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2025-03-12x86/resctrl: Move monitor init work to a resctrl init callJames Morse
rdt_get_mon_l3_config() is called from the arch's resctrl_arch_late_init(), and initialises both architecture specific fields, such as hw_res->mon_scale and resctrl filesystem fields by calling dom_data_init(). To separate the filesystem and architecture parts of resctrl, this function needs splitting up. Add resctrl_mon_resource_init() to do the filesystem specific work, and call it from resctrl_init(). This runs later, but is still before the filesystem is mounted and the rmid_ptrs[] array can be used. [ bp: Massage commit message. ] Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com> Reviewed-by: Tony Luck <tony.luck@intel.com> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Reviewed-by: Fenghua Yu <fenghuay@nvidia.com> Reviewed-by: Babu Moger <babu.moger@amd.com> Tested-by: Carl Worth <carl@os.amperecomputing.com> # arm64 Tested-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com> Tested-by: Peter Newman <peternewman@google.com> Tested-by: Amit Singh Tomar <amitsinght@marvell.com> # arm64 Tested-by: Shanker Donthineni <sdonthineni@nvidia.com> # arm64 Tested-by: Babu Moger <babu.moger@amd.com> Link: https://lore.kernel.org/r/20250311183715.16445-17-james.morse@arm.com
2025-03-12x86/resctrl: Move monitor exit work to a resctrl exit callJames Morse
rdt_put_mon_l3_config() is called via the architecture's resctrl_arch_exit() call, and appears to free the rmid_ptrs[] and closid_num_dirty_rmid[] arrays. In reality this code is marked __exit, and is removed by the linker as resctrl can't be built as a module. To separate the filesystem and architecture parts of resctrl, this free()ing work needs to be triggered by the filesystem, as these structures belong to the filesystem code. Rename rdt_put_mon_l3_config() to resctrl_mon_resource_exit() and call it from resctrl_exit(). The kfree() is currently dependent on r->mon_capable. Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com> Reviewed-by: Tony Luck <tony.luck@intel.com> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Reviewed-by: Fenghua Yu <fenghuay@nvidia.com> Reviewed-by: Babu Moger <babu.moger@amd.com> Tested-by: Carl Worth <carl@os.amperecomputing.com> # arm64 Tested-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com> Tested-by: Peter Newman <peternewman@google.com> Tested-by: Amit Singh Tomar <amitsinght@marvell.com> # arm64 Tested-by: Shanker Donthineni <sdonthineni@nvidia.com> # arm64 Tested-by: Babu Moger <babu.moger@amd.com> Link: https://lore.kernel.org/r/20250311183715.16445-16-james.morse@arm.com
2025-03-12x86/resctrl: Add an arch helper to reset one resourceJames Morse
On umount(), resctrl resets each resource back to its default configuration. It only ever does this for all resources in one go. reset_all_ctrls() is architecture specific as it works with struct rdt_hw_resource. Make reset_all_ctrls() an arch helper that resets one resource. Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Tony Luck <tony.luck@intel.com> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Reviewed-by: Fenghua Yu <fenghuay@nvidia.com> Reviewed-by: Babu Moger <babu.moger@amd.com> Reviewed-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com> Tested-by: Peter Newman <peternewman@google.com> Tested-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com> Tested-by: Amit Singh Tomar <amitsinght@marvell.com> # arm64 Tested-by: Shanker Donthineni <sdonthineni@nvidia.com> # arm64 Tested-by: Babu Moger <babu.moger@amd.com> Link: https://lore.kernel.org/r/20250311183715.16445-15-james.morse@arm.com
2025-03-12x86/resctrl: Move resctrl types to a separate headerJames Morse
