From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([140.186.70.92]:41284) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1RVfzG-0000US-1R for qemu-devel@nongnu.org; Wed, 30 Nov 2011 03:57:55 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1RVfzC-0008LL-Gi for qemu-devel@nongnu.org; Wed, 30 Nov 2011 03:57:54 -0500 Received: from szxga01-in.huawei.com ([119.145.14.64]:36014) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1RVfzB-0008Iq-Qy for qemu-devel@nongnu.org; Wed, 30 Nov 2011 03:57:50 -0500 Received: from huawei.com (szxga05-in [172.24.2.49]) by szxga05-in.huawei.com (iPlanet Messaging Server 5.2 HotFix 2.14 (built Aug 8 2006)) with ESMTP id <0LVG0067SSXPIO@szxga05-in.huawei.com> for qemu-devel@nongnu.org; Wed, 30 Nov 2011 16:29:49 +0800 (CST) Received: from szxrg01-dlp.huawei.com ([172.24.2.119]) by szxga05-in.huawei.com (iPlanet Messaging Server 5.2 HotFix 2.14 (built Aug 8 2006)) with ESMTP id <0LVG00E0LSXIML@szxga05-in.huawei.com> for qemu-devel@nongnu.org; Wed, 30 Nov 2011 16:29:49 +0800 (CST) Date: Wed, 30 Nov 2011 16:29:09 +0800 From: Zang Hongyong In-reply-to: <1322129109-18140-1-git-send-email-zanghongyong@huawei.com> Message-id: <4ED5E955.8020808@huawei.com> MIME-version: 1.0 Content-type: text/plain; charset=GB2312 Content-transfer-encoding: QUOTED-PRINTABLE References: <1322129109-18140-1-git-send-email-zanghongyong@huawei.com> Subject: Re: [Qemu-devel] [PATCH] ivshmem: fix guest unable to start with ioeventfd List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: wusongwei@huawei.com, kvm@vger.kernel.org, hanweidong@huawei.com, louzhengwei@huawei.com, xiaowei.yang@huawei.com, zanghongyong@huawei.com, avi@redhat.com, cam@cs.ualberta.ca Can this bug fix patch be applied yet? With this bug, guest os cannot successfully boot with ioeventfd. Thus the new PIO DoorBell patch cannot be posted. Thanks, Hongyong =D3=DA 2011/11/24,=D0=C7=C6=DA=CB=C4 18:05, zanghongyong@huawei.com = =D0=B4=B5=C0: > From: Hongyong Zang > > When a guest boots with ioeventfd, an error (by gdb) occurs: > Program received signal SIGSEGV, Segmentation fault. > 0x00000000006009cc in setup_ioeventfds (s=3D0x171dc40) > at /home/louzhengwei/git_source/qemu-kvm/hw/ivshmem.c:363 > 363 for (j =3D 0; j < s->peers[i].nb_eventfds; j++) { > The bug is due to accessing s->peers which is NULL. > > This patch uses the memory region API to replace the old one kvm_se= t_ioeventfd_mmio_long(). > And this patch makes memory_region_add_eventfd() called in ivshmem_= read() when qemu receives > eventfd information from ivshmem_server. > > Signed-off-by: Hongyong Zang > --- > hw/ivshmem.c | 41 ++++++++++++++--------------------------- > 1 files changed, 14 insertions(+), 27 deletions(-) > > diff --git a/hw/ivshmem.c b/hw/ivshmem.c > index 242fbea..be26f03 100644 > --- a/hw/ivshmem.c > +++ b/hw/ivshmem.c > @@ -58,7 +58,6 @@ typedef struct IVShmemState { > CharDriverState *server_chr; > MemoryRegion ivshmem_mmio; > =20 > - pcibus_t mmio_addr; > /* We might need to register the BAR before we actually have t= he memory. > * So prepare a container MemoryRegion for the BAR immediately= and > * add a subregion when we have the memory. > @@ -346,8 +345,14 @@ static void close_guest_eventfds(IVShmemState = *s, int posn) > guest_curr_max =3D s->peers[posn].nb_eventfds; > =20 > for (i =3D 0; i < guest_curr_max; i++) { > - kvm_set_ioeventfd_mmio_long(s->peers[posn].eventfds[i], > - s->mmio_addr + DOORBELL, (posn << 16) | i, 0); > + if (ivshmem_has_feature(s, IVSHMEM_IOEVENTFD)) { > + memory_region_del_eventfd(&s->ivshmem_mmio, > + DOORBELL, > + 4, > + true, > + (posn << 16) | i, > + s->peers[posn].eventfds[i]); > + } > close(s->peers[posn].eventfds[i]); > } > =20 > @@ -355,22 +360,6 @@ static void close_guest_eventfds(IVShmemState = *s, int posn) > s->peers[posn].nb_eventfds =3D 0; > } > =20 > -static void setup_ioeventfds(IVShmemState *s) { > - > - int i, j; > - > - for (i =3D 0; i <=3D s->max_peer; i++) { > - for (j =3D 0; j < s->peers[i].nb_eventfds; j++) { > - memory_region_add_eventfd(&s->ivshmem_mmio, > - DOORBELL, > - 4, > - true, > - (i << 16) | j, > - s->peers[i].eventfds[j]); > - } > - } > -} > - > /* this function increase the dynamic storage need to store data a= bout other > * guests */ > static void increase_dynamic_storage(IVShmemState *s, int new_min_= size) { > @@ -491,10 +480,12 @@ static void ivshmem_read(void *opaque, const = uint8_t * buf, int flags) > } > =20 > if (ivshmem_has_feature(s, IVSHMEM_IOEVENTFD)) { > - if (kvm_set_ioeventfd_mmio_long(incoming_fd, s->mmio_addr = + DOORBELL, > - (incoming_posn << 16) | guest_max_eventfd,= 1) < 0) { > - fprintf(stderr, "ivshmem: ioeventfd not available\n"); > - } > + memory_region_add_eventfd(&s->ivshmem_mmio, > + DOORBELL, > + 4, > + true, > + (incoming_posn << 16) | guest_ma= x_eventfd, > + incoming_fd); > } > =20 > return; > @@ -659,10 +650,6 @@ static int pci_ivshmem_init(PCIDevice *dev) > memory_region_init_io(&s->ivshmem_mmio, &ivshmem_mmio_ops, s, > "ivshmem-mmio", IVSHMEM_REG_BAR_SIZE); > =20 > - if (ivshmem_has_feature(s, IVSHMEM_IOEVENTFD)) { > - setup_ioeventfds(s); > - } > - > /* region for registers*/ > pci_register_bar(&s->dev, 0, PCI_BASE_ADDRESS_SPACE_MEMORY, > &s->ivshmem_mmio);