8b8b0cc1c7
The __kdump_flag ABI is overly constraining for future development. As of 2.6.27, the kernel entry point has 4 constraints: Offset 0 is the starting point for the master (boot) cpu (entered with r3 pointing to the device tree structure), offset 0x60 is code for the slave cpus (entered with r3 set to their device tree physical id), offset 0x20 is used by the iseries hypervisor, and secondary cpus must be well behaved when the first 256 bytes are copied to address 0. Placing the __kdump_flag at 0x18 is bad because: - It was taking the last 8 bytes before the iseries hypervisor data. - It was 8 bytes for a boolean flag - It had no way of identifying that the flag was present - It does leave any room for the master to add any additional code before branching, which hurts debug. - It will be unnecessarily hard for 32 bit code to be common (8 bytes) Now that we have eliminated the use of __kdump_flag in favor of the standard is_kdump_kernel(), this flag only controls run without relocating the kernel to PHYSICAL_START (0), so rename it __run_at_load. Move the flag to 0x5c, 1 word before the secondary cpu entry point at 0x60. Initialize it with "run0" to say it will run at 0 unless it is set to 1. It only exists if we are relocatable. Signed-off-by: Milton Miller <miltonm@bga.com> Signed-off-by: Michael Neuling <mikey@neuling.org> Signed-off-by: Paul Mackerras <paulus@samba.org> |
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| .. | ||
| boot | ||
| configs | ||
| include/asm | ||
| kernel | ||
| kvm | ||
| lib | ||
| math-emu | ||
| mm | ||
| oprofile | ||
| platforms | ||
| sysdev | ||
| xmon | ||
| Kconfig | ||
| Kconfig.debug | ||
| Makefile | ||