When resctrl is fully factored into core and per-arch code, each arch will need to use some resctrl common definitions in order to define its own specializations and helpers. Following conventional practice, it would be desirable to put the dependent arch definitions in an <asm/resctrl.h> header that is included by the common <linux/resctrl.h> header. However, this can make it awkward to avoid a circular dependency between <linux/resctrl.h> and the arch header. To avoid such dependencies, move the affected common types and constants into a new header that does not need to depend on <linux/resctrl.h> or on the arch headers. The same logic applies to the monitor-configuration defines, move these too. Some kind of enumeration for events is needed between the filesystem and architecture code. Take the x86 definition as its convenient for x86. The definition of enum resctrl_event_id is needed to allow the architecture code to define resctrl_arch_mon_ctx_alloc() and resctrl_arch_mon_ctx_free(). The definition of enum resctrl_res_level is needed to allow the architecture code to define resctrl_arch_set_cdp_enabled() and resctrl_arch_get_cdp_enabled(). The bits for mbm_local_bytes_config et al are ABI, and must be the same on all architectures. These are documented in Documentation/arch/x86/resctrl.rst The maintainers entry for these headers was missed when resctrl.h was created. Add a wildcard entry to match both resctrl.h and resctrl_types.h. Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com> Reviewed-by: Tony Luck <tony.luck@intel.com> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Reviewed-by: Fenghua Yu <fenghuay@nvidia.com> Reviewed-by: Babu Moger <babu.moger@amd.com> Tested-by: Carl Worth <carl@os.amperecomputing.com> # arm64 Tested-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com> Tested-by: Peter Newman <peternewman@google.com> Tested-by: Amit Singh Tomar <amitsinght@marvell.com> # arm64 Tested-by: Shanker Donthineni <sdonthineni@nvidia.com> # arm64 Tested-by: Babu Moger <babu.moger@amd.com> Link: https://lore.kernel.org/r/20250311183715.16445-14-james.morse@arm.com
2025-03-12x86/resctrl: Move rdt_find_domain() to be visible to arch and fs codeJames Morse
rdt_find_domain() finds a domain given a resource and a cache-id. This is used by both the architecture code and the filesystem code. After the filesystem code moves to live in /fs/, this helper is either duplicated by all architectures, or needs exposing by the filesystem code. Add the declaration to the global header file. As it's now globally visible, and has only a handful of callers, swap the 'rdt' for 'resctrl'. Move the function to live with its caller in ctrlmondata.c as the filesystem code will not have anything corresponding to core.c. Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Fenghua Yu <fenghuay@nvidia.com> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Reviewed-by: Babu Moger <babu.moger@amd.com> Reviewed-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com> Tested-by: Peter Newman <peternewman@google.com> Tested-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com> Tested-by: Amit Singh Tomar <amitsinght@marvell.com> # arm64 Tested-by: Shanker Donthineni <sdonthineni@nvidia.com> # arm64 Tested-by: Babu Moger <babu.moger@amd.com> Link: https://lore.kernel.org/r/20250311183715.16445-13-james.morse@arm.com
2025-03-12x86/resctrl: Expose resctrl fs's init function to the rest of the kernelJames Morse
rdtgroup_init() needs exposing to the rest of the kernel so that arch code can call it once it lives in core code. As this is one of the few functions exposed, rename it to have "resctrl" in the name. The same goes for the exit call. Rename x86's arch code init functions for RDT to have an arch prefix to make it clear these are part of the architecture code. Co-developed-by: Dave Martin <Dave.Martin@arm.com> Signed-off-by: Dave Martin <Dave.Martin@arm.com> Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com> Reviewed-by: Tony Luck <tony.luck@intel.com> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Reviewed-by: Fenghua Yu <fenghuay@nvidia.com> Reviewed-by: Babu Moger <babu.moger@amd.com> Tested-by: Carl Worth <carl@os.amperecomputing.com> # arm64 Tested-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com> Tested-by: Peter Newman <peternewman@google.com> Tested-by: Amit Singh Tomar <amitsinght@marvell.com> # arm64 Tested-by: Shanker Donthineni <sdonthineni@nvidia.com> # arm64 Tested-by: Babu Moger <babu.moger@amd.com> Link: https://lore.kernel.org/r/20250311183715.16445-12-james.morse@arm.com
2025-03-12x86/resctrl: Remove rdtgroup from update_cpu_closid_rmid()James Morse
