Commit 2f51c820 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 Ingo Molnar:
 "This fixes 3 FPU handling related bugs, an EFI boot crash and a
  runtime warning.

  The EFI fix arrived late but I didn't want to delay it to after v4.5
  because the effects are pretty bad for the systems that are affected
  by it"

[ Actually, I don't think the EFI fix really matters yet, because we
  haven't switched to the separate EFI page tables in mainline yet ]

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/efi: Fix boot crash by always mapping boot service regions into new EFI page tables
  x86/fpu: Fix eager-FPU handling on legacy FPU machines
  x86/delay: Avoid preemptible context checks in delay_mwaitx()
  x86/fpu: Revert ("x86/fpu: Disable AVX when eagerfpu is off")
  x86/fpu: Fix 'no387' regression
parents fda604a4 452308de

arch/x86/include/asm/fpu/xstate.h

+4 −5
Original line number Diff line number Diff line
@@ -20,16 +20,15 @@ 


/* Supported features which support lazy state saving */

#define XFEATURE_MASK_LAZY	(XFEATURE_MASK_FP | \

				 XFEATURE_MASK_SSE)



/* Supported features which require eager state saving */

#define XFEATURE_MASK_EAGER	(XFEATURE_MASK_BNDREGS | \

				 XFEATURE_MASK_BNDCSR | \

				 XFEATURE_MASK_SSE | \

				 XFEATURE_MASK_YMM | \

				 XFEATURE_MASK_OPMASK | \

				 XFEATURE_MASK_ZMM_Hi256 | \

				 XFEATURE_MASK_Hi16_ZMM)



/* Supported features which require eager state saving */

#define XFEATURE_MASK_EAGER	(XFEATURE_MASK_BNDREGS | XFEATURE_MASK_BNDCSR)



/* All currently supported features */

#define XCNTXT_MASK	(XFEATURE_MASK_LAZY | XFEATURE_MASK_EAGER)

arch/x86/kernel/fpu/core.c

+3 −1
Original line number Diff line number Diff line
@@ -409,8 +409,10 @@ static inline void copy_init_fpstate_to_fpregs(void) 
{

	if (use_xsave())

		copy_kernel_to_xregs(&init_fpstate.xsave, -1);

	else

	else if (static_cpu_has(X86_FEATURE_FXSR))

		copy_kernel_to_fxregs(&init_fpstate.fxsave);

	else

		copy_kernel_to_fregs(&init_fpstate.fsave);

}



/*

arch/x86/kernel/fpu/init.c

+9 −13
Original line number Diff line number Diff line
@@ -78,6 +78,7 @@ static void fpu__init_system_early_generic(struct cpuinfo_x86 *c) 
	cr0 &= ~(X86_CR0_TS | X86_CR0_EM);

	write_cr0(cr0);



	if (!test_bit(X86_FEATURE_FPU, (unsigned long *)cpu_caps_cleared)) {

		asm volatile("fninit ; fnstsw %0 ; fnstcw %1"

			     : "+m" (fsw), "+m" (fcw));
@@ -85,6 +86,7 @@ static void fpu__init_system_early_generic(struct cpuinfo_x86 *c) 
			set_cpu_cap(c, X86_FEATURE_FPU);

		else

			clear_cpu_cap(c, X86_FEATURE_FPU);

	}



#ifndef CONFIG_MATH_EMULATION

	if (!cpu_has_fpu) {
@@ -132,7 +134,7 @@ static void __init fpu__init_system_generic(void) 
	 * Set up the legacy init FPU context. (xstate init might overwrite this

	 * with a more modern format, if the CPU supports it.)

	 */

	fpstate_init_fxstate(&init_fpstate.fxsave);

	fpstate_init(&init_fpstate);



	fpu__init_system_mxcsr();

}
@@ -300,12 +302,6 @@ u64 __init fpu__get_supported_xfeatures_mask(void) 
static void __init fpu__clear_eager_fpu_features(void)

{

	setup_clear_cpu_cap(X86_FEATURE_MPX);

	setup_clear_cpu_cap(X86_FEATURE_AVX);

	setup_clear_cpu_cap(X86_FEATURE_AVX2);

	setup_clear_cpu_cap(X86_FEATURE_AVX512F);

	setup_clear_cpu_cap(X86_FEATURE_AVX512PF);

	setup_clear_cpu_cap(X86_FEATURE_AVX512ER);

	setup_clear_cpu_cap(X86_FEATURE_AVX512CD);

}



/*

arch/x86/lib/delay.c

+1 −1
Original line number Diff line number Diff line
@@ -102,7 +102,7 @@ static void delay_mwaitx(unsigned long __loops) 
		 * Use cpu_tss as a cacheline-aligned, seldomly

		 * accessed per-cpu variable as the monitor target.

