From f79b1c573cb4dc551919f81ed5797419f6fc1f3a Mon Sep 17 00:00:00 2001 From: Rajneesh Bhardwaj Date: Thu, 29 Mar 2018 20:36:55 +0530 Subject: x86/i8237: Register device based on FADT legacy boot flag MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit From Skylake onwards, the platform controller hub (Sunrisepoint PCH) does not support legacy DMA operations to IO ports 81h-83h, 87h, 89h-8Bh, 8Fh. Currently this driver registers as syscore ops and its resume function is called on every resume from S3. On Skylake and Kabylake, this causes a resume delay of around 100ms due to port IO operations, which is a problem. This change allows to load the driver only when the platform bios explicitly supports such devices or has a cut-off date earlier than 2017 due to the following reasons: - The platforms released before year 2017 have support for the 8237. (except Sunrisepoint PCH e.g. Skylake) - Some of the BIOS that were released for platforms (Skylake, Kabylake) during 2016-17 are buggy. These BIOS do not set/unset the ACPI_FADT_LEGACY_DEVICES field in FADT table properly based on the presence or absence of the DMA device. Very recently, open source system firmware like coreboot started unsetting ACPI_FADT_LEGACY_DEVICES field in FADT table if the 8237 DMA device is not present on the PCH. Please refer to chapter 21 of 6th Generation Intel® Core™ Processor Platform Controller Hub Family: BIOS Specification. Signed-off-by: Rajneesh Bhardwaj Signed-off-by: Anshuman Gupta Signed-off-by: Thomas Gleixner Reviewed-by: Andy Shevchenko Cc: rjw@rjwysocki.net Cc: hpa@zytor.com Cc: Alan Cox Link: https://lkml.kernel.org/r/1522336015-22994-1-git-send-email-anshuman.gupta@intel.com --- arch/x86/include/asm/x86_init.h | 1 + arch/x86/kernel/i8237.c | 25 +++++++++++++++++++++++++ arch/x86/kernel/platform-quirks.c | 7 ++++++- 3 files changed, 32 insertions(+), 1 deletion(-) diff --git a/arch/x86/include/asm/x86_init.h b/arch/x86/include/asm/x86_init.h index ce8b4da07e35..db98e3ab3295 100644 --- a/arch/x86/include/asm/x86_init.h +++ b/arch/x86/include/asm/x86_init.h @@ -301,5 +301,6 @@ extern struct x86_apic_ops x86_apic_ops; extern void x86_early_init_platform_quirks(void); extern void x86_init_noop(void); extern void x86_init_uint_noop(unsigned int unused); +extern bool x86_pnpbios_disabled(void); #endif diff --git a/arch/x86/kernel/i8237.c b/arch/x86/kernel/i8237.c index 8eeaa81de066..0a3e70fd00d6 100644 --- a/arch/x86/kernel/i8237.c +++ b/arch/x86/kernel/i8237.c @@ -9,10 +9,12 @@ * your option) any later version. */ +#include #include #include #include +#include /* * This module just handles suspend/resume issues with the @@ -49,6 +51,29 @@ static struct syscore_ops i8237_syscore_ops = { static int __init i8237A_init_ops(void) { + /* + * From SKL PCH onwards, the legacy DMA device is removed in which the + * I/O ports (81h-83h, 87h, 89h-8Bh, 8Fh) related to it are removed + * as well. All removed ports must return 0xff for a inb() request. + * + * Note: DMA_PAGE_2 (port 0x81) should not be checked for detecting + * the presence of DMA device since it may be used by BIOS to decode + * LPC traffic for POST codes. Original LPC only decodes one byte of + * port 0x80 but some BIOS may choose to enhance PCH LPC port 