update_cpu_closid_rmid() takes a struct rdtgroup as an argument, which it uses to update the local CPUs default pqr values. This is a problem once the resctrl parts move out to /fs/, as the arch code cannot poke around inside struct rdtgroup. Rename update_cpu_closid_rmid() as resctrl_arch_sync_cpus_defaults() to be used as the target of an IPI, and pass the effective CLOSID and RMID in a new struct. Co-developed-by: Dave Martin <Dave.Martin@arm.com> Signed-off-by: Dave Martin <Dave.Martin@arm.com> Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com> Reviewed-by: Tony Luck <tony.luck@intel.com> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Reviewed-by: Fenghua Yu <fenghuay@nvidia.com> Reviewed-by: Babu Moger <babu.moger@amd.com> Tested-by: Carl Worth <carl@os.amperecomputing.com> # arm64 Tested-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com> Tested-by: Peter Newman <peternewman@google.com> Tested-by: Amit Singh Tomar <amitsinght@marvell.com> # arm64 Tested-by: Shanker Donthineni <sdonthineni@nvidia.com> # arm64 Tested-by: Babu Moger <babu.moger@amd.com> Link: https://lore.kernel.org/r/20250311183715.16445-11-james.morse@arm.com
2025-03-12x86/resctrl: Add helper for setting CPU default propertiesJames Morse
rdtgroup_rmdir_ctrl() and rdtgroup_rmdir_mon() set the per-CPU pqr_state for CPUs that were part of the rmdir()'d group. Another architecture might not have a 'pqr_state', its hardware may need the values in a different format. MPAM's equivalent of RMID values are not unique, and always need the CLOSID to be provided too. There is only one caller that modifies a single value, (rdtgroup_rmdir_mon()). MPAM always needs both CLOSID and RMID for the hardware value as these are written to the same system register. As rdtgroup_rmdir_mon() has the CLOSID on hand, only provide a helper to set both values. These values are read by __resctrl_sched_in(), but may be written by a different CPU without any locking, add READ/WRTE_ONCE() to avoid torn values. Co-developed-by: Dave Martin <Dave.Martin@arm.com> Signed-off-by: Dave Martin <Dave.Martin@arm.com> Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com> Reviewed-by: Tony Luck <tony.luck@intel.com> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Reviewed-by: Fenghua Yu <fenghuay@nvidia.com> Reviewed-by: Babu Moger <babu.moger@amd.com> Tested-by: Carl Worth <carl@os.amperecomputing.com> # arm64 Tested-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com> Tested-by: Peter Newman <peternewman@google.com> Tested-by: Amit Singh Tomar <amitsinght@marvell.com> # arm64 Tested-by: Shanker Donthineni <sdonthineni@nvidia.com> # arm64 Tested-by: Babu Moger <babu.moger@amd.com> Link: https://lore.kernel.org/r/20250311183715.16445-10-james.morse@arm.com
2025-03-12x86/resctrl: Generate default_ctrl instead of sharing itJames Morse
The struct rdt_resource default_ctrl is used by both the architecture code for resetting the hardware controls, and sometimes by the filesystem code as the default value for the schema, unless the bandwidth software controller is in use. Having the default exposed by the architecture code causes unnecessary duplication for each architecture as the default value must be specified, but can be derived from other schema properties. Now that the maximum bandwidth is explicitly described, resctrl can derive the default value from the schema format and the other resource properties. Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com> Reviewed-by: Tony Luck <tony.luck@intel.com> Reviewed-by: Fenghua Yu <fenghuay@nvidia.com> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Reviewed-by: Babu Moger <babu.moger@amd.com> Tested-by: Carl Worth <carl@os.amperecomputing.com> # arm64 Tested-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com> Tested-by: Peter Newman <peternewman@google.com> Tested-by: Amit Singh Tomar <amitsinght@marvell.com> # arm64 Tested-by: Shanker Donthineni <sdonthineni@nvidia.com> # arm64 Tested-by: Babu Moger <babu.moger@amd.com> Link: https://lore.kernel.org/r/20250311183715.16445-9-james.morse@arm.com
2025-03-12x86/resctrl: Add max_bw to struct resctrl_membwJames Morse