		 */

		__monitorx(this_cpu_ptr(&cpu_tss), 0, 0);

		__monitorx(raw_cpu_ptr(&cpu_tss), 0, 0);



		/*

		 * AMD, like Intel, supports the EAX hint and EAX=0xf

arch/x86/platform/efi/quirks.c

+62 −17
Original line number Diff line number Diff line
@@ -130,6 +130,27 @@ efi_status_t efi_query_variable_store(u32 attributes, unsigned long size) 
}

EXPORT_SYMBOL_GPL(efi_query_variable_store);



/*

 * Helper function for efi_reserve_boot_services() to figure out if we

 * can free regions in efi_free_boot_services().

 *

 * Use this function to ensure we do not free regions owned by somebody

 * else. We must only reserve (and then free) regions:

 *

 * - Not within any part of the kernel

 * - Not the BIOS reserved area (E820_RESERVED, E820_NVS, etc)

 */

static bool can_free_region(u64 start, u64 size)

{

	if (start + size > __pa_symbol(_text) && start <= __pa_symbol(_end))

		return false;



	if (!e820_all_mapped(start, start+size, E820_RAM))

		return false;



	return true;

}



/*

 * The UEFI specification makes it clear that the operating system is free to do

 * whatever it wants with boot services code after ExitBootServices() has been
@@ -147,26 +168,50 @@ void __init efi_reserve_boot_services(void) 
		efi_memory_desc_t *md = p;

		u64 start = md->phys_addr;

		u64 size = md->num_pages << EFI_PAGE_SHIFT;

		bool already_reserved;



		if (md->type != EFI_BOOT_SERVICES_CODE &&

		    md->type != EFI_BOOT_SERVICES_DATA)

			continue;

		/* Only reserve where possible:

		 * - Not within any already allocated areas

		 * - Not over any memory area (really needed, if above?)

		 * - Not within any part of the kernel

		 * - Not the bios reserved area



		already_reserved = memblock_is_region_reserved(start, size);



		/*

		 * Because the following memblock_reserve() is paired

		 * with free_bootmem_late() for this region in

		 * efi_free_boot_services(), we must be extremely

		 * careful not to reserve, and subsequently free,

		 * critical regions of memory (like the kernel image) or

		 * those regions that somebody else has already

		 * reserved.

		 *

		 * A good example of a critical region that must not be

		 * freed is page zero (first 4Kb of memory), which may

		 * contain boot services code/data but is marked

		 * E820_RESERVED by trim_bios_range().

		 */

		if ((start + size > __pa_symbol(_text)

				&& start <= __pa_symbol(_end)) ||

			!e820_all_mapped(start, start+size, E820_RAM) ||

			memblock_is_region_reserved(start, size)) {

			/* Could not reserve, skip it */

			md->num_pages = 0;

			memblock_dbg("Could not reserve boot range [0x%010llx-0x%010llx]\n",

				     start, start+size-1);

		} else

		if (!already_reserved) {

			memblock_reserve(start, size);



			/*

			 * If we are the first to reserve the region, no

			 * one else cares about it. We own it and can

			 * free it later.

			 */

			if (can_free_region(start, size))

				continue;

		}



		/*

		 * We don't own the region. We must not free it.

		 *

		 * Setting this bit for a boot services region really

		 * doesn't make sense as far as the firmware is

		 * concerned, but it does provide us with a way to tag

		 * those regions that must not be paired with

		 * free_bootmem_late().

		 */

		md->attribute |= EFI_MEMORY_RUNTIME;

	}

}
@@ -183,8 +228,8 @@ void __init efi_free_boot_services(void) 
		    md->type != EFI_BOOT_SERVICES_DATA)

			continue;



		/* Could not reserve boot area */

		if (!size)

		/* Do not free, someone else owns it: */

		if (md->attribute & EFI_MEMORY_RUNTIME)

			continue;



		free_bootmem_late(start, size);

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