From 47997d756aa2a84ab577e1b0383cc12d582fc69c Mon Sep 17 00:00:00 2001 From: Matt Fleming Date: Wed, 21 Sep 2011 16:08:03 +0200 Subject: x86/rtc: Don't recursively acquire rtc_lock A deadlock was introduced on x86 in commit ef68c8f87ed1 ("x86: Serialize EFI time accesses on rtc_lock") because efi_get_time() and friends can be called with rtc_lock already held by read_persistent_time(), e.g.: timekeeping_init() read_persistent_clock() <-- acquire rtc_lock efi_get_time() phys_efi_get_time() <-- acquire rtc_lock To fix this let's push the locking down into the get_wallclock() and set_wallclock() implementations. Only the clock implementations that access the x86 RTC directly need to acquire rtc_lock, so it makes sense to push the locking down into the rtc, vrtc and efi code. The virtualization implementations don't require rtc_lock to be held because they provide their own serialization. Signed-off-by: Matt Fleming Acked-by: Jan Beulich Acked-by: Avi Kivity [for the virtualization aspect] Cc: "H. Peter Anvin" Cc: Zhang Rui Cc: Josh Boyer Signed-off-by: Andrew Morton Signed-off-by: Thomas Gleixner Signed-off-by: Ingo Molnar --- arch/x86/kernel/rtc.c | 23 ++++++++++++----------- arch/x86/platform/mrst/vrtc.c | 9 +++++++++ 2 files changed, 21 insertions(+), 11 deletions(-) (limited to 'arch/x86') diff --git a/arch/x86/kernel/rtc.c b/arch/x86/kernel/rtc.c index 3f2ad2640d8..ccdbc16b894 100644 --- a/arch/x86/kernel/rtc.c +++ b/arch/x86/kernel/rtc.c @@ -42,8 +42,11 @@ int mach_set_rtc_mmss(unsigned long nowtime) { int real_seconds, real_minutes, cmos_minutes; unsigned char save_control, save_freq_select; + unsigned long flags; int retval = 0; + spin_lock_irqsave(&rtc_lock, flags); + /* tell the clock it's being set */ save_control = CMOS_READ(RTC_CONTROL); CMOS_WRITE((save_control|RTC_SET), RTC_CONTROL); @@ -93,12 +96,17 @@ int mach_set_rtc_mmss(unsigned long nowtime) CMOS_WRITE(save_control, RTC_CONTROL); CMOS_WRITE(save_freq_select, RTC_FREQ_SELECT); + spin_unlock_irqrestore(&rtc_lock, flags); + return retval; } unsigned long mach_get_cmos_time(void) { unsigned int status, year, mon, day, hour, min, sec, century = 0; + unsigned long flags; + + spin_lock_irqsave(&rtc_lock, flags); /* * If UIP is clear, then we have >= 244 microseconds before @@ -125,6 +133,8 @@ unsigned long mach_get_cmos_time(void) status = CMOS_READ(RTC_CONTROL); WARN_ON_ONCE(RTC_ALWAYS_BCD && (status & RTC_DM_BINARY)); + spin_unlock_irqrestore(&rtc_lock, flags); + if (RTC_ALWAYS_BCD || !(status & RTC_DM_BINARY)) { sec = bcd2bin(sec); min = bcd2bin(min); @@ -169,24 +179,15 @@ EXPORT_SYMBOL(rtc_cmos_write); int update_persistent_clock(struct timespec now) { - unsigned long flags; - int retval; - - spin_lock_irqsave(&rtc_lock, flags); - retval = x86_platform.set_wallclock(now.tv_sec); - spin_unlock_irqrestore(&rtc_lock, flags); - - return retval; + return x86_platform.set_wallclock(now.tv_sec); } /* not static: needed by APM */ void read_persistent_clock(struct timespec *ts) { - unsigned long retval, flags; + unsigned long retval; - spin_lock_irqsave(&rtc_lock, flags); retval = x86_platform.get_wallclock(); - spin_unlock_irqrestore(&rtc_lock, flags); ts->tv_sec = retval; ts->tv_nsec = 0; diff --git a/arch/x86/platform/mrst/vrtc.c b/arch/x86/platform/mrst/vrtc.c index 73d70d65e76..6d5dbcdd444 100644 --- a/arch/x86/platform/mrst/vrtc.c +++ b/arch/x86/platform/mrst/vrtc.c @@ -58,8 +58,11 @@ EXPORT_SYMBOL_GPL(vrtc_cmos_write); unsigned long vrtc_get_time(void) { u8 sec, min, hour, mday, mon; + unsigned long flags; u32 year; + spin_lock_irqsave(&rtc_lock, flags); + while ((vrtc_cmos_read(RTC_FREQ_SELECT) & RTC_UIP)) cpu_relax(); @@ -70,6 +73,8 @@ unsigned long vrtc_get_time(void) mon = vrtc_cmos_read(RTC_MONTH); year = vrtc_cmos_read(RTC_YEAR); + spin_unlock_irqrestore(&rtc_lock, flags); + /* vRTC YEAR reg contains the offset to 1960 */ year += 1960; @@ -83,8 +88,10 @@ unsigned long vrtc_get_time(void) int vrtc_set_mmss(unsigned long nowtime) { int real_sec, real_min; + unsigned long flags; int vrtc_min; + spin_lock_irqsave(&rtc_lock, flags); vrtc_min = vrtc_cmos_read(RTC_MINUTES); real_sec = nowtime % 60; @@ -95,6 +102,8 @@ int vrtc_set_mmss(unsigned long nowtime) vrtc_cmos_write(real_sec, RTC_SECONDS); vrtc_cmos_write(real_min, RTC_MINUTES); + spin_unlock_irqrestore(&rtc_lock, flags); + return 0; } -- cgit v1.2.3-18-g5258 From 41bc3186b3c92a4ca05e2aa14bb6272fb491e679 Mon Sep 17 00:00:00 2001 From: Zhao Jin Date: Mon, 19 Sep 2011 12:19:51 +0800 Subject: KVM: MMU: fix incorrect return of spte __update_clear_spte_slow should return original spte while the current code returns low half of original spte combined with high half of new spte. Signed-off-by: Zhao Jin Reviewed-by: Xiao Guangrong Signed-off-by: Marcelo Tosatti --- arch/x86/kvm/mmu.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'arch/x86') diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c index 1c5b69373a0..8e8da7960db 100644 --- a/arch/x86/kvm/mmu.c +++ b/arch/x86/kvm/mmu.c @@ -400,7 +400,8 @@ static u64 __update_clear_spte_slow(u64 *sptep, u64 spte) /* xchg acts as a barrier before the setting of the high bits */ orig.spte_low = xchg(&ssptep->spte_low, sspte.spte_low); - orig.spte_high = ssptep->spte_high = sspte.spte_high; + orig.spte_high = ssptep->spte_high; + ssptep->spte_high = sspte.spte_high; count_spte_clear(sptep, spte); return orig.spte; -- cgit v1.2.3-18-g5258 From 9be3be1f153e90ea4e1e5b6ed1d72a73d44318d1 Mon Sep 17 00:00:00 2001 From: Avi Kivity Date: Tue, 13 Sep 2011 10:45:38 +0300 Subject: KVM: x86 emulator: fix Src2CL decode Src2CL decode (used for double width shifts) erronously decodes only bit 3 of %rcx, instead of bits 7:0. Fix by decoding %cl in its entirety. Signed-off-by: Avi Kivity Signed-off-by: Marcelo Tosatti --- arch/x86/kvm/emulate.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'arch/x86') diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c index 6f08bc940fa..8b4cc5f067d 100644 --- a/arch/x86/kvm/emulate.c +++ b/arch/x86/kvm/emulate.c @@ -3603,7 +3603,7 @@ done_prefixes: break; case Src2CL: ctxt->src2.bytes = 1; - ctxt->src2.val = ctxt->regs[VCPU_REGS_RCX] & 0x8; + ctxt->src2.val = ctxt->regs[VCPU_REGS_RCX] & 0xff; break; case Src2ImmByte: rc = decode_imm(ctxt, &ctxt->src2, 1, true); -- cgit v1.2.3-18-g5258 From 29cf7a30f8a0ce4af2406d93d5a332099be26923 Mon Sep 17 00:00:00 2001 From: Paul Menzel Date: Wed, 31 Aug 2011 17:07:10 +0200 Subject: x86/PCI: use host bridge _CRS info on ASUS M2V-MX SE In summary, this DMI quirk uses the _CRS info by default for the ASUS M2V-MX SE by turning on `pci=use_crs` and is similar to the quirk added by commit 2491762cfb47 ("x86/PCI: use host bridge _CRS info on ASRock ALiveSATA2-GLAN") whose commit message should be read for further information. Since commit 3e3da00c01d0 ("x86/pci: AMD one chain system to use pci read out res") Linux gives the following oops: parport0: PC-style at 0x378, irq 7 [PCSPP,TRISTATE] HDA Intel 0000:20:01.0: PCI INT A -> GSI 17 (level, low) -> IRQ 17 HDA Intel 0000:20:01.0: setting latency timer to 64 BUG: unable to handle kernel paging request at ffffc90011c08000 IP: [] azx_probe+0x3ad/0x86b [snd_hda_intel] PGD 13781a067 PUD 13781b067 PMD 1300ba067 PTE 800000fd00000173 Oops: 0009 [#1] SMP last sysfs file: /sys/module/snd_pcm/initstate CPU 0 Modules linked in: snd_hda_intel(+) snd_hda_codec snd_hwdep snd_pcm_oss snd_mixer_oss snd_pcm snd_seq_midi snd_rawmidi snd_seq_midi_event tpm_tis tpm snd_seq tpm_bios psmouse parport_pc snd_timer snd_seq_device parport processor evdev snd i2c_viapro thermal_sys amd64_edac_mod k8temp i2c_core soundcore shpchp pcspkr serio_raw asus_atk0110 pci_hotplug edac_core button snd_page_alloc edac_mce_amd ext3 jbd mbcache sha256_generic cryptd aes_x86_64 aes_generic cbc dm_crypt dm_mod raid1 md_mod