0x8x + * decoding. + */ + if (dma_inb(DMA_PAGE_0) == 0xFF) + return -ENODEV; + + /* + * It is not required to load this driver as newer SoC may not + * support 8237 DMA or bus mastering from LPC. Platform firmware + * must announce the support for such legacy devices via + * ACPI_FADT_LEGACY_DEVICES field in FADT table. + */ + if (x86_pnpbios_disabled() && dmi_get_bios_year() >= 2017) + return -ENODEV; + register_syscore_ops(&i8237_syscore_ops); return 0; } diff --git a/arch/x86/kernel/platform-quirks.c b/arch/x86/kernel/platform-quirks.c index 235fe6008ac8..b348a672f71d 100644 --- a/arch/x86/kernel/platform-quirks.c +++ b/arch/x86/kernel/platform-quirks.c @@ -33,9 +33,14 @@ void __init x86_early_init_platform_quirks(void) x86_platform.set_legacy_features(); } +bool __init x86_pnpbios_disabled(void) +{ + return x86_platform.legacy.devices.pnpbios == 0; +} + #if defined(CONFIG_PNPBIOS) bool __init arch_pnpbios_disabled(void) { - return x86_platform.legacy.devices.pnpbios == 0; + return x86_pnpbios_disabled(); } #endif -- cgit v1.2.3 From f2173356e26c4da2ddecf9bf3d58a6a2ff56b11d Mon Sep 17 00:00:00 2001 From: Jann Horn Date: Fri, 4 May 2018 19:59:35 +0200 Subject: x86/vdso: Remove unused file commit da861e18eccc ("x86, vdso: Get rid of the fake section mechanism") left this file behind; nothing is using it anymore. Signed-off-by: Jann Horn Signed-off-by: Thomas Gleixner Cc: hpa@zytor.com Cc: luto@amacapital.net Link: https://lkml.kernel.org/r/20180504175935.104085-1-jannh@google.com --- arch/x86/entry/vdso/vdso32/vdso-fakesections.c | 1 - 1 file changed, 1 deletion(-) delete mode 100644 arch/x86/entry/vdso/vdso32/vdso-fakesections.c diff --git a/arch/x86/entry/vdso/vdso32/vdso-fakesections.c b/arch/x86/entry/vdso/vdso32/vdso-fakesections.c deleted file mode 100644 index 541468e25265..000000000000 --- a/arch/x86/entry/vdso/vdso32/vdso-fakesections.c +++ /dev/null @@ -1 +0,0 @@ -#include "../vdso-fakesections.c" -- cgit v1.2.3 From 13a4db9d75ec5dbca4bd6229e149e061ef7a6bf0 Mon Sep 17 00:00:00 2001 From: Andy Shevchenko Date: Tue, 15 May 2018 20:57:59 +0300 Subject: x86/mtrr: Convert to use match_string() helper The helper returns index of the matching string in an array. Replace the open coded array lookup with match_string(). Signed-off-by: Andy Shevchenko Cc: Andrew Morton Cc: Andy Lutomirski Cc: Borislav Petkov Cc: Brian Gerst Cc: Denys Vlasenko Cc: H. Peter Anvin Cc: Josh Poimboeuf Cc: Linus Torvalds Cc: Luis R. Rodriguez Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: Toshi Kani Link: http://lkml.kernel.org/r/20180515175759.89315-1-andriy.shevchenko@linux.intel.com Signed-off-by: Ingo Molnar --- arch/x86/kernel/cpu/mtrr/if.c | 21 ++++++++++----------- 1 file changed, 10 insertions(+), 11 deletions(-) diff --git a/arch/x86/kernel/cpu/mtrr/if.c b/arch/x86/kernel/cpu/mtrr/if.c index 558444b23923..42b4f2f3b557 100644 --- a/arch/x86/kernel/cpu/mtrr/if.c +++ b/arch/x86/kernel/cpu/mtrr/if.c @@ -149,17 +149,16 @@ mtrr_write(struct file *file, const char __user *buf, size_t len, loff_t * ppos) return -EINVAL; ptr = skip_spaces(ptr + 5); - for (i = 0; i < MTRR_NUM_TYPES; ++i) { - if (strcmp(ptr, mtrr_strings[i])) - continue; - base >>= PAGE_SHIFT; - size >>= PAGE_SHIFT; - err = mtrr_add_page((unsigned