diff options
Diffstat (limited to 'Documentation/kdump/kdump.txt')
-rw-r--r-- | Documentation/kdump/kdump.txt | 28 |
1 files changed, 17 insertions, 11 deletions
diff --git a/Documentation/kdump/kdump.txt b/Documentation/kdump/kdump.txt index b0f412e42791..7ff213f4becd 100644 --- a/Documentation/kdump/kdump.txt +++ b/Documentation/kdump/kdump.txt | |||
@@ -66,12 +66,18 @@ SETUP | |||
66 | CONFIG_PHYSICAL_START=0x1000000 | 66 | CONFIG_PHYSICAL_START=0x1000000 |
67 | c) Enable "/proc/vmcore support" (Optional, in Pseudo filesystems). | 67 | c) Enable "/proc/vmcore support" (Optional, in Pseudo filesystems). |
68 | CONFIG_PROC_VMCORE=y | 68 | CONFIG_PROC_VMCORE=y |
69 | 69 | d) Disable SMP support and build a UP kernel (Until it is fixed). | |
70 | Note: Options a) and b) depend upon "Configure standard kernel features | 70 | CONFIG_SMP=n |
71 | (for small systems)" (under General setup). | 71 | e) Enable "Local APIC support on uniprocessors". |
72 | Option a) also depends on CONFIG_HIGHMEM (under Processor | 72 | CONFIG_X86_UP_APIC=y |
73 | f) Enable "IO-APIC support on uniprocessors" | ||
74 | CONFIG_X86_UP_IOAPIC=y | ||
75 | |||
76 | Note: i) Options a) and b) depend upon "Configure standard kernel features | ||
77 | (for small systems)" (under General setup). | ||
78 | ii) Option a) also depends on CONFIG_HIGHMEM (under Processor | ||
73 | type and features). | 79 | type and features). |
74 | Both option a) and b) are under "Processor type and features". | 80 | iii) Both option a) and b) are under "Processor type and features". |
75 | 81 | ||
76 | 3) Boot into the first kernel. You are now ready to try out kexec-based crash | 82 | 3) Boot into the first kernel. You are now ready to try out kexec-based crash |
77 | dumps. | 83 | dumps. |
@@ -79,7 +85,7 @@ SETUP | |||
79 | 4) Load the second kernel to be booted using: | 85 | 4) Load the second kernel to be booted using: |
80 | 86 | ||
81 | kexec -p <second-kernel> --crash-dump --args-linux --append="root=<root-dev> | 87 | kexec -p <second-kernel> --crash-dump --args-linux --append="root=<root-dev> |
82 | maxcpus=1 init 1" | 88 | init 1 irqpoll" |
83 | 89 | ||
84 | Note: i) <second-kernel> has to be a vmlinux image. bzImage will not work, | 90 | Note: i) <second-kernel> has to be a vmlinux image. bzImage will not work, |
85 | as of now. | 91 | as of now. |
@@ -87,12 +93,12 @@ SETUP | |||
87 | is sufficient to represent the physical memory up to 4GB. To store | 93 | is sufficient to represent the physical memory up to 4GB. To store |
88 | headers in ELF64 format, specifiy "--elf64-core-headers" on the | 94 | headers in ELF64 format, specifiy "--elf64-core-headers" on the |
89 | kexec command line additionally. | 95 | kexec command line additionally. |
90 | iii) For now (or until it is fixed), it's best to build the | 96 | iii) Specify "irqpoll" as command line parameter. This reduces driver |
91 | second-kernel without multi-processor support, i.e., make it | 97 | initialization failures in second kernel due to shared interrupts. |
92 | a uniprocessor kernel. | ||
93 | 98 | ||
94 | 5) System reboots into the second kernel when a panic occurs. A module can be | 99 | 5) System reboots into the second kernel when a panic occurs. A module can be |
95 | written to force the panic, for testing purposes. | 100 | written to force the panic or "ALT-SysRq-c" can be used initiate a crash |
101 | dump for testing purposes. | ||
96 | 102 | ||
97 | 6) Write out the dump file using | 103 | 6) Write out the dump file using |
98 | 104 | ||
@@ -131,5 +137,5 @@ TODO | |||
131 | CONTACT | 137 | CONTACT |
132 | ======= | 138 | ======= |
133 | 139 | ||
134 | Hariprasad Nellitheertha - hari at in dot ibm dot com | ||
135 | Vivek Goyal (vgoyal@in.ibm.com) | 140 | Vivek Goyal (vgoyal@in.ibm.com) |
141 | Maneesh Soni (maneesh@in.ibm.com) | ||