From: Arthur Kiyanovski <akiyano@amazon.com>
Date: Mon, 19 Nov 2018 12:05:20 +0200
Subject: net: ena: fix crash during failed resume from hibernation
Patch-mainline: v4.20-rc4
Git-commit: e76ad21d070f79e566ac46ce0b0584c3c93e1b43
References: bsc#1111696 bsc#1117561

During resume from hibernation if ena_restore_device fails,
ena_com_dev_reset() is called, and uses the readless read mechanism,
which was already destroyed by the call to
ena_com_mmio_reg_read_request_destroy(). This causes a NULL pointer
reference.

In this commit we switch the call order of the above two functions
to avoid this crash.

Fixes: d7703ddbd7c9 ("net: ena: fix rare bug when failed restart/resume is followed by driver removal")
Signed-off-by: Arthur Kiyanovski <akiyano@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
 drivers/net/ethernet/amazon/ena/ena_netdev.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/drivers/net/ethernet/amazon/ena/ena_netdev.c
+++ b/drivers/net/ethernet/amazon/ena/ena_netdev.c
@@ -2694,8 +2694,8 @@ err_device_destroy:
 	ena_com_abort_admin_commands(ena_dev);
 	ena_com_wait_for_abort_completion(ena_dev);
 	ena_com_admin_destroy(ena_dev);
-	ena_com_mmio_reg_read_request_destroy(ena_dev);
 	ena_com_dev_reset(ena_dev, ENA_REGS_RESET_DRIVER_INVALID_STATE);
+	ena_com_mmio_reg_read_request_destroy(ena_dev);
 err:
 	clear_bit(ENA_FLAG_DEVICE_RUNNING, &adapter->flags);
 	clear_bit(ENA_FLAG_ONGOING_RESET, &adapter->flags);