Reserve memory for the crash-gathering kernel
Microdroid kernel now boots with the `crashkernel=<size>M` cmdline
option to reserve some memory space for use by the crashdumping kernel.
Currently, we reserve this statically, i.e. regardless of whether
ramdump is enabled or not. This can't be moved to the bootconfig because
the memory reservation happens 'before' bootconfig is read. If we move
this config to bootconfig, the kernel doesn't reserve any space.
Ideally, this shall be done conditionally. The bootloader (u-boot) will
append the option at runtime when the ramdump is enabled.
Bug: 237381762
Test: cat /proc/iomem in Microdroid shows ...
80000000-92bfffff : System RAM
80210000-827bffff : Kernel code
827c0000-8291ffff : reserved
82920000-82beffff : Kernel data
87fff000-87ffffff : reserved
8f000000-903fffff : Crash kernel
90400000-913fffff : reserved
Test: /system/bin/kexec /system/etc/microdroid_crashdump_kernel
/system/etc/microdroid_crashdump_initrd.img "1 rdinit=/bin/crashdump
nr_cpus=1 reset_devices console=hvc0 earlycon=uart8250,mmio,0x3f8" in
Microdroid works.
Change-Id: I7d8de4bbaf3c7bb40b15b478ed224acd7f543f29
diff --git a/microdroid/Android.bp b/microdroid/Android.bp
index 0e3d8eb..6e9a6de 100644
--- a/microdroid/Android.bp
+++ b/microdroid/Android.bp
@@ -243,6 +243,8 @@
"panic=-1",
"bootconfig",
"ioremap_guard",
+ // TODO(b/237381762) do this only when ramdump is enabled. (bootloader shall append this)
+ "crashkernel=17M",
]
bootimg {