From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from gate.crashing.org (gate.crashing.org [63.228.1.57]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client did not present a certificate) by ozlabs.org (Postfix) with ESMTPS id 0C1DADDF63 for ; Sun, 14 Dec 2008 13:46:09 +1100 (EST) Subject: Re: [PATCH][for 2.6.28] powerpc/fsl-booke: Fix problem with _tlbil_va being interrupted From: Benjamin Herrenschmidt To: Kumar Gala , Paul Mackerras In-Reply-To: <1229211183-5350-1-git-send-email-galak@kernel.crashing.org> References: <1229211183-5350-1-git-send-email-galak@kernel.crashing.org> Content-Type: text/plain Date: Sun, 14 Dec 2008 13:46:02 +1100 Message-Id: <1229222762.26324.19.camel@pasglop> Mime-Version: 1.0 Cc: linuxppc-dev@ozlabs.org List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Sat, 2008-12-13 at 17:33 -0600, Kumar Gala wrote: > An example calling sequence which we did see: > > copy_user_highpage -> kmap_atomic -> flush_tlb_page -> _tlbil_va > > We got interrupted after setting up the MAS registers before the > tlbwe and the interrupt handler that caused the interrupt also did > a kmap_atomic (ide code) and thus on returning from the interrupt > the MAS registers no longer contained the proper values. > > Since we dont save/restore MAS registers for normal interrupts we > need to disable interrupts in _tlbil_va to ensure atomicity. > > Signed-off-by: Kumar Gala Acked-by: Benjamin Herrenschmidt --- Paul, this is a 2.6.28 regression, it should probably go to Linus in case he hasn't released yet :-) Cheers, Ben.