linux-dev/arch/powerpc/kernel/firmware.c, branch linus/master

powerpc: fix unbalanced node refcount in check_kvm_guest()

2021-10-08T13:15:59Z

When check_kvm_guest() succeeds in looking up a /hypervisor OF node, it returns without performing a matching put for the lookup, leaving the node's reference count elevated. Add the necessary call to of_node_put(), rearranging the code slightly to avoid repetition or goto. Fixes: 107c55005fbd ("powerpc/pseries: Add KVM guest doorbell restrictions") Signed-off-by: Nathan Lynch Reviewed-by: Srikar Dronamraju Reviewed-by: Tyrel Datwyler Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20210928124550.132020-1-nathanl@linux.ibm.com

powerpc: Fix is_kvm_guest() / kvm_para_available()

2021-06-25T04:47:19Z

Commit a21d1becaa3f ("powerpc: Reintroduce is_kvm_guest() as a fast-path check") added is_kvm_guest() and changed kvm_para_available() to use it. is_kvm_guest() checks a static key, kvm_guest, and that static key is set in check_kvm_guest(). The problem is check_kvm_guest() is only called on pseries, and even then only in some configurations. That means is_kvm_guest() always returns false on all non-pseries and some pseries depending on configuration. That's a bug. For PR KVM guests this is noticable because they no longer do live patching of themselves, which can be detected by the omission of a message in dmesg such as: KVM: Live patching for a fast VM worked To fix it make check_kvm_guest() an initcall, to ensure it's always called at boot. It needs to be core so that it runs before kvm_guest_init() which is postcore. To be an initcall it needs to return int, where 0 means success, so update that. We still call it manually in pSeries_smp_probe(), because that runs before init calls are run. Fixes: a21d1becaa3f ("powerpc: Reintroduce is_kvm_guest() as a fast-path check") Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20210623130514.2543232-1-mpe@ellerman.id.au

powerpc: Reintroduce is_kvm_guest() as a fast-path check

2020-12-03T14:01:22Z

Introduce a static branch that would be set during boot if the OS happens to be a KVM guest. Subsequent checks to see if we are on KVM will rely on this static branch. This static branch would be used in vcpu_is_preempted() in a subsequent patch. Signed-off-by: Srikar Dronamraju Acked-by: Waiman Long Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20201202050456.164005-4-srikar@linux.vnet.ibm.com

powerpc: Rename is_kvm_guest() to check_kvm_guest()

2020-12-03T14:01:21Z

We want to reuse the is_kvm_guest() name in a subsequent patch but with a new body. Hence rename is_kvm_guest() to check_kvm_guest(). No additional changes. Signed-off-by: Srikar Dronamraju Acked-by: Waiman Long Signed-off-by: kernel test robot # int -> bool fix [mpe: Fold in fix from lkp to use true/false not 0/1] Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20201202050456.164005-3-srikar@linux.vnet.ibm.com

powerpc: Refactor is_kvm_guest() declaration to new header

2020-12-03T14:01:21Z

Only code/declaration movement, in anticipation of doing a KVM-aware vcpu_is_preempted(). No additional changes. Signed-off-by: Srikar Dronamraju Acked-by: Waiman Long Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20201202050456.164005-2-srikar@linux.vnet.ibm.com

powerpc/pseries: Add KVM guest doorbell restrictions

2020-07-29T11:02:10Z

KVM guests have certain restrictions and performance quirks when using doorbells. This patch moves the EPAPR KVM guest test so it can be shared with PSERIES, and uses that in doorbell setup code to apply the KVM guest quirks and improves IPI performance for two cases: - PowerVM guests may now use doorbells even if they are secure. - KVM guests no longer use doorbells if XIVE is available. There is a valid complaint that "KVM guest" is not a very reasonable thing to test for, it's preferable for the hypervisor to advertise particular behaviours to the guest so they could change if the hypervisor implementation or configuration changes. However in this case we were already assuming a KVM guest worst case, so this patch is about containing those quirks. If KVM later advertises fast doorbells, we should test for that and override the quirks. Signed-off-by: Nicholas Piggin Tested-by: Cédric Le Goater Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20200726035155.1424103-4-npiggin@gmail.com

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152

2019-05-30T18:26:32Z

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 extracted by the scancode license scanner the SPDX license identifier GPL-2.0-or-later has been chosen to replace the boilerplate/reference in 3029 file(s). Signed-off-by: Thomas Gleixner Reviewed-by: Allison Randal Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de Signed-off-by: Greg Kroah-Hartman

powerpc: fix implicit use of cache.h in kernel/firmware.c

2011-10-31T23:30:41Z

This file only needs export.h to get EXPORT_SYMBOL, but in doing so, it uncovers an implicit use of linux/cache.h as follows: CC arch/powerpc/kernel/firmware.o arch/powerpc/kernel/firmware.c:20: error: expected '=', ',', ';', 'asm' or '__attribute__' before '__read_mostly' arch/powerpc/kernel/firmware.c:21: error: expected '=', ',', ';', 'asm' or '__attribute__' before '__used' make[2]: *** [arch/powerpc/kernel/firmware.o] Error 1 Signed-off-by: Paul Gortmaker

powerpc: Make powerpc_firmware_features __read_mostly

2010-02-09T02:56:07Z

We use firmware_has_feature quite a lot these days, so it's worth putting powerpc_firmware_features into __read_mostly. Signed-off-by: Anton Blanchard Signed-off-by: Benjamin Herrenschmidt

Remove obsolete #include

2006-06-30T17:25:36Z

Signed-off-by: Jörn Engel Signed-off-by: Adrian Bunk