BMC/Intel-BMC/linux.git/arch/powerpc/kernel/mce_power.c, branch dev-5.2

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 156

2019-05-30T18:26:35+00:00

Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license as published by the free software foundation either version 2 of the license or at your option any later version this program is distributed in the hope that it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details you should have received a copy of the gnu general public license along with this program if not write to the free software foundation inc 59 temple place suite 330 boston ma 02111 1307 usa extracted by the scancode license scanner the SPDX license identifier GPL-2.0-or-later has been chosen to replace the boilerplate/reference in 1334 file(s). Signed-off-by: Thomas Gleixner Reviewed-by: Allison Randal Reviewed-by: Richard Fontana Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190527070033.113240726@linutronix.de Signed-off-by: Greg Kroah-Hartman

powerpc/powernv/mce: Print additional information about MCE error.

2019-05-01T12:23:20+00:00

Print more information about MCE error whether it is an hardware or software error. Some of the MCE errors can be easily categorized as hardware or software errors e.g. UEs are due to hardware error, where as error triggered due to invalid usage of tlbie is a pure software bug. But not all the MCE errors can be easily categorize into either software or hardware. There are errors like multihit errors which are usually result of a software bug, but in some rare cases a hardware failure can cause a multihit error. In past, we have seen case where after replacing faulty chip, multihit errors stopped occurring. Same with parity errors, which are usually due to faulty hardware but there are chances where multihit can also cause an parity error. Such errors are difficult to determine what really caused it. Hence this patch classifies MCE errors into following four categorize: 1. Hardware error: UE and Link timeout failure errors. 2. Probable hardware error (some chance of software cause) SLB/ERAT/TLB Parity errors. 3. Software error Invalid tlbie form. 4. Probable software error (some chance of hardware cause) SLB/ERAT/TLB Multihit errors. Sample output: MCE: CPU80: machine check (Warning) Guest SLB Multihit DAR: 000001001b6e0320 [Recovered] MCE: CPU80: PID: 24765 Comm: qemu-system-ppc Guest NIP: [00007fffa309dc60] MCE: CPU80: Probable Software error (some chance of hardware cause) Signed-off-by: Mahesh Salgaonkar Signed-off-by: Michael Ellerman

powerpc/powernv/mce: Print correct severity for MCE error.

2019-05-01T12:22:51+00:00

Currently all machine check errors are printed as severe errors which isn't correct. Print soft errors as warning instead of severe errors. Signed-off-by: Mahesh Salgaonkar Signed-off-by: Michael Ellerman

powerpc/pseries: hwpoison the pages upon hitting UE

2019-04-20T12:02:35+00:00

Add support to hwpoison the pages upon hitting machine check exception. This patch queues the address where UE is hit to percpu array and schedules work to plumb it into memory poison infrastructure. Reviewed-by: Mahesh Salgaonkar Signed-off-by: Ganesh Goudar [mpe: Combine #ifdefs, drop PPC_BIT8(), and empty inline stub] Signed-off-by: Michael Ellerman

powerpc/64s/hash: Do not use PPC_INVALIDATE_ERAT on CPUs before POWER9

2018-10-04T13:16:53+00:00

PPC_INVALIDATE_ERAT is slbia IH=7 which is a new variant introduced with POWER9, and the result is undefined on earlier CPUs. Commits 7b9f71f974 ("powerpc/64s: POWER9 machine check handler") and d4748276ae ("powerpc/64s: Improve local TLB flush for boot and MCE on POWER9") caused POWER7/8 code to use this instruction. Remove it. An ERAT flush can be made by invalidatig the SLB, but before POWER9 that requires a flush and rebolt. Fixes: 7b9f71f974 ("powerpc/64s: POWER9 machine check handler") Fixes: d4748276ae ("powerpc/64s: Improve local TLB flush for boot and MCE on POWER9") Cc: stable@vger.kernel.org # v4.11+ Signed-off-by: Nicholas Piggin Signed-off-by: Michael Ellerman

powerpc/pseries: Flush SLB contents on SLB MCE errors.

2018-09-19T11:59:22+00:00

On pseries, as of today system crashes if we get a machine check exceptions due to SLB errors. These are soft errors and can be fixed by flushing the SLBs so the kernel can continue to function instead of system crash. We do this in real mode before turning on MMU. Otherwise we would run into nested machine checks. This patch now fetches the rtas error log in real mode and flushes the SLBs on SLB/ERAT errors. Signed-off-by: Mahesh Salgaonkar Signed-off-by: Michal Suchanek Reviewed-by: Nicholas Piggin Signed-off-by: Michael Ellerman

powerpc/64s: move machine check SLB flushing to mm/slb.c

2018-08-10T12:12:39+00:00

The machine check code that flushes and restores bolted segments in real mode belongs in mm/slb.c. This will also be used by pseries machine check and idle code in future changes. Signed-off-by: Nicholas Piggin Signed-off-by: Michael Ellerman

powerpc/64s: Report SLB multi-hit rather than parity error

2018-07-12T11:08:10+00:00

When we take an SLB multi-hit on bare metal, we see both the multi-hit and parity error bits set in DSISR. The user manuals indicates this is expected to always happen on Power8, whereas on Power9 it says a multi-hit will "usually" also cause a parity error. We decide what to do based on the various error tables in mce_power.c, and because we process them in order and only report the first, we currently always report a parity error but not the multi-hit, eg: Severe Machine check interrupt [Recovered] Initiator: CPU Error type: SLB [Parity] Effective address: c000000ffffd4300 Although this is correct, it leaves the user wondering why they got a parity error. It would be clearer instead if we reported the multi-hit because that is more likely to be simply a software bug, whereas a true parity error is possibly an indication of a bad core. We can do that simply by reordering the error tables so that multi-hit appears before parity. That doesn't affect the error recovery at all, because we flush the SLB either way. Signed-off-by: Michael Ellerman Reviewed-by: Nicholas Piggin Signed-off-by: Michael Ellerman

powerpc/mce: Fix a bug where mce loops on memory UE.

2018-04-24T03:54:51+00:00

The current code extracts the physical address for UE errors and then hooks it up into memory failure infrastructure. On successful extraction of physical address it wrongly sets "handled = 1" which means this UE error has been recovered. Since MCE handler gets return value as handled = 1, it assumes that error has been recovered and goes back to same NIP. This causes MCE interrupt again and again in a loop leading to hard lockup. Also, initialize phys_addr to ULONG_MAX so that we don't end up queuing undesired page to hwpoison. Without this patch we see: Severe Machine check interrupt [Recovered] NIP: [000000001002588c] PID: 7109 Comm: find Initiator: CPU Error type: UE [Load/Store] Effective address: 00007fffd2755940 Physical address: 000020181a080000 ... Severe Machine check interrupt [Recovered] NIP: [000000001002588c] PID: 7109 Comm: find Initiator: CPU Error type: UE [Load/Store] Effective address: 00007fffd2755940 Physical address: 000020181a080000 Severe Machine check interrupt [Recovered] NIP: [000000001002588c] PID: 7109 Comm: find Initiator: CPU Error type: UE [Load/Store] Effective address: 00007fffd2755940 Physical address: 000020181a080000 Memory failure: 0x20181a08: recovery action for dirty LRU page: Recovered Memory failure: 0x20181a08: already hardware poisoned Memory failure: 0x20181a08: already hardware poisoned Memory failure: 0x20181a08: already hardware poisoned Memory failure: 0x20181a08: already hardware poisoned Memory failure: 0x20181a08: already hardware poisoned Memory failure: 0x20181a08: already hardware poisoned ... Watchdog CPU:38 Hard LOCKUP After this patch we see: Severe Machine check interrupt [Not recovered] NIP: [00007fffaae585f4] PID: 7168 Comm: find Initiator: CPU Error type: UE [Load/Store] Effective address: 00007fffaafe28ac Physical address: 00002017c0bd0000 find[7168]: unhandled signal 7 at 00007fffaae585f4 nip 00007fffaae585f4 lr 00007fffaae585e0 code 4 Memory failure: 0x2017c0bd: recovery action for dirty LRU page: Recovered Fixes: 01eaac2b0591 ("powerpc/mce: Hookup ierror (instruction) UE errors") Fixes: ba41e1e1ccb9 ("powerpc/mce: Hookup derror (load/store) UE errors") Cc: stable@vger.kernel.org # v4.15+ Signed-off-by: Mahesh Salgaonkar Signed-off-by: Balbir Singh Reviewed-by: Balbir Singh Signed-off-by: Michael Ellerman

powerpc/64s: Improve local TLB flush for boot and MCE on POWER9

2018-01-17T13:40:31+00:00

There are several cases outside the normal address space management where a CPU's entire local TLB is to be flushed: 1. Booting the kernel, in case something has left stale entries in the TLB (e.g., kexec). 2. Machine check, to clean corrupted TLB entries. One other place where the TLB is flushed, is waking from deep idle states. The flush is a side-effect of calling ->cpu_restore with the intention of re-setting various SPRs. The flush itself is unnecessary because in the first case, the TLB should not acquire new corrupted TLB entries as part of sleep/wake (though they may be lost). This type of TLB flush is coded inflexibly, several times for each CPU type, and they have a number of problems with ISA v3.0B: - The current radix mode of the MMU is not taken into account, it is always done as a hash flushn For IS=2 (LPID-matching flush from host) and IS=3 with HV=0 (guest kernel flush), tlbie(l) is undefined if the R field does not match the current radix mode. - ISA v3.0B hash must flush the partition and process table caches as well. - ISA v3.0B radix must flush partition and process scoped translations, partition and process table caches, and also the page walk cache. So consolidate the flushing code and implement it in C and inline asm under the mm/ directory with the rest of the flush code. Add ISA v3.0B cases for radix and hash, and use the radix flush in radix environment. Provide a way for IS=2 (LPID flush) to specify the radix mode of the partition. Have KVM pass in the radix mode of the guest. Take out the flushes from early cputable/dt_cpu_ftrs detection hooks, and move it later in the boot process after, the MMU registers are set up and before relocation is first turned on. The TLB flush is no longer called when restoring from deep idle states. This was not be done as a separate step because booting secondaries uses the same cpu_restore as idle restore, which needs the TLB flush. Signed-off-by: Nicholas Piggin Signed-off-by: Michael Ellerman