__rdt_get_mem_config_amd() and __get_mem_config_intel() both use the default_ctrl property as a maximum value. This is because the MBA schema works differently between these platforms. Doing this complicates determining whether the default_ctrl property belongs to the arch code, or can be derived from the schema format. Deriving the maximum or default value from the schema format would avoid the architecture code having to tell resctrl such obvious things as the maximum percentage is 100, and the maximum bitmap is all ones. Maximum bandwidth is always going to vary per platform. Add max_bw as a special case. This is currently used for the maximum MBA percentage on Intel platforms, but can be removed from the architecture code if 'percentage' becomes a schema format resctrl supports directly. This value isn't needed for other schema formats. This will allow the default_ctrl to be generated from the schema properties when it is needed. Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com> Reviewed-by: Tony Luck <tony.luck@intel.com> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Reviewed-by: Fenghua Yu <fenghuay@nvidia.com> Reviewed-by: Babu Moger <babu.moger@amd.com> Tested-by: Carl Worth <carl@os.amperecomputing.com> # arm64 Tested-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com> Tested-by: Peter Newman <peternewman@google.com> Tested-by: Amit Singh Tomar <amitsinght@marvell.com> # arm64 Tested-by: Shanker Donthineni <sdonthineni@nvidia.com> # arm64 Tested-by: Babu Moger <babu.moger@amd.com> Link: https://lore.kernel.org/r/20250311183715.16445-8-james.morse@arm.com
2025-03-12x86/resctrl: Remove data_width and the tabular formatJames Morse
The resctrl architecture code provides a data_width for the controls of each resource. This is used to zero pad all control values in the schemata file so they appear in columns. The same is done with the resource names to complete the visual effect. e.g. | SMBA:0=2048 | L3:0=00ff AMD platforms discover their maximum bandwidth for the MB resource from firmware, but hard-code the data_width to 4. If the maximum bandwidth requires more digits - the tabular format is silently broken. This is also broken when the mba_MBps mount option is used as the field width isn't updated. If new schema are added resctrl will need to be able to determine the maximum width. The benefit of this pretty-printing is questionable. Instead of handling runtime discovery of the data_width for AMD platforms, remove the feature. These fields are always zero padded so should be harmless to remove if the whole field has been treated as a number. In the above example, this would now look like this: | SMBA:0=2048 | L3:0=ff Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com> Reviewed-by: Tony Luck <tony.luck@intel.com> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Reviewed-by: Fenghua Yu <fenghuay@nvidia.com> Reviewed-by: Babu Moger <babu.moger@amd.com> Tested-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com> Tested-by: Peter Newman <peternewman@google.com> Tested-by: Amit Singh Tomar <amitsinght@marvell.com> # arm64 Tested-by: Shanker Donthineni <sdonthineni@nvidia.com> # arm64 Tested-by: Babu Moger <babu.moger@amd.com> Link: https://lore.kernel.org/r/20250311183715.16445-7-james.morse@arm.com
2025-03-12x86/resctrl: Use schema type to determine the schema format stringJames Morse
Resctrl's architecture code gets to specify a format string that is used when printing schema entries. This is expected to be one of two values that the filesystem code supports. Setting this format string allows the architecture code to change the ABI resctrl presents to user-space. Instead, use the schema format enum to choose which format string to use. Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Reviewed-by: Tony Luck <tony.luck@intel.com> Reviewed-by: Fenghua Yu <fenghuay@nvidia.com> Reviewed-by: Babu Moger <babu.moger@amd.com> Tested-by: Carl Worth <carl@os.amperecomputing.com> # arm64 Tested-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com> Tested-by: Peter Newman <peternewman@google.com> Tested-by: Amit Singh Tomar <amitsinght@marvell.com> # arm64 Tested-by: Shanker Donthineni <sdonthineni@nvidia.com> # arm64 Tested-by: Babu Moger <babu.moger@amd.com> Link: https://lore.kernel.org/r/20250311183715.16445-6-james.morse@arm.com
2025-03-12x86/resctrl: Use schema type to determine how to parse schema valuesJames Morse
