From 5997efb967565e858259401af394e8449629c1f0 Mon Sep 17 00:00:00 2001 From: Tom Lendacky Date: Mon, 17 Jul 2017 16:10:17 -0500 Subject: [PATCH] x86/boot: Use memremap() to map the MPF and MPC data MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit 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: Tom Lendacky Reviewed-by: Thomas Gleixner Reviewed-by: Borislav Petkov Cc: Alexander Potapenko Cc: Andrey Ryabinin Cc: Andy Lutomirski Cc: Arnd Bergmann Cc: Borislav Petkov Cc: Brijesh Singh Cc: Dave Young Cc: Dmitry Vyukov Cc: Jonathan Corbet Cc: Konrad Rzeszutek Wilk Cc: Larry Woodman Cc: Linus Torvalds Cc: Matt Fleming Cc: Michael S. Tsirkin Cc: Paolo Bonzini Cc: Peter Zijlstra Cc: Radim Krčmář Cc: Rik van Riel Cc: Toshimitsu Kani 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: Ingo Molnar --- arch/x86/kernel/mpparse.c | 98 +++++++++++++++++++++++++++++++++-------------- 1 file changed, 70 insertions(+), 28 deletions(-) diff --git a/arch/x86/kernel/mpparse.c b/arch/x86/kernel/mpparse.c index fd37f39..5cbb317 100644 --- a/arch/x86/kernel/mpparse.c +++ b/arch/x86/kernel/mpparse.c @@ -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; } -- 2.7.4