Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit ae3b29e6 authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 

Pull x86 fixes from Thomas Gleixner:

 - Fix for a CPU hot-add deadlock in microcode update code

 - Fix for idle consolidation fallout

 - Documentation update for initial kernel direct mapping

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/mm: Add missing comments for initial kernel direct mapping
  x86/microcode: Add local mutex to fix physical CPU hot-add deadlock
  x86: Fix idle consolidation fallout
parents 652df602 cf8b166d

arch/x86/kernel/microcode_intel_early.c

+3 −2
Original line number Diff line number Diff line
@@ -487,6 +487,7 @@ static inline void show_saved_mc(void) 
#endif



#if defined(CONFIG_MICROCODE_INTEL_EARLY) && defined(CONFIG_HOTPLUG_CPU)

static DEFINE_MUTEX(x86_cpu_microcode_mutex);

/*

 * Save this mc into mc_saved_data. So it will be loaded early when a CPU is

 * hot added or resumes.
@@ -507,7 +508,7 @@ int save_mc_for_early(u8 *mc) 
	 * Hold hotplug lock so mc_saved_data is not accessed by a CPU in

	 * hotplug.

	 */

	cpu_hotplug_driver_lock();

	mutex_lock(&x86_cpu_microcode_mutex);



	mc_saved_count_init = mc_saved_data.mc_saved_count;

	mc_saved_count = mc_saved_data.mc_saved_count;
@@ -544,7 +545,7 @@ int save_mc_for_early(u8 *mc) 
	}



out:

	cpu_hotplug_driver_unlock();

	mutex_unlock(&x86_cpu_microcode_mutex);



	return ret;

}

arch/x86/kernel/process.c

+2 −3
Original line number Diff line number Diff line
@@ -312,6 +312,8 @@ void arch_cpu_idle(void) 
{

	if (cpuidle_idle_call())

		x86_idle();

	else

		local_irq_enable();

}



/*
@@ -368,9 +370,6 @@ void amd_e400_remove_cpu(int cpu) 
 */

static void amd_e400_idle(void)

{

	if (need_resched())

		return;



	if (!amd_e400_c1e_detected) {

		u32 lo, hi;

arch/x86/mm/init.c

+18 −1
Original line number Diff line number Diff line
@@ -359,7 +359,17 @@ unsigned long __init_refok init_memory_mapping(unsigned long start, 
}



/*

 * would have hole in the middle or ends, and only ram parts will be mapped.

 * We need to iterate through the E820 memory map and create direct mappings

 * for only E820_RAM and E820_KERN_RESERVED regions. We cannot simply

 * create direct mappings for all pfns from [0 to max_low_pfn) and

 * [4GB to max_pfn) because of possible memory holes in high addresses

 * that cannot be marked as UC by fixed/variable range MTRRs.

 * Depending on the alignment of E820 ranges, this may possibly result

 * in using smaller size (i.e. 4K instead of 2M or 1G) page tables.

 *

 * init_mem_mapping() calls init_range_memory_mapping() with big range.

 * That range would have hole in the middle or ends, and only ram parts

 * will be mapped in init_range_memory_mapping().

 */

static unsigned long __init init_range_memory_mapping(

					   unsigned long r_start,
@@ -419,6 +429,13 @@ void __init init_mem_mapping(void) 
	max_pfn_mapped = 0; /* will get exact value next */

	min_pfn_mapped = real_end >> PAGE_SHIFT;

	last_start = start = real_end;



	/*

	 * We start from the top (end of memory) and go to the bottom.

	 * The memblock_find_in_range() gets us a block of RAM from the

	 * end of RAM in [min_pfn_mapped, max_pfn_mapped) used as new pages

	 * for page table.

	 */

	while (last_start > ISA_END_ADDRESS) {

		if (last_start > step_size) {

			start = round_down(last_start - 1, step_size);