Resctrl's architecture code gets to specify a function pointer that is used when parsing schema entries. This is expected to be one of two helpers from the filesystem code. Setting this function pointer allows the architecture code to change the ABI resctrl presents to user-space, and forces resctrl to expose these helpers. Instead, add a schema format enum to choose which schema parser to use. This allows the helpers to be made static and the structs used for passing arguments moved out of shared headers. Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com> Reviewed-by: Tony Luck <tony.luck@intel.com> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Reviewed-by: Fenghua Yu <fenghuay@nvidia.com> Reviewed-by: Babu Moger <babu.moger@amd.com> Tested-by: Carl Worth <carl@os.amperecomputing.com> # arm64 Tested-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com> Tested-by: Peter Newman <peternewman@google.com> Tested-by: Amit Singh Tomar <amitsinght@marvell.com> # arm64 Tested-by: Shanker Donthineni <sdonthineni@nvidia.com> # arm64 Tested-by: Babu Moger <babu.moger@amd.com> Link: https://lore.kernel.org/r/20250311183715.16445-5-james.morse@arm.com
2025-03-12x86/resctrl: Remove fflags from struct rdt_resourceJames Morse
The resctrl arch code specifies whether a resource controls a cache or memory using the fflags field. This field is then used by resctrl to determine which files should be exposed in the filesystem. Allowing the architecture to pick this value means the RFTYPE_ flags have to be in a shared header, and allows an architecture to create a combination that resctrl does not support. Remove the fflags field, and pick the value based on the resource id. Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com> Reviewed-by: Tony Luck <tony.luck@intel.com> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Reviewed-by: Fenghua Yu <fenghuay@nvidia.com> Reviewed-by: Babu Moger <babu.moger@amd.com> Tested-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com> Tested-by: Peter Newman <peternewman@google.com> Tested-by: Amit Singh Tomar <amitsinght@marvell.com> # arm64 Tested-by: Shanker Donthineni <sdonthineni@nvidia.com> # arm64 Tested-by: Babu Moger <babu.moger@amd.com> Link: https://lore.kernel.org/r/20250311183715.16445-4-james.morse@arm.com
2025-03-12x86/resctrl: Add a helper to avoid reaching into the arch code resource listJames Morse
Resctrl occasionally wants to know something about a specific resource, in these cases it reaches into the arch code's rdt_resources_all[] array. Once the filesystem parts of resctrl are moved to /fs/, this means it will need visibility of the architecture specific struct rdt_hw_resource definition, and the array of all resources. All architectures would also need a r_resctrl member in this struct. Instead, abstract this via a helper to allow architectures to do different things here. Move the level enum to the resctrl header and add a helper to retrieve the struct rdt_resource by 'rid'. resctrl_arch_get_resource() should not return NULL for any value in the enum, it may instead return a dummy resource that is !alloc_enabled && !mon_enabled. Co-developed-by: Dave Martin <Dave.Martin@arm.com> Signed-off-by: Dave Martin <Dave.Martin@arm.com> Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Reviewed-by: Tony Luck <tony.luck@intel.com> Reviewed-by: Fenghua Yu <fenghuay@nvidia.com> Reviewed-by: Babu Moger <babu.moger@amd.com> Tested-by: Peter Newman <peternewman@google.com> Tested-by: Carl Worth <carl@os.amperecomputing.com> # arm64 Tested-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com> Tested-by: Amit Singh Tomar <amitsinght@marvell.com> # arm64 Tested-by: Shanker Donthineni <sdonthineni@nvidia.com> # arm64 Tested-by: Babu Moger <babu.moger@amd.com> Link: https://lore.kernel.org/r/20250311183715.16445-3-james.morse@arm.com
2025-03-12x86/resctrl: Fix allocation of cleanest CLOSID on platforms with no monitorsJames Morse
