From cd198aea9e8dc1a16a40ed52a6a4d42be470c151 Mon Sep 17 00:00:00 2001 From: Boqun Feng Date: Mon, 1 Nov 2021 23:00:26 +0800 Subject: [PATCH] Drivers: hv: balloon: Use VMBUS_RING_SIZE() wrapper for dm_ring_size commit 8a7eb2d476c6823cd44d8c25a6230a52417d7ef8 upstream. Baihua reported an error when boot an ARM64 guest with PAGE_SIZE=64k and BALLOON is enabled: hv_vmbus: registering driver hv_balloon hv_vmbus: probe failed for device 1eccfd72-4b41-45ef-b73a-4a6e44c12924 (-22) The cause of this is that the ringbuffer size for hv_balloon is not adjusted with VMBUS_RING_SIZE(), which makes the size not large enough for ringbuffers on guest with PAGE_SIZE=64k. Therefore use VMBUS_RING_SIZE() to calculate the ringbuffer size. Note that the old size (20 * 1024) counts a 4k header in the total size, while VMBUS_RING_SIZE() expects the parameter as the payload size, so use 16 * 1024. Cc: # 5.15.x Reported-by: Baihua Lu Signed-off-by: Boqun Feng Tested-by: Vitaly Kuznetsov Link: https://lore.kernel.org/r/20211101150026.736124-1-boqun.feng@gmail.com Signed-off-by: Wei Liu Signed-off-by: Greg Kroah-Hartman --- drivers/hv/hv_balloon.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/hv/hv_balloon.c b/drivers/hv/hv_balloon.c index 7f11ea0..ca873a3 100644 --- a/drivers/hv/hv_balloon.c +++ b/drivers/hv/hv_balloon.c @@ -480,7 +480,7 @@ module_param(pressure_report_delay, uint, (S_IRUGO | S_IWUSR)); MODULE_PARM_DESC(pressure_report_delay, "Delay in secs in reporting pressure"); static atomic_t trans_id = ATOMIC_INIT(0); -static int dm_ring_size = 20 * 1024; +static int dm_ring_size = VMBUS_RING_SIZE(16 * 1024); /* * Driver specific state. -- 2.7.4