From mboxrd@z Thu Jan 1 00:00:00 1970 From: Peng Fan Subject: Re: Dom0 kernel panic when porting xen to new arm soc Date: Sat, 20 Jun 2015 22:47:19 +0800 Message-ID: <55857CF7.4000300@gmail.com> References: <5582D109.2000409@gmail.com> <1434639280.28264.42.camel@citrix.com> <55841799.6000406@gmail.com> <55853E20.6030700@gmail.com> <558573D0.6010207@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <558573D0.6010207@gmail.com> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org To: Julien Grall , Ian Campbell Cc: julien.grall@citrix.com, xen-devel@lists.xen.org List-Id: xen-devel@lists.xenproject.org Hi On 6/20/2015 10:08 PM, Peng Fan wrote: > Hi Julien, > > On 6/20/2015 6:19 PM, Julien Grall wrote: >> Hi, >> >> On 19/06/2015 14:22, Peng Fan wrote: >>> diff --git a/kernel/timer.c b/kernel/timer.c >>> index 38f0d40..4a025cc 100644 >>> --- a/kernel/timer.c >>> +++ b/kernel/timer.c >>> @@ -1175,6 +1175,10 @@ static inline void __run_timers(struct tvec_base >>> *base) >>> >>> base->running_timer = timer; >>> detach_expired_timer(timer, base); >>> + if (!fn) { >>> + printk("fn is null why????\n"); ----> >>> This log only shows once. Not sure why fn is null and only once. >>> + continue; >>> + } >>> >>> if (irqsafe) { >>> spin_unlock(&base->lock); >> >> By any chance, does your board has a another timer (i.e other than the >> generic timer)? > > Yeah. There is a another timer whose rating is lower that generic timer. >> >> I would also track down to see who is adding this timer. >> >>> But after apply the above kernel patch, Dom0 Linux can handle shell >>> input. >>> Just have another question, How can Dom0 handle DMA for arm. >> >> When Xen is allocating the RAM bank for DOM0 we use a direct mapping >> (i.e the Physical Address = Intermediate Address for the RAM). So DOM0 >> can perform DMA as on baremetal. > Thanks. Current, without using rootfs in sd card, my Dom0 kernel can > boot using ramfs. But if with sdhc which use ADMA, Dom0 kernel will > panic. Below is the log: > > sdhci: Secure Digital Host Controller Interface driver > sdhci: Copyright(c) Pierre Ossman > sdhci-pltfm: SDHCI platform and OF driver helper > Unable to handle kernel NULL pointer dereference at virtual address 00000000 > pgd = 80004000 > [00000000] *pgd=00000000 > Internal error: Oops: 5 [#1] PREEMPT SMP ARM > Modules linked in: > CPU: 0 PID: 1 Comm: swapper/0 Not tainted 3.14.38-02383-g5ccf32b-dirty #22 > task: 84074000 ti: 84078000 task.ti: 84078000 > PC is at bitmap_clear+0xc0/0xdc > LR is at bitmap_clear+0x54/0xdc > pc : [<8029deb8>] lr : [<8029de4c>] psr: 20000193 > sp : 84079d80 ip : 00000001 fp : 00000000 > r10: 00077fff r9 : 00000404 r8 : 00000001 > r7 : 00000001 r6 : 00000001 r5 : 00000000 r4 : ffffffff > r3 : 00000001 r2 : 00000001 r1 : 20000193 r0 : 00000015 > Flags: nzCv IRQs off FIQs on Mode SVC_32 ISA ARM Segment kernel > Control: 10c53c7d Table: 8800406a DAC: 00000015 > Process swapper/0 (pid: 1, stack limit = 0x84078238) > Stack: (0x84079d80 to 0x8407a000) > 9d80: 80000113 00000000 87efa000 81109918 00001000 800197f8 84128558 > 00080008 > 9da0: 84079dec 000000d0 84bfeac0 84126c10 84126c10 ffffffff 00000404 > ffffffff > 9dc0: 00000000 00000402 00000000 00000000 84126c10 80310ba8 ffffffff > 00000000 > 9de0: 00000000 00000524 84078000 00000000 00000000 ffffffff ffffffff > 84bfeac0 > 9e00: 84bfe800 8000b407 07eb0000 8116e0f8 00000000 804ee81c ffffffff > ffffffff > 9e20: 00000000 84126c10 84c92010 84bfeac0 00000000 84126c10 84126c00 > 84bfeac0 > 9e40: 84078030 804f08e4 804f03d8 84126c10 fffffdfb 8115401c 8115401c > 00000000 > 9e60: 0000010f 80362330 803622ec 84126c10 811c8098 00000000 8115401c > 80360b1c > 9e80: 84126c10 8115401c 84126c44 00000000 80de1888 