Troubleshooting Tip : FortiGate keeps rebooting with "Kernel panic - not syncing: BUG!"

[nevan]

Description	This article describes the event where the FortiGate keeps rebooting, and in the console, the crash report prints the output with 'Kernel panic - not syncing: BUG!'.
Scope	FortiGate.
Solution	If the FortiGate keeps rebooting, it is recommended to check the console report. To take the console report, the article can be followed: Technical Tip: How to create a log file of a session using PuTTY. FortiGate-101F (23:51-05.21.x.x.x.x) Ver:05000008 Serial number: FG101FTK1x.x.x.x CPU: 1400MHz Total RAM: 4 GB Initializing boot device... Initializing MAC... nplite#0 Please wait for OS to boot, or press any key to display configuration menu...... Booting OS... Initializing firewall... System is starting... Failed to insmod custom kernel module 1(1) insmod: can't read '/bin/linux-kernel-bde.o': No such file or directory insmod: can't read '/bin/linux-user-bde.o': No such file or directory Failed to insmod custom kernel module 2(1) insmod: can't read '/bin/linux-user-bde.o': No such file or directory api return err code -3 opcode 5 BCM_VLAN_CREATE_SCC len 56 request 0 reply 1 api return err code -3 opcode 7 BCM_VLAN_PORT_ADD len 56 request 0 reply 2 api return err code -3 opcode 15 BCM_VLAN_CROSS_CONNECT_ADD len 56 request 0 reply 3 System file integrity init check failed! bcm sdk 140 exit. bcm_sdk 140 is down with code 1. Kernel panic - not syncing: BUG! Call trace: [<ffffffc000085510>] dump_backtrace+0x0/0x140 [<ffffffc0004d7a7c>] dump_stack+0x14/0x1c [<ffffffc0004d8350>] panic+0xb8/0x1dc [<ffffffbffc0d5d9c>] $x+0x92c/0xdf8 [filter4] [<ffffffc000142390>] do_vfs_ioctl+0x2fc/0x58c [<ffffffc0001426c8>] sys_ioctl+0xa8/0xd0 The above crash report on the console shows Kernel Panic caused by insmod incorrect modules and timing. This also might have happened due to critical FortiGate system kernel modules and SDK components failing to load during boot.  For this crash specifically files like files like '/bin/linux-kernel-bde.o' and '/bin/linux-user-bde.o', which are essential driver modules used for hardware acceleration, were missing or corrupted.  This issue has been observed mostly in np6* units and fixed in the FortiOS versions 7.4.9, 7.6.4, and 8.0.0. It is requested to create a ticket with Fortinet Technical Assistance Center to verify if the unit is facing the same issue. Related articles: Technical Tip: Kernel Error in FortiGate and how to recover Troubleshooting Tip: How to deal with a Kernel panic