From owner-freebsd-current@FreeBSD.ORG Sat Oct 4 08:53:34 2014 Return-Path: Delivered-To: freebsd-current@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by hub.freebsd.org (Postfix) with ESMTPS id 3EE4E9ED; Sat, 4 Oct 2014 08:53:34 +0000 (UTC) Received: from smtp.mei.co.jp (smtp.mei.co.jp [133.183.100.20]) by mx1.freebsd.org (Postfix) with ESMTP id ED503774; Sat, 4 Oct 2014 08:53:33 +0000 (UTC) Received: from mail-gw.jp.panasonic.com ([157.8.1.157]) by smtp.mei.co.jp (8.12.11.20060614/3.7W/kc-maile12) with ESMTP id s948rQE1014904; Sat, 4 Oct 2014 17:53:26 +0900 (JST) Received: from epochmail.jp.panasonic.com ([157.8.1.130]) by mail.jp.panasonic.com (8.11.6p2/3.7W/kc-maili17) with ESMTP id s948rRA11458; Sat, 4 Oct 2014 17:53:27 +0900 Received: by epochmail.jp.panasonic.com (8.12.11.20060308/3.7W/lomi11) id s948rRTe028149; Sat, 4 Oct 2014 17:53:27 +0900 Received: from localhost by lomi11.jp.panasonic.com (8.12.11.20060308/3.7W) with ESMTP id s948rRHv028137; Sat, 4 Oct 2014 17:53:27 +0900 Date: Sat, 04 Oct 2014 17:53:26 +0900 (JST) Message-Id: <20141004.175326.766405563100788209.okuno.kohji@jp.panasonic.com> To: kostikbel@gmail.com Subject: Re: About pmap_mapdev() & pmap_unmapdev() From: Kohji Okuno In-Reply-To: <20141004082943.GN26076@kib.kiev.ua> References: <20141003215830.GK26076@kib.kiev.ua> <20141004.170036.336251378907610162.okuno.kohji@jp.panasonic.com> <20141004082943.GN26076@kib.kiev.ua> Organization: Panasonic Corporation X-Mailer: Mew version 6.5 on Emacs 24.3 / Mule 6.0 (HANACHIRUSATO) Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Cc: stable@freebsd.org, freebsd-current@freebsd.org, okuno.kohji@jp.panasonic.com X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.18-1 Precedence: list List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sat, 04 Oct 2014 08:53:34 -0000 Hi, Konstantin, > At the end of the mail is commit candidate. I did not even compiled this. > Can you test and report back, please ? Could you check the following? (1) should use kernel_pmap->pm_stats.resident_count ^^^ I'm sorry. My patch was wrong. (2) should use pmap_resident_count_inc() in amd64. I will test, later. In addtion, I have one question. In current and 10-stable, is vm_map_delete() called by kva_free()? If vm_map_delete() is called, this fix is needed in current and 10-stable, I think. Regards, Kohji Okuno > On Sat, Oct 04, 2014 at 05:00:36PM +0900, Kohji Okuno wrote: >> Hi, Konstantin, >> >> Thank you for your comment. >> And, your change is better than mine. > At the end of the mail is commit candidate. I did not even compiled this. > Can you test and report back, please ? > >> >> > Do you mean that this panic is related to missed pmap_remove() ? >> > I doubt it, since pmap_mapdev() does not establish managed mappings. >> >> Yes, pmap_mapdev() does not establish managed mappings. But, if >> kernel_pmap.pm_stats.resident_count is zero, then any managed pages >> (for example pipe_map, exec_map, or etc.) are not able to change >> unmanaged status, because pmap_remove() returns without calling >> pmap_remove_pte(). >> >> In this result, I encounterd the panic. Could you refer the following? > Yes, kmem_back() indeed uses managed mapping. > > Index: amd64/amd64/pmap.c > =================================================================== > --- amd64/amd64/pmap.c (revision 272506) > +++ amd64/amd64/pmap.c (working copy) > @@ -5040,6 +5040,9 @@ pmap_mapdev_attr(vm_paddr_t pa, vm_size_t size, in > pa = trunc_page(pa); > for (tmpsize = 0; tmpsize < size; tmpsize += PAGE_SIZE) > pmap_kenter_attr(va + tmpsize, pa + tmpsize, mode); > + PMAP_LOCK(kernel_pmap); > + kernel_pmap.pm_stats.resident_count += OFF_TO_IDX(size); > + PMAP_UNLOCK(kernel_pmap); > pmap_invalidate_range(kernel_pmap, va, va + tmpsize); > pmap_invalidate_cache_range(va, va + tmpsize); > return ((void *)(va + offset)); > Index: i386/i386/pmap.c > =================================================================== > --- i386/i386/pmap.c (revision 272506) > +++ i386/i386/pmap.c (working copy) > @@ -5066,10 +5066,14 @@ pmap_mapdev_attr(vm_paddr_t pa, vm_size_t size, in > size = roundup(offset + size, PAGE_SIZE); > pa = pa & PG_FRAME; > > - if (pa < KERNLOAD && pa + size <= KERNLOAD) > + if (pa < KERNLOAD && pa + size <= KERNLOAD) { > va = KERNBASE + pa; > - else > + } else { > va = kmem_alloc_nofault(kernel_map, size); > + PMAP_LOCK(kernel_pmap); > + kernel_pmap.pm_stats.resident_count += OFF_TO_IDX(size); > + PMAP_UNLOCK(kernel_pmap); > + } > if (!va) > panic("pmap_mapdev: Couldn't alloc kernel virtual memory"); > > _______________________________________________ > freebsd-current@freebsd.org mailing list > http://lists.freebsd.org/mailman/listinfo/freebsd-current > To unsubscribe, send any mail to "freebsd-current-unsubscribe@freebsd.org"