Commit 5997efb9 authored by Tom Lendacky's avatar Tom Lendacky Committed by Ingo Molnar
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x86/boot: Use memremap() to map the MPF and MPC data 



The SMP MP-table is built by UEFI and placed in memory in a decrypted
state. These tables are accessed using a mix of early_memremap(),
early_memunmap(), phys_to_virt() and virt_to_phys(). Change all accesses
to use early_memremap()/early_memunmap(). This allows for proper setting
of the encryption mask so that the data can be successfully accessed when
SME is active.

Signed-off-by: default avatarTom Lendacky <thomas.lendacky@amd.com>
Reviewed-by: default avatarThomas Gleixner <tglx@linutronix.de>
Reviewed-by: default avatarBorislav Petkov <bp@suse.de>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brijesh Singh <brijesh.singh@amd.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Larry Woodman <lwoodman@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Toshimitsu Kani <toshi.kani@hpe.com>
Cc: kasan-dev@googlegroups.com
Cc: kvm@vger.kernel.org
Cc: linux-arch@vger.kernel.org
Cc: linux-doc@vger.kernel.org
Cc: linux-efi@vger.kernel.org
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/d9464b0d7c861021ed8f494e4a40d6cd10f1eddd.1500319216.git.thomas.lendacky@amd.com


Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
parent 8f716c9b

arch/x86/kernel/mpparse.c

+70 −28
Original line number Diff line number Diff line
@@ -429,7 +429,7 @@ static inline void __init construct_default_ISA_mptable(int mpc_default_type) 
	}

}



static struct mpf_intel *mpf_found;

static unsigned long mpf_base;



static unsigned long __init get_mpc_size(unsigned long physptr)

{
@@ -451,6 +451,7 @@ static int __init check_physptr(struct mpf_intel *mpf, unsigned int early) 


	size = get_mpc_size(mpf->physptr);

	mpc = early_memremap(mpf->physptr, size);



	/*

	 * Read the physical hardware table.  Anything here will

	 * override the defaults.
@@ -497,12 +498,12 @@ static int __init check_physptr(struct mpf_intel *mpf, unsigned int early) 
 */

void __init default_get_smp_config(unsigned int early)

{

	struct mpf_intel *mpf = mpf_found;

	struct mpf_intel *mpf;



	if (!smp_found_config)

		return;



	if (!mpf)

	if (!mpf_base)

		return;



	if (acpi_lapic && early)
@@ -515,6 +516,12 @@ void __init default_get_smp_config(unsigned int early) 
	if (acpi_lapic && acpi_ioapic)

		return;



	mpf = early_memremap(mpf_base, sizeof(*mpf));

	if (!mpf) {

		pr_err("MPTABLE: error mapping MP table\n");

		return;

	}



	pr_info("Intel MultiProcessor Specification v1.%d\n",

		mpf->specification);

#if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86_32)
@@ -529,7 +536,7 @@ void __init default_get_smp_config(unsigned int early) 
	/*

	 * Now see if we need to read further.

	 */

	if (mpf->feature1 != 0) {

	if (mpf->feature1) {

		if (early) {

			/*

			 * local APIC has default address
@@ -542,8 +549,10 @@ void __init default_get_smp_config(unsigned int early) 
		construct_default_ISA_mptable(mpf->feature1);



	} else if (mpf->physptr) {

		if (check_physptr(mpf, early))

		if (check_physptr(mpf, early)) {

			early_memunmap(mpf, sizeof(*mpf));

			return;

		}

	} else

		BUG();
@@ -552,6 +561,8 @@ void __init default_get_smp_config(unsigned int early) 
	/*

	 * Only use the first configuration found.

	 */



	early_memunmap(mpf, sizeof(*mpf));

}



static void __init smp_reserve_memory(struct mpf_intel *mpf)
@@ -561,15 +572,16 @@ static void __init smp_reserve_memory(struct mpf_intel *mpf) 


static int __init smp_scan_config(unsigned long base, unsigned long length)

{

	unsigned int *bp = phys_to_virt(base);

	unsigned int *bp;

	struct mpf_intel *mpf;

	unsigned long mem;

	int ret = 0;



	apic_printk(APIC_VERBOSE, "Scan for SMP in [mem %#010lx-%#010lx]\n",

		    base, base + length - 1);

	BUILD_BUG_ON(sizeof(*mpf) != 16);



	while (length > 0) {

		bp = early_memremap(base, length);

		mpf = (struct mpf_intel *)bp;

		if ((*bp == SMP_MAGIC_IDENT) &&

		    (mpf->length == 1) &&
@@ -579,24 +591,26 @@ static int __init smp_scan_config(unsigned long base, unsigned long length) 
#ifdef CONFIG_X86_LOCAL_APIC

			smp_found_config = 1;