long)base, (unsigned long)size, i, true); - if (err < 0) - return err; - return len; - } - return -EINVAL; + i = match_string(mtrr_strings, MTRR_NUM_TYPES, ptr); + if (i < 0) + return i; + + base >>= PAGE_SHIFT; + size >>= PAGE_SHIFT; + err = mtrr_add_page((unsigned long)base, (unsigned long)size, i, true); + if (err < 0) + return err; + return len; } static long -- cgit v1.2.3 From 7f8ec5a4f01aa7d03e94a3d99d7b5f9c02d7fe5a Mon Sep 17 00:00:00 2001 From: Andy Shevchenko Date: Tue, 15 May 2018 21:05:35 +0300 Subject: x86/mtrr: Convert to use strncpy_from_user() helper Replace the open coded string fetch from user-space with strncpy_from_user(). Signed-off-by: Andy Shevchenko Cc: Andrew Morton Cc: Andy Lutomirski Cc: Borislav Petkov Cc: Brian Gerst Cc: Denys Vlasenko Cc: H. Peter Anvin Cc: Josh Poimboeuf Cc: Linus Torvalds Cc: Luis R. Rodriguez Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: Toshi Kani Link: http://lkml.kernel.org/r/20180515180535.89703-1-andriy.shevchenko@linux.intel.com Signed-off-by: Ingo Molnar --- arch/x86/kernel/cpu/mtrr/if.c | 12 ++---------- 1 file changed, 2 insertions(+), 10 deletions(-) diff --git a/arch/x86/kernel/cpu/mtrr/if.c b/arch/x86/kernel/cpu/mtrr/if.c index 42b4f2f3b557..c610f47373e4 100644 --- a/arch/x86/kernel/cpu/mtrr/if.c +++ b/arch/x86/kernel/cpu/mtrr/if.c @@ -106,17 +106,9 @@ mtrr_write(struct file *file, const char __user *buf, size_t len, loff_t * ppos) memset(line, 0, LINE_SIZE); - length = len; - length--; - - if (length > LINE_SIZE - 1) - length = LINE_SIZE - 1; - + length = strncpy_from_user(line, buf, LINE_SIZE - 1); if (length < 0) - return -EINVAL; - - if (copy_from_user(line, buf, length)) - return -EFAULT; + return length; linelen = strlen(line); ptr = line + linelen - 1; -- cgit v1.2.3 From ff987fcf011d20c53b3a613edf6e2055ea48e26e Mon Sep 17 00:00:00 2001 From: Scott Wood Date: Thu, 24 May 2018 10:44:20 -0500 Subject: x86/microcode: Make the late update update_lock a raw lock for RT __reload_late() is called from stop_machine context and thus cannot acquire a non-raw spinlock on PREEMPT_RT. Signed-off-by: Scott Wood Signed-off-by: Borislav Petkov Signed-off-by: Thomas Gleixner Acked-by: Thomas Gleixner Cc: Ashok Raj Cc: Clark Williams Cc: Pei Zhang Cc: x86-ml Link: http://lkml.kernel.org/r/20180524154420.24455-1-swood@redhat.com --- arch/x86/kernel/cpu/microcode/core.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/arch/x86/kernel/cpu/microcode/core.c b/arch/x86/kernel/cpu/microcode/core.c index 77e201301528..08286269fd24 100644 --- a/arch/x86/kernel/cpu/microcode/core.c +++ b/arch/x86/kernel/cpu/microcode/core.c @@ -70,7 +70,7 @@ static DEFINE_MUTEX(microcode_mutex); /* * Serialize late loading so that CPUs get updated one-by-one. */ -static DEFINE_SPINLOCK(update_lock); +static DEFINE_RAW_SPINLOCK(update_lock); struct ucode_cpu_info ucode_cpu_info[NR_CPUS]; @@ -560,9 +560,9 @@ static int __reload_late(void *info) if (__wait_for_cpus(&late_cpus_in, NSEC_PER_SEC)) return -1; - spin_lock(&update_lock); + raw_spin_lock(&update_lock); apply_microcode_local(&err); - spin_unlock(&update_lock); + raw_spin_unlock(&update_lock); /* siblings return UCODE_OK because their engine got updated already */ if (err > UCODE_NFOUND) { -- cgit v1.2.3