> -----Original Message----- > From: Vitaly Kuznetsov [mailto:vkuznets@xxxxxxxxxx] > Sent: Friday, April 10, 2015 5:48 AM > To: KY Srinivasan > Cc: devel@xxxxxxxxxxxxxxxxxxxxxx; Haiyang Zhang; linux- > kernel@xxxxxxxxxxxxxxx; Dexuan Cui; Jake Oshins > Subject: Re: [PATCH 2/3] Drivers: hv: vmbus: introduce vmbus_acpi_remove > > KY Srinivasan <kys@xxxxxxxxxxxxx> writes: > > >> -----Original Message----- > >> From: Vitaly Kuznetsov [mailto:vkuznets@xxxxxxxxxx] > >> Sent: Wednesday, January 21, 2015 11:02 AM > >> To: KY Srinivasan; devel@xxxxxxxxxxxxxxxxxxxxxx > >> Cc: Haiyang Zhang; linux-kernel@xxxxxxxxxxxxxxx; Dexuan Cui > >> Subject: [PATCH 2/3] Drivers: hv: vmbus: introduce vmbus_acpi_remove > >> > >> In case we do request_resource() in vmbus_acpi_add() we need to tear it > >> down to be able to load the driver again. Otherwise the following crash in > >> oberved when hv_vmbus unload/load sequence is performed on > >> Generation2 instance: > >> > >> [ 38.165701] BUG: unable to handle kernel paging request at > ffffffffa00075a0 > >> [ 38.166315] IP: [<ffffffff8107dc5f>] __request_resource+0x2f/0x50 > >> [ 38.166315] PGD 1f34067 PUD 1f35063 PMD 3f723067 PTE 0 > >> [ 38.166315] Oops: 0000 [#1] SMP > >> [ 38.166315] Modules linked in: hv_vmbus(+) [last unloaded: hv_vmbus] > >> [ 38.166315] CPU: 0 PID: 267 Comm: modprobe Not tainted 3.19.0- > >> rc5_bug923184+ #486 > >> [ 38.166315] Hardware name: Microsoft Corporation Virtual > Machine/Virtual > >> Machine, BIOS Hyper-V UEFI Release v1.0 11/26/2012 > >> [ 38.166315] task: ffff88003f401cb0 ti: ffff88003f60c000 task.ti: > >> ffff88003f60c000 > >> [ 38.166315] RIP: 0010:[<ffffffff8107dc5f>] [<ffffffff8107dc5f>] > >> __request_resource+0x2f/0x50 > >> [ 38.166315] RSP: 0018:ffff88003f60fb58 EFLAGS: 00010286 > >> ... > >> > >> Signed-off-by: Vitaly Kuznetsov <vkuznets@xxxxxxxxxx> > >> --- > >> drivers/hv/vmbus_drv.c | 10 ++++++++++ > >> 1 file changed, 10 insertions(+) > >> > >> diff --git a/drivers/hv/vmbus_drv.c b/drivers/hv/vmbus_drv.c index > >> 4d6b269..b06cb87 100644 > >> --- a/drivers/hv/vmbus_drv.c > >> +++ b/drivers/hv/vmbus_drv.c > >> @@ -902,6 +902,15 @@ acpi_walk_err: > >> return ret_val; > >> } > >> > >> +static int vmbus_acpi_remove(struct acpi_device *device) { > >> + int ret = 0; > >> + > >> + if (hyperv_mmio.start && hyperv_mmio.end) > >> + ret = release_resource(&hyperv_mmio); > >> + return ret; > >> +} > >> + > >> static const struct acpi_device_id vmbus_acpi_device_ids[] = { > >> {"VMBUS", 0}, > >> {"VMBus", 0}, > >> @@ -914,6 +923,7 @@ static struct acpi_driver vmbus_acpi_driver = { > >> .ids = vmbus_acpi_device_ids, > >> .ops = { > >> .add = vmbus_acpi_add, > >> + .remove = vmbus_acpi_remove, > >> }, > >> }; > > > > Vitaly, > > > > Jake has sent the following patch that has fixed retrieving of the mmio > resources: > > https://lkml.org/lkml/2015/1/20/876 > > > > This patch also deals with the resource cleanup that you have in this patch. > > > > Hi K.Y., > > it looks like Jake was forced to redo his work, do you think it would > make sense to have this simple fix for mainline in the meantime? I can > rebase/resend in case you do. Please do. Thanks. K. Y > > Thanks, > > -- > Vitaly _______________________________________________ devel mailing list devel@xxxxxxxxxxxxxxxxxxxxxx http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel
