linux/arch/x86
Xiaochen Shen c8eafe1495 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: 94457b36e8 ("x86/intel_rdt: Add diagnostics when writing the cpus file")
Fixes: cfd0f34e4c ("x86/intel_rdt: Add diagnostics when making directories")
Signed-off-by: Xiaochen Shen <xiaochen.shen@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Reviewed-by: Fenghua Yu <fenghua.yu@intel.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: pei.p.jia@intel.com
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: x86-ml <x86@kernel.org>
Link: https://lkml.kernel.org/r/1573079796-11713-1-git-send-email-xiaochen.shen@intel.com
2019-11-13 12:34:44 +01:00
..
boot x86, efi: Never relocate kernel below lowest acceptable address 2019-10-31 09:40:19 +01:00
configs x86/defconfigs: Remove useless UEVENT_HELPER_PATH 2019-06-21 19:22:08 +02:00
crypto crypto: x86/aes-ni - use AES library instead of single-use AES cipher 2019-09-09 23:48:41 +10:00
entry Kbuild updates for v5.4 2019-09-20 08:36:47 -07:00
events perf/x86/uncore: Fix event group support 2019-10-28 11:02:01 +01:00
hyperv x86/hyperv: Make vapic support x2apic mode 2019-10-15 10:57:09 +02:00
ia32 clone: fix CLONE_PIDFD support 2019-07-14 20:36:12 +02:00
include Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2019-10-27 07:14:40 -04:00
kernel x86/resctrl: Fix potential lockdep warning 2019-11-13 12:34:44 +01:00
kvm KVM: vmx, svm: always run with EFER.NXE=1 when shadow paging is active 2019-10-31 12:13:44 +01:00
lib x86/asm: Fix MWAITX C-state hint value 2019-10-08 13:25:24 +02:00
math-emu x86/fpu/math-emu: Address fallthrough warnings 2019-08-12 20:35:05 +02:00
mm Merge branch 'next-lockdown' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security 2019-09-28 08:14:15 -07:00
net bpf: fix x64 JIT code generation for jmp to 1st insn 2019-08-01 13:12:09 -07:00
oprofile
pci dma-mapping updates for 5.4: 2019-09-19 13:27:23 -07:00
platform efi/x86: Do not clean dummy variable in kexec path 2019-10-07 15:24:36 +02:00
power Merge branch 'x86-apic-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2019-09-17 12:04:39 -07:00
purgatory Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2019-09-28 13:37:41 -07:00
ras
realmode x86/realmode: Remove trampoline_status 2019-07-22 11:30:18 +02:00
tools Merge branch 'x86-paravirt-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2019-07-08 17:34:44 -07:00
um um: Use real DMA barriers 2019-09-15 21:37:14 +02:00
video
xen xen: patch for 5.4-rc5 2019-10-26 06:32:12 -04:00
.gitignore
Kbuild
Kconfig Merge branch 'next-lockdown' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security 2019-09-28 08:14:15 -07:00
Kconfig.cpu x86/cpu: Create Zhaoxin processors architecture support file 2019-06-22 11:45:57 +02:00
Kconfig.debug x86, perf: Fix the dependency of the x86 insn decoder selftest 2019-09-02 20:05:58 +02:00
Makefile x86/build: Add -Wnoaddress-of-packed-member to REALMODE_CFLAGS, to silence GCC9 build warning 2019-08-28 17:31:31 +02:00
Makefile_32.cpu
Makefile.um