Commit 6eac36bb9eb0 ("x86/resctrl: Allocate the cleanest CLOSID by searching closid_num_dirty_rmid") added logic that causes resctrl to search for the CLOSID with the fewest dirty cache lines when creating a new control group, if requested by the arch code. This depends on the values read from the llc_occupancy counters. The logic is applicable to architectures where the CLOSID effectively forms part of the monitoring identifier and so do not allow complete freedom to choose an unused monitoring identifier for a given CLOSID. This support missed that some platforms may not have these counters. This causes a NULL pointer dereference when creating a new control group as the array was not allocated by dom_data_init(). As this feature isn't necessary on platforms that don't have cache occupancy monitors, add this to the check that occurs when a new control group is allocated. Fixes: 6eac36bb9eb0 ("x86/resctrl: Allocate the cleanest CLOSID by searching closid_num_dirty_rmid") Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com> Reviewed-by: David Hildenbrand <david@redhat.com> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Reviewed-by: Tony Luck <tony.luck@intel.com> Reviewed-by: Fenghua Yu <fenghuay@nvidia.com> Reviewed-by: Babu Moger <babu.moger@amd.com> Tested-by: Carl Worth <carl@os.amperecomputing.com> # arm64 Tested-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com> Tested-by: Peter Newman <peternewman@google.com> Tested-by: Amit Singh Tomar <amitsinght@marvell.com> # arm64 Tested-by: Shanker Donthineni <sdonthineni@nvidia.com> # arm64 Tested-by: Babu Moger <babu.moger@amd.com> Link: https://lore.kernel.org/r/20250311183715.16445-2-james.morse@arm.com
2025-03-10Merge 6.14-rc6 into driver-core-nextGreg Kroah-Hartman
We need the driver core fix in here as well. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-03-10x86/microcode/AMD: Fix out-of-bounds on systems with CPU-less NUMA nodesFlorent Revest
Currently, load_microcode_amd() iterates over all NUMA nodes, retrieves their CPU masks and unconditionally accesses per-CPU data for the first CPU of each mask. According to Documentation/admin-guide/mm/numaperf.rst: "Some memory may share the same node as a CPU, and others are provided as memory only nodes." Therefore, some node CPU masks may be empty and wouldn't have a "first CPU". On a machine with far memory (and therefore CPU-less NUMA nodes): - cpumask_of_node(nid) is 0 - cpumask_first(0) is CONFIG_NR_CPUS - cpu_data(CONFIG_NR_CPUS) accesses the cpu_info per-CPU array at an index that is 1 out of bounds This does not have any security implications since flashing microcode is a privileged operation but I believe this has reliability implications by potentially corrupting memory while flashing a microcode update. When booting with CONFIG_UBSAN_BOUNDS=y on an AMD machine that flashes a microcode update. I get the following splat: UBSAN: array-index-out-of-bounds in arch/x86/kernel/cpu/microcode/amd.c:X:Y index 512 is out of range for type 'unsigned long[512]' [...] Call Trace: dump_stack __ubsan_handle_out_of_bounds load_microcode_amd request_microcode_amd reload_store kernfs_fop_write_iter vfs_write ksys_write do_syscall_64 entry_SYSCALL_64_after_hwframe Change the loop to go over only NUMA nodes which have CPUs before determining whether the first CPU on the respective node needs microcode update. [ bp: Massage commit message, fix typo. ] Fixes: 7ff6edf4fef3 ("x86/microcode/AMD: Fix mixed steppings support") Signed-off-by: Florent Revest <revest@chromium.org> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20250310144243.861978-1-revest@chromium.org
2025-03-10x86/sgx: Warn explicitly if X86_FEATURE_SGX_LC is not enabledVladis Dronov
The kernel requires X86_FEATURE_SGX_LC to be able to create SGX enclaves, not just X86_FEATURE_SGX. There is quite a number of hardware which has X86_FEATURE_SGX but not X86_FEATURE_SGX_LC. A kernel running on such hardware does not create the /dev/sgx_enclave file and does so silently. Explicitly warn if X86_FEATURE_SGX_LC is not enabled to properly notify users that the kernel disabled the SGX driver. The X86_FEATURE_SGX_LC, a.k.a. SGX Launch Control, is a CPU feature that enables LE (Launch Enclave) hash MSRs to be writable (with additional opt-in required in the 'feature control' MSR) when running enclaves, i.e. using a custom root key rather than the Intel proprietary key for enclave signing. I've hit this issue myself and have spent some time researching where my /dev/sgx_enclave file went on SGX-enabled hardware. Related links: https://github.com/intel/linux-sgx/issues/837 https://patchwork.kernel.org/project/platform-driver-x86/patch/20180827185507.17087-3-jarkko.sakkinen@linux.intel.com/ [ mingo: Made the error message a bit more verbose, and added other cases where the kernel fails to create the /dev/sgx_enclave device node. ] Signed-off-by: Vladis Dronov <vdronov@redhat.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Acked-by: Kai Huang <kai.huang@intel.com> Cc: Jarkko Sakkinen <jarkko@kernel.org> Cc: Andy Lutomirski <luto@kernel.org> Cc: Sean Christopherson <sean.j.christopherson@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: https://lore.kernel.org/r/20250309172215.21777-2-vdronov@redhat.com
