From fc5db58539b49351e76f19817ed1102bf7c712d0 Mon Sep 17 00:00:00 2001 From: Kai-Heng Feng Date: Wed, 16 Oct 2019 18:38:16 +0800 Subject: x86/quirks: Disable HPET on Intel Coffe Lake platforms Some Coffee Lake platforms have a skewed HPET timer once the SoCs entered PC10, which in consequence marks TSC as unstable because HPET is used as watchdog clocksource for TSC. Harry Pan tried to work around it in the clocksource watchdog code [1] thereby creating a circular dependency between HPET and TSC. This also ignores the fact, that HPET is not only unsuitable as watchdog clocksource on these systems, it becomes unusable in general. Disable HPET on affected platforms. Suggested-by: Feng Tang Signed-off-by: Kai-Heng Feng Signed-off-by: Thomas Gleixner Cc: stable@vger.kernel.org Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=203183 Link: https://lore.kernel.org/lkml/20190516090651.1396-1-harry.pan@intel.com/ [1] Link: https://lkml.kernel.org/r/20191016103816.30650-1-kai.heng.feng@canonical.com --- arch/x86/kernel/early-quirks.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/arch/x86/kernel/early-quirks.c b/arch/x86/kernel/early-quirks.c index 6f6b1d04dadf..4cba91ec8049 100644 --- a/arch/x86/kernel/early-quirks.c +++ b/arch/x86/kernel/early-quirks.c @@ -710,6 +710,8 @@ static struct chipset early_qrk[] __initdata = { */ { PCI_VENDOR_ID_INTEL, 0x0f00, PCI_CLASS_BRIDGE_HOST, PCI_ANY_ID, 0, force_disable_hpet}, + { PCI_VENDOR_ID_INTEL, 0x3ec4, + PCI_CLASS_BRIDGE_HOST, PCI_ANY_ID, 0, force_disable_hpet}, { PCI_VENDOR_ID_BROADCOM, 0x4331, PCI_CLASS_NETWORK_OTHER, PCI_ANY_ID, 0, apple_airport_reset}, {} -- cgit v1.2.3 From c8eafe1495303bfd0eedaa8156b1ee9082ee9642 Mon Sep 17 00:00:00 2001 From: Xiaochen Shen Date: Thu, 7 Nov 2019 06:36:36 +0800 Subject: x86/resctrl: Fix potential lockdep warning rdtgroup_cpus_write() and mkdir_rdt_prepare() call rdtgroup_kn_lock_live() -> kernfs_to_rdtgroup() to get 'rdtgrp', and then call the rdt_last_cmd_{clear,puts,...}() functions which will check if rdtgroup_mutex is held/requires its caller to hold rdtgroup_mutex. But if 'rdtgrp' returned from kernfs_to_rdtgroup() is NULL, rdtgroup_mutex is not held and calling rdt_last_cmd_{clear,puts,...}() will result in a self-incurred, potential lockdep warning. Remove the rdt_last_cmd_{clear,puts,...}() calls in these two paths. Just returning error should be sufficient to report to the user that the entry doesn't exist any more. [ bp: Massage. ] Fixes: 94457b36e8a5 ("x86/intel_rdt: Add diagnostics when writing the cpus file") Fixes: cfd0f34e4cd5 ("x86/intel_rdt: Add diagnostics when making directories") Signed-off-by: Xiaochen Shen Signed-off-by: Borislav Petkov Reviewed-by: Tony Luck Reviewed-by: Fenghua Yu Reviewed-by: Reinette Chatre Cc: "H. Peter Anvin" Cc: Ingo Molnar Cc: pei.p.jia@intel.com Cc: Thomas Gleixner Cc: x86-ml Link: https://lkml.kernel.org/r/1573079796-11713-1-git-send-email-xiaochen.shen@intel.com --- arch/x86/kernel/cpu/resctrl/rdtgroup.c | 4 ---- 1 file changed, 4 deletions(-) diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/resctrl/rdtgroup.c index a46dee8e78db..2e3b06d6bbc6 100644 --- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c +++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c @@ -461,10 +461,8 @@ static ssize_t rdtgroup_cpus_write(struct kernfs_open_file *of, } rdtgrp = rdtgroup_kn_lock_live(of->kn); - rdt_last_cmd_clear(); if (!rdtgrp) { ret = -ENOENT; - rdt_last_cmd_puts("Directory was removed\n"); goto unlock; } @@ -2648,10 +2646,8 @@ static int mkdir_rdt_prepare(struct kernfs_node *parent_kn, int ret; prdtgrp = rdtgroup_kn_lock_live(prgrp_kn); - rdt_last_cmd_clear(); if (!prdtgrp) { ret = -ENODEV; - rdt_last_cmd_puts("Directory was removed\n"); goto out_unlock; } -- cgit v1.2.3