* Balbir Singh <bsingharora@xxxxxxxxx> [2016-08-03 15:20:42]: > On Tue, 2016-08-02 at 18:49 +0530, Srikar Dronamraju wrote: > > Fadump kernel reserves significant number of memory blocks. On a multi-node > > machine, with CONFIG_DEFFERRED_STRUCT_PAGE support, fadump kernel fails to > > boot. Fix this by disabling deferred page struct initialisation. > > > > How much memory does a fadump kernel need? Can we bump up the limits depending > on the config. I presume when you say fadump kernel you mean kernel with > FADUMP in the config? On a regular kernel with CONFIG_FADUMP and fadump configured, 5% of the total memory is reserved for booting the kernel on crash. On crash, fadump kernel reserves the 95% memory and boots into the 5% memory that was reserved for it. It then parses the reserved 95% memory to collect the dump. The problem is not about the amount of memory thats reserved for fadump kernel. Even if we increase/decrease, we will still end up with the same issue. > BTW, I would much rather prefer a config based solution that does not select > DEFERRED_INIT if FADUMP is enabled. As Vlastimil rightly pointed out, for fadump, the same kernel is booted back at a different location when we crash. So we cannot have a config based solution. -- Thanks and Regards Srikar Dronamraju -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>