80360d28 00000000 > 8115401c > 9ea0: 80360c9c 8035f10c 8406965c 84123634 8115401c 84c8bf80 8112f3c8 > 803602bc > 9ec0: 80d08314 8115401c 00000006 8115401c 00000006 8116e080 8116e080 > 8036130c > 9ee0: 00000000 80e00f78 00000006 800088dc 8400f900 80c94fe0 840bd480 > 80735184 > 9f00: 00000000 8116e080 0000150c 8012d430 00000000 811105b0 60000113 > 00000001 > 9f20: 87ffc576 8075ca38 0000010f 8004b0f0 80d66884 00000006 87ffc583 > 00000006 > 9f40: 811105a0 80e00f78 00000006 8116e080 8116e080 80da150c 0000010f > 80df4154 > 9f60: 80df4148 80da1c4c 00000006 00000006 80da150c 9355553c 84079f9c > 80731338 > 9f80: 00000000 00000000 80727254 00000000 00000000 00000000 00000000 > 00000000 > 9fa0: 00000000 8072725c 00000000 8000ecf8 00000000 00000000 00000000 > 00000000 > 9fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 > 00000000 > 9fe0: 00000000 00000000 00000000 00000000 00000013 00000000 9355553c > 9355553c > [<8029deb8>] (bitmap_clear) from [<800197f8>] > (__arm_dma_free.isra.18+0xe4/0x228) > [<800197f8>] (__arm_dma_free.isra.18) from [<80310ba8>] > (xen_swiotlb_free_coherent+0xfc/0x140) > [<80310ba8>] (xen_swiotlb_free_coherent) from [<804ee81c>] > (sdhci_add_host+0xb34/0xe64) > [<804ee81c>] (sdhci_add_host) from [<804f08e4>] > (sdhci_esdhc_imx_probe+0x50c/0x808) > [<804f08e4>] (sdhci_esdhc_imx_probe) from [<80362330>] > (platform_drv_probe+0x44/0xa4) > [<80362330>] (platform_drv_probe) from [<80360b1c>] > (driver_probe_device+0x120/0x25c) > [<80360b1c>] (driver_probe_device) from [<80360d28>] > (__driver_attach+0x8c/0x90) > [<80360d28>] (__driver_attach) from [<8035f10c>] > (bus_for_each_dev+0x60/0x94) > [<8035f10c>] (bus_for_each_dev) from [<803602bc>] > (bus_add_driver+0x148/0x1f0) > [<803602bc>] (bus_add_driver) from [<8036130c>] (driver_register+0x78/0xf8) > [<8036130c>] (driver_register) from [<800088dc>] > (do_one_initcall+0xf8/0x144) > [<800088dc>] (do_one_initcall) from [<80da1c4c>] > (kernel_init_freeable+0x138/0x1d8) > [<80da1c4c>] (kernel_init_freeable) from [<8072725c>] (kernel_init+0x8/0xf0) > [<8072725c>] (kernel_init) from [<8000ecf8>] (ret_from_fork+0x14/0x3c) > Code: 10866003 1206601f 10633006 11e02312 (e5953000) > ---[ end trace f6f103bb73cc0503 ]--- > note: swapper/0[1] exited with preempt_count 1 > Kernel panic - not syncing: Attempted to kill init! exitcode=0x0000000b > > The piece code is at here: > if (host->flags & SDHCI_USE_ADMA) { > /* > * We need to allocate descriptors for all sg entries > * (128) and potentially one alignment transfer for > * each of those entries. > */ > host->adma_desc = dma_alloc_coherent(mmc_dev(host->mmc), > ADMA_SIZE, &host->adma_addr, > GFP_KERNEL); > host->align_buffer = kmalloc(128 * 4, GFP_KERNEL); > printk("%p %p\n", host->adma_desc, host->align_buffer); ---> > Here host->adma_desc is NULL > if (!host->adma_desc || !host->align_buffer) { > dma_free_coherent(mmc_dev(host->mmc), ADMA_SIZE, > -->Trigger panic > host->adma_desc, host->adma_addr); > kfree(host->align_buffer); > > So dma_alloc_coherent failed, dma_free_coherent-->bitmap_clear trigger > Dom0 panic. 128M memory is for Dom0, dma_alloc_coherent should not fail. > Do you have any suggestions? > In my Dom0 kernel configuration:CONFIG_CMA_SIZE_MBYTES=320. But Dom0 kernel memsize is only 128M. From Dom0 kernel boot info, we can see CMA alloc 3200M failed. Anyway, I think this should not only change CONFIG_CMD_SIZE_MBYTES that simple, kernel should handle such case, but not panic. After change CONFIG_CMD_SIZE_MBYTES to 24M, the panic disappears. Another problem comes to me, with 128M for Dom0, Dom0 can printk msg to serial, but with "dom0_mem=1024M", I see nothing from serial for Dom0. >> >> Regards, >> > Thanks, > Peng. > Thanks, Peng.