{"id":418,"date":"2015-02-27T17:10:50","date_gmt":"2015-02-27T16:10:50","guid":{"rendered":"http:\/\/queen.run.montefiore.ulg.ac.be\/~barbette\/?p=418"},"modified":"2015-02-27T17:10:50","modified_gmt":"2015-02-27T16:10:50","slug":"introduce-delay-between-printk-kernel-messages-at-boot","status":"publish","type":"post","link":"https:\/\/perso.uclouvain.be\/tom.barbette\/introduce-delay-between-printk-kernel-messages-at-boot\/","title":{"rendered":"Introduce delay between printk (kernel messages) at boot"},"content":{"rendered":"

If you’re developing into the linux kernel but your system is crashing at boot, the boot_delay parameter may be usefull. If you added printk messages to see what happened just before, you may use the boot_delay=XXX options to add XXX milliseconds between each printk, and therefore allow you to see each messages if the messages pass through quickly.<\/p>\n

To add this parameter, type “e” while the good entry is highlighted in the grub menu bootloader, and add boot_delay=XXX at the end of the line starting with “linux=”.<\/p>\n

This is the “quick” solution. Other posts in this blog allows you to find other solution to make the console go through a serial link in a VM for instance.<\/p>\n","protected":false},"excerpt":{"rendered":"

If you’re developing into the linux kernel but your system is crashing at boot, the boot_delay parameter may be usefull. If you added printk messages to see what happened just before, you may use the boot_delay=XXX options to add XXX milliseconds between each printk, and therefore allow you to see each messages if the messages … <\/p>\n

Continue reading “Introduce delay between printk (kernel messages) at boot”<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[69],"tags":[],"class_list":["post-418","post","type-post","status-publish","format-standard","hentry","category-os2015"],"yoast_head":"\nIntroduce delay between printk (kernel messages) at boot - Tom Barbette<\/title>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/perso.uclouvain.be\/tom.barbette\/introduce-delay-between-printk-kernel-messages-at-boot\/\" \/>\n<meta property=\"og:locale\" content=\"en_US\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"Introduce delay between printk (kernel messages) at boot - Tom Barbette\" \/>\n<meta property=\"og:description\" content=\"If you’re developing into the linux kernel but your system is crashing at boot, the boot_delay parameter may be usefull. 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