lwn.git/drivers/xen/xen-acpi-processor.c, branch docs-6.4-2

xen: Fix implicit type conversion

2021-11-02T12:45:44+00:00

The variable 'i' is defined as UINT. However, in the for_each_possible_cpu its value is assigned to -1. That doesn't make sense and in the cpumask_next() it is implicitly type converted to INT. It is universally accepted that the implicit type conversion is terrible. Also, having the good programming custom will set an example for others. Thus, it might be better to change the definition of 'i' from UINT to INT. [boris: fixed commit message formatting] Fixes: 3fac10145b76 ("xen: Re-upload processor PM data to hypervisor after S3 resume (v2)") Signed-off-by: Jiasheng Jiang Link: https://lore.kernel.org/r/1635233531-2437704-1-git-send-email-jiasheng@iscas.ac.cn Reviewed-by: Juergen Gross Reviewed-by: Jiamei Xie Signed-off-by: Boris Ostrovsky

xen: Replace lkml.org links with lore

2021-02-23T16:08:07+00:00

As started by commit 05a5f51ca566 ("Documentation: Replace lkml.org links with lore"), replace lkml.org links with lore to better use a single source that's more likely to stay available long-term. Signed-off-by: Kees Cook Reviewed-by: Boris Ostrovsky Link: https://lore.kernel.org/r/20210210234618.2734785-1-keescook@chromium.org Signed-off-by: Boris Ostrovsky

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 288

2019-06-05T15:36:37+00:00

Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms and conditions of the gnu general public license version 2 as published by the free software foundation this program is distributed in the hope 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 extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 263 file(s). Signed-off-by: Thomas Gleixner Reviewed-by: Allison Randal Reviewed-by: Alexios Zavras Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190529141901.208660670@linutronix.de Signed-off-by: Greg Kroah-Hartman

xen/ACPI: Switch to bitmap_zalloc()

2019-03-04T14:04:39+00:00

Switch to bitmap_zalloc() to show clearly what we are allocating. Besides that it returns pointer of bitmap type instead of opaque void *. Signed-off-by: Andy Shevchenko Reviewed-by: Juergen Gross Signed-off-by: Juergen Gross

xen/ACPI: don't upload Px/Cx data for disabled processors

2018-08-20T18:46:18+00:00

This is unnecessary and triggers a warning in the hypervisor. Often systems have more processor entries in their ACPI tables than are actually installed/active. The ACPI_STA_DEVICE_PRESENT bit cannot be reliably used, but the ACPI_MADT_ENABLED bit can. In order to not introduce new functions in the main ACPI processor driver code, simply use acpi_get_phys_id(), which does more than we need, but which checks the MADT enabled bit in the process. Any CPU for which we can't determine the APIC ID is unlikely to work properly anyway, so the extra checks done by acpi_get_phys_id() should do no harm. Signed-off-by: Jan Beulich Reviewed-by: Juergen Gross Acked-by: Rafael J. Wysocki Signed-off-by: Boris Ostrovsky

xen/acpi: off by one in read_acpi_id()

2018-03-30T15:30:13+00:00

If acpi_id is == nr_acpi_bits, then we access one element beyond the end of the acpi_psd[] array or we set one bit beyond the end of the bit map when we do __set_bit(acpi_id, acpi_id_present); Fixes: 59a568029181 ("xen/acpi-processor: C and P-state driver that uploads said data to hypervisor.") Signed-off-by: Dan Carpenter Reviewed-by: Joao Martins Reviewed-by: Juergen Gross Signed-off-by: Boris Ostrovsky

xen/acpi: upload _PSD info for non Dom0 CPUs too

2018-03-21T12:29:13+00:00

All uploaded PM data from non-dom0 CPUs takes the info from vCPU 0 and changing only the acpi_id. For processors which P-state coordination type is HW_ALL (0xFD) it is OK to upload bogus P-state dependency information (_PSD), because Xen will ignore any cpufreq domains created for past CPUs. Albeit for platforms which expose coordination types as SW_ANY or SW_ALL, this will have some unintended side effects. Effectively, it will look at the P-state domain existence and *if it already exists* it will skip the acpi-cpufreq initialization and thus inherit the policy from the first CPU in the cpufreq domain. This will finally lead to the original cpu not changing target freq to P0 other than the first in the domain. Which will make turbo boost not getting enabled (e.g. for 'performance' governor) for all cpus. This patch fixes that, by also evaluating _PSD when we enumerate all ACPI processors and thus always uploading the correct info to Xen. We export acpi_processor_get_psd() for that this purpose, but change signature to not assume an existent of acpi_processor given that ACPI isn't creating an acpi_processor for non-dom0 CPUs. Signed-off-by: Joao Martins Reviewed-by: Boris Ostrovsky Acked-by: Rafael J. Wysocki Signed-off-by: Boris Ostrovsky

xen/acpi: upload PM state from init-domain to Xen

2017-03-23T16:00:02+00:00

This was broken in commit cd979883b9ed ("xen/acpi-processor: fix enabling interrupts on syscore_resume"). do_suspend (from xen/manage.c) and thus xen_resume_notifier never get called on the initial-domain at resume (it is if running as guest.) The rationale for the breaking change was that upload_pm_data() potentially does blocking work in syscore_resume(). This patch addresses the original issue by scheduling upload_pm_data() to execute in workqueue context. Cc: Stanislaw Gruszka Cc: stable@vger.kernel.org Based-on-patch-by: Konrad Wilk Reviewed-by: Konrad Rzeszutek Wilk Reviewed-by: Stanislaw Gruszka Signed-off-by: Ankur Arora Signed-off-by: Boris Ostrovsky

xen/acpi: Replace hard coded "ACPI0007"

2017-03-23T13:42:15+00:00

Replace hard coded "ACPI0007" with ACPI_PROCESSOR_DEVICE_HID Reviewed-by: Konrad Rzeszutek Wilk Signed-off-by: Ankur Arora Signed-off-by: Boris Ostrovsky

xen/acpi: allow xen-acpi-processor driver to load on Xen 4.7

2016-07-08T13:53:13+00:00

As of Xen 4.7 PV CPUID doesn't expose either of CPUID[1].ECX[7] and CPUID[0x80000007].EDX[7] anymore, causing the driver to fail to load on both Intel and AMD systems. Doing any kind of hardware capability checks in the driver as a prerequisite was wrong anyway: With the hypervisor being in charge, all such checking should be done by it. If ACPI data gets uploaded despite some missing capability, the hypervisor is free to ignore part or all of that data. Ditch the entire check_prereq() function, and do the only valid check (xen_initial_domain()) in the caller in its place. Signed-off-by: Jan Beulich Cc: Signed-off-by: David Vrabel