usbhid hid sg sd_mod crc_t10dif sr_mod cdrom ata_generic uhci_hcd sata_via pata_via libata ehci_hcd usbcore scsi_mod via_rhine mii nls_base [last unloaded: scsi_wait_scan] Pid: 1153, comm: work_for_cpu Not tainted 2.6.37-1-amd64 #1 M2V-MX SE/System Product Name RIP: 0010:[] [] azx_probe+0x3ad/0x86b [snd_hda_intel] RSP: 0018:ffff88013153fe50 EFLAGS: 00010286 RAX: ffffc90011c08000 RBX: ffff88013029ec00 RCX: 0000000000000006 RDX: 0000000000000000 RSI: 0000000000000246 RDI: 0000000000000246 RBP: ffff88013341d000 R08: 0000000000000000 R09: 0000000000000040 R10: 0000000000000286 R11: 0000000000003731 R12: ffff88013029c400 R13: 0000000000000000 R14: 0000000000000000 R15: ffff88013341d090 FS: 0000000000000000(0000) GS:ffff8800bfc00000(0000) knlGS:00000000f7610ab0 CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b CR2: ffffc90011c08000 CR3: 0000000132f57000 CR4: 00000000000006f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Process work_for_cpu (pid: 1153, threadinfo ffff88013153e000, task ffff8801303c86c0) Stack: 0000000000000005 ffffffff8123ad65 00000000000136c0 ffff88013029c400 ffff8801303c8998 ffff88013341d000 ffff88013341d090 ffff8801322d9dc8 ffff88013341d208 0000000000000000 0000000000000000 ffffffff811ad232 Call Trace: [] ? __pm_runtime_set_status+0x162/0x186 [] ? local_pci_probe+0x49/0x92 [] ? do_work_for_cpu+0x0/0x1b [] ? do_work_for_cpu+0x0/0x1b [] ? do_work_for_cpu+0xb/0x1b [] ? kthread+0x7a/0x82 [] ? kernel_thread_helper+0x4/0x10 [] ? kthread+0x0/0x82 [] ? kernel_thread_helper+0x0/0x10 Code: f4 01 00 00 ef 31 f6 48 89 df e8 29 dd ff ff 85 c0 0f 88 2b 03 00 00 48 89 ef e8 b4 39 c3 e0 8b 7b 40 e8 fc 9d b1 e0 48 8b 43 38 <66> 8b 10 66 89 14 24 8b 43 14 83 e8 03 83 f8 01 77 32 31 d2 be RIP [] azx_probe+0x3ad/0x86b [snd_hda_intel] RSP CR2: ffffc90011c08000 ---[ end trace 8d1f3ebc136437fd ]--- Trusting the ACPI _CRS information (`pci=use_crs`) fixes this problem. $ dmesg | grep -i crs # with the quirk PCI: Using host bridge windows from ACPI; if necessary, use "pci=nocrs" and report a bug The match has to be against the DMI board entries though since the vendor entries are not populated. DMI: System manufacturer System Product Name/M2V-MX SE, BIOS 0304 10/30/2007 This quirk should be removed when `pci=use_crs` is enabled for machines from 2006 or earlier or some other solution is implemented. Using coreboot [1] with this board the problem does not exist but this quirk also does not affect it either. To be safe though the check is tightened to only take effect when the BIOS from American Megatrends is used. 15:13 < ruik> but coreboot does not need that 15:13 < ruik> because i have there only one root bus 15:13 < ruik> the audio is behind a bridge $ sudo dmidecode BIOS Information Vendor: American Megatrends Inc. Version: 0304 Release Date: 10/30/2007 [1] http://www.coreboot.org/ Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=30552 Cc: stable@kernel.org (2.6.34) Cc: Thomas Gleixner Cc: Ingo Molnar Cc: H. Peter Anvin Cc: x86@kernel.org Signed-off-by: Paul Menzel Signed-off-by: Bjorn Helgaas Acked-by: Jesse Barnes Signed-off-by: Linus Torvalds --- arch/x86/pci/acpi.c | 11 +++++++++++ 1 file changed, 11 insertions(+) (limited to 'arch/x86') diff --git a/arch/x86/pci/acpi.c b/arch/x86/pci/acpi.c index 039d91315bc..404f21a3ff9 100644 --- a/arch/x86/pci/acpi.c +++ b/arch/x86/pci/acpi.c @@ -43,6 +43,17 @@ static const struct dmi_system_id pci_use_crs_table[] __initconst = { DMI_MATCH(DMI_PRODUCT_NAME, "ALiveSATA2-GLAN"), }, }, + /* https://bugzilla.kernel.org/show_bug.cgi?id=30552 */ + /* 2006 AMD HT/VIA system with two host bridges */ + { + .callback = set_use_crs, + .ident = "ASUS M2V-MX SE", + .matches = { + DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTeK Computer INC."), + DMI_MATCH(DMI_BOARD_NAME, "M2V-MX SE"), + DMI_MATCH(DMI_BIOS_VENDOR, "American Megatrends Inc."), + }, + }, {} }; -- cgit v1.2.3-18-g5258