From 6606acc31f911306ed7404c55815b447f2c99459 Mon Sep 17 00:00:00 2001 From: Richard Weinberger Date: Sun, 12 Jun 2016 21:56:42 +0200 Subject: [PATCH] um: Setup physical memory in setup_arch() Currently UML sets up physical memory very early, long before setup_arch() was called by the kernel main function. This can cause problems when code paths in UML's memory setup code assume that the kernel is already running. i.e. when kmemleak is enabled it will evaluate current() in free_bootmem(). That early current() is undefined and UML explodes. Solve the problem by setting up physical memory in setup_arch(), at this stage the kernel has materialized and basic infrastructure such as current() works. Signed-off-by: Richard Weinberger --- arch/um/kernel/um_arch.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/arch/um/kernel/um_arch.c b/arch/um/kernel/um_arch.c index 16630e75f056d..e8175a8aa22c7 100644 --- a/arch/um/kernel/um_arch.c +++ b/arch/um/kernel/um_arch.c @@ -319,9 +319,6 @@ int __init linux_main(int argc, char **argv) start_vm = VMALLOC_START; - setup_physmem(uml_physmem, uml_reserved, physmem_size, highmem); - mem_total_pages(physmem_size, iomem_size, highmem); - virtmem_size = physmem_size; stack = (unsigned long) argv; stack &= ~(1024 * 1024 - 1); @@ -334,7 +331,6 @@ int __init linux_main(int argc, char **argv) printf("Kernel virtual memory size shrunk to %lu bytes\n", virtmem_size); - stack_protections((unsigned long) &init_thread_info); os_flush_stdout(); return start_uml(); @@ -342,6 +338,10 @@ int __init linux_main(int argc, char **argv) void __init setup_arch(char **cmdline_p) { + stack_protections((unsigned long) &init_thread_info); + setup_physmem(uml_physmem, uml_reserved, physmem_size, highmem); + mem_total_pages(physmem_size, iomem_size, highmem); + paging_init(); strlcpy(boot_command_line, command_line, COMMAND_LINE_SIZE); *cmdline_p = command_line; -- 2.39.5