2025-03-08x86/microcode/AMD: Add some forgotten models to the SHA checkBorislav Petkov (AMD)
Add some more forgotten models to the SHA check. Fixes: 50cef76d5cb0 ("x86/microcode/AMD: Load only SHA256-checksummed patches") Reported-by: Toralf Förster <toralf.foerster@gmx.de> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Signed-off-by: Ingo Molnar <mingo@kernel.org> Tested-by: Toralf Förster <toralf.foerster@gmx.de> Link: https://lore.kernel.org/r/20250307220256.11816-1-bp@kernel.org
2025-03-08Merge branch 'locking/urgent' into locking/core, to pick up locking fixesIngo Molnar
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2025-03-07Merge tag 'x86-urgent-2025-03-07' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull misc x86 fixes from Ingo Molnar: - Fix CPUID leaf 0x2 parsing bugs - Sanitize very early boot parameters to avoid crash - Fix size overflows in the SGX code - Make CALL_NOSPEC use consistent * tag 'x86-urgent-2025-03-07' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/boot: Sanitize boot params before parsing command line x86/sgx: Fix size overflows in sgx_encl_create() x86/cpu: Properly parse CPUID leaf 0x2 TLB descriptor 0x63 x86/cpu: Validate CPUID leaf 0x2 EDX output x86/cacheinfo: Validate CPUID leaf 0x2 EDX output x86/speculation: Add a conditional CS prefix to CALL_NOSPEC x86/speculation: Simplify and make CALL_NOSPEC consistent
2025-03-07x86/split_lock: Fix the delayed detection logicMaksim Davydov
If the warning mode with disabled mitigation mode is used, then on each CPU where the split lock occurred detection will be disabled in order to make progress and delayed work will be scheduled, which then will enable detection back. Now it turns out that all CPUs use one global delayed work structure. This leads to the fact that if a split lock occurs on several CPUs at the same time (within 2 jiffies), only one CPU will schedule delayed work, but the rest will not. The return value of schedule_delayed_work_on() would have shown this, but it is not checked in the code. A diagram that can help to understand the bug reproduction: - sld_update_msr() enables/disables SLD on both CPUs on the same core - schedule_delayed_work_on() internally checks WORK_STRUCT_PENDING_BIT. If a work has the 'pending' status, then schedule_delayed_work_on() will return an error code and, most importantly, the work will not be placed in the workqueue. Let's say we have a multicore system on which split_lock_mitigate=0 and a multithreaded application is running that calls splitlock in multiple threads. Due to the fact that sld_update_msr() affects the entire core (both CPUs), we will consider 2 CPUs from different cores. Let the 2 threads of this application schedule to CPU0 (core 0) and to CPU 2 (core 1), then: | || | | CPU 0 (core 0) || CPU 2 (core 1) | |_________________________________||___________________________________| | || | | 1) SPLIT LOCK occured || | | || | | 2) split_lock_warn() || | | || | | 3) sysctl_sld_mitigate == 0 || | | (work = &sl_reenable) || | | || | | 4) schedule_delayed_work_on() || | | (reenable will be called || | | after 2 jiffies on CPU 0) || | | || | | 5) disable SLD for core 0 || | | || | | ------------------------- || | | || | | || 6) SPLIT LOCK occured | | || | | || 7) split_lock_warn() | | || | | || 8) sysctl_sld_mitigate == 0 | | || (work = &sl_reenable, | | || the same address as in 3) ) | | || | | 2 jiffies || 9) schedule_delayed_work_on() | | || fials because the work is in | | || the pending state since 4). | | || The work wasn't placed to the | | || workqueue. reenable won't be | | || called on CPU 2 | | || | | || 10) disable SLD for core 0 | | || | | || From now on SLD will | | || never be reenabled on core 1 | | || | | ------------------------- || | | || | | 