#endif

			mpf_found = mpf;

			mpf_base = base;



			pr_info("found SMP MP-table at [mem %#010llx-%#010llx] mapped at [%p]\n",

				(unsigned long long) virt_to_phys(mpf),

				(unsigned long long) virt_to_phys(mpf) +

				sizeof(*mpf) - 1, mpf);

			pr_info("found SMP MP-table at [mem %#010lx-%#010lx] mapped at [%p]\n",

				base, base + sizeof(*mpf) - 1, mpf);



			mem = virt_to_phys(mpf);

			memblock_reserve(mem, sizeof(*mpf));

			memblock_reserve(base, sizeof(*mpf));

			if (mpf->physptr)

				smp_reserve_memory(mpf);



			return 1;

			ret = 1;

		}

		bp += 4;

		early_memunmap(bp, length);



		if (ret)

			break;



		base += 16;

		length -= 16;

	}

	return 0;

	return ret;

}



void __init default_find_smp_config(void)
@@ -838,29 +852,40 @@ static int __init update_mp_table(void) 
	char oem[10];

	struct mpf_intel *mpf;

	struct mpc_table *mpc, *mpc_new;

	unsigned long size;



	if (!enable_update_mptable)

		return 0;



	mpf = mpf_found;

	if (!mpf)

	if (!mpf_base)

		return 0;



	mpf = early_memremap(mpf_base, sizeof(*mpf));

	if (!mpf) {

		pr_err("MPTABLE: mpf early_memremap() failed\n");

		return 0;

	}



	/*

	 * Now see if we need to go further.

	 */

	if (mpf->feature1 != 0)

		return 0;

	if (mpf->feature1)

		goto do_unmap_mpf;



	if (!mpf->physptr)

		return 0;

		goto do_unmap_mpf;



	mpc = phys_to_virt(mpf->physptr);

	size = get_mpc_size(mpf->physptr);

	mpc = early_memremap(mpf->physptr, size);

	if (!mpc) {

		pr_err("MPTABLE: mpc early_memremap() failed\n");

		goto do_unmap_mpf;

	}



	if (!smp_check_mpc(mpc, oem, str))

		return 0;

		goto do_unmap_mpc;



	pr_info("mpf: %llx\n", (u64)virt_to_phys(mpf));

	pr_info("mpf: %llx\n", (u64)mpf_base);

	pr_info("physptr: %x\n", mpf->physptr);



	if (mpc_new_phys && mpc->length > mpc_new_length) {
@@ -878,21 +903,32 @@ static int __init update_mp_table(void) 
		new = mpf_checksum((unsigned char *)mpc, mpc->length);

		if (old == new) {

			pr_info("mpc is readonly, please try alloc_mptable instead\n");

			return 0;

			goto do_unmap_mpc;

		}

		pr_info("use in-position replacing\n");

	} else {

		mpc_new = early_memremap(mpc_new_phys, mpc_new_length);

		if (!mpc_new) {

			pr_err("MPTABLE: new mpc early_memremap() failed\n");

			goto do_unmap_mpc;

		}

		mpf->physptr = mpc_new_phys;

		mpc_new = phys_to_virt(mpc_new_phys);

		memcpy(mpc_new, mpc, mpc->length);

		early_memunmap(mpc, size);

		mpc = mpc_new;

		size = mpc_new_length;

		/* check if we can modify that */

		if (mpc_new_phys - mpf->physptr) {

			struct mpf_intel *mpf_new;

			/* steal 16 bytes from [0, 1k) */

			mpf_new = early_memremap(0x400 - 16, sizeof(*mpf_new));

			if (!mpf_new) {

				pr_err("MPTABLE: new mpf early_memremap() failed\n");

				goto do_unmap_mpc;

			}

			pr_info("mpf new: %x\n", 0x400 - 16);

			mpf_new = phys_to_virt(0x400 - 16);

			memcpy(mpf_new, mpf, 16);

			early_memunmap(mpf, sizeof(*mpf));

			mpf = mpf_new;

			mpf->physptr = mpc_new_phys;

		}
@@ -909,6 +945,12 @@ static int __init update_mp_table(void) 
	 */

	replace_intsrc_all(mpc, mpc_new_phys, mpc_new_length);



do_unmap_mpc:

	early_memunmap(mpc, size);



do_unmap_mpf:

	early_memunmap(mpf, sizeof(*mpf));



	return 0;

}

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