0,(MSR_SF_LG - MSR_RI_LG) + or r6,r6,r0 + sync + mtmsrd r6 + /* relocation is off at this point */ GET_PACA(r4) clrldi r4,r4,2 /* convert to realmode address */ @@ -1091,12 +1102,6 @@ rtas_return_loc: 0: mflr r3 ld r3,(1f-0b)(r3) /* get &rtas_restore_regs */ - mfmsr r6 - li r0,MSR_RI - andc r6,r6,r0 - sync - mtmsrd r6 - ld r1,PACAR1(r4) /* Restore our SP */ ld r4,PACASAVEDMSR(r4) /* Restore our MSR */ -- 2.15.0