11) enable SLD for core 0 by || | | __split_lock_reenable || | | || | If the application threads can be scheduled to all processor cores, then over time there will be only one core left, on which SLD will be enabled and split lock will be able to be detected; and on all other cores SLD will be disabled all the time. Most likely, this bug has not been noticed for so long because sysctl_sld_mitigate default value is 1, and in this case a semaphore is used that does not allow 2 different cores to have SLD disabled at the same time, that is, strictly only one work is placed in the workqueue. In order to fix the warning mode with disabled mitigation mode, delayed work has to be per-CPU. Implement it. Fixes: 727209376f49 ("x86/split_lock: Add sysctl to control the misery mode") Signed-off-by: Maksim Davydov <davydov-max@yandex-team.ru> Signed-off-by: Ingo Molnar <mingo@kernel.org> Tested-by: Guilherme G. Piccoli <gpiccoli@igalia.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ravi Bangoria <ravi.bangoria@amd.com> Cc: Tom Lendacky <thomas.lendacky@amd.com> Link: https://lore.kernel.org/r/20250115131704.132609-1-davydov-max@yandex-team.ru
2025-03-05x86/sgx: Fix size overflows in sgx_encl_create()Jarkko Sakkinen
The total size calculated for EPC can overflow u64 given the added up page for SECS. Further, the total size calculated for shmem can overflow even when the EPC size stays within limits of u64, given that it adds the extra space for 128 byte PCMD structures (one for each page). Address this by pre-evaluating the micro-architectural requirement of SGX: the address space size must be power of two. This is eventually checked up by ECREATE but the pre-check has the additional benefit of making sure that there is some space for additional data. Fixes: 888d24911787 ("x86/sgx: Add SGX_IOC_ENCLAVE_CREATE") Reported-by: Dan Carpenter <dan.carpenter@linaro.org> Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Acked-by: Dave Hansen <dave.hansen@intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: "H. Peter Anvin" <hpa@zytor.com> Link: https://lore.kernel.org/r/20250305050006.43896-1-jarkko@kernel.org Closes: https://lore.kernel.org/linux-sgx/c87e01a0-e7dd-4749-a348-0980d3444f04@stanley.mountain/
2025-03-04Merge tag 'x86_microcode_for_v6.14_rc6' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull AMD microcode loading fixes from Borislav Petkov: - Load only sha256-signed microcode patch blobs - Other good cleanups * tag 'x86_microcode_for_v6.14_rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/microcode/AMD: Load only SHA256-checksummed patches x86/microcode/AMD: Add get_patch_level() x86/microcode/AMD: Get rid of the _load_microcode_amd() forward declaration x86/microcode/AMD: Merge early_apply_microcode() into its single callsite x86/microcode/AMD: Remove unused save_microcode_in_initrd_amd() declarations x86/microcode/AMD: Remove ugly linebreak in __verify_patch_section() signature
2025-03-04x86/stackprotector: Move __stack_chk_guard to percpu hot sectionBrian Gerst
No functional change. Signed-off-by: Brian Gerst <brgerst@gmail.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Acked-by: Uros Bizjak <ubizjak@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: https://lore.kernel.org/r/20250303165246.2175811-11-brgerst@gmail.com
2025-03-04x86/percpu: Move current_task to percpu hot sectionBrian Gerst
No functional change. Signed-off-by: Brian Gerst <brgerst@gmail.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Acked-by: Uros Bizjak <ubizjak@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: https://lore.kernel.org/r/20250303165246.2175811-10-brgerst@gmail.com
2025-03-04x86/percpu: Move top_of_stack to percpu hot sectionBrian Gerst
No functional change. Signed-off-by: Brian Gerst <brgerst@gmail.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Acked-by: Uros Bizjak <ubizjak@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: https://lore.kernel.org/r/20250303165246.2175811-9-brgerst@gmail.com
2025-03-04x86/retbleed: Move call depth to percpu hot sectionBrian Gerst
No functional change. Signed-off-by: Brian Gerst <brgerst@gmail.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Acked-by: Uros Bizjak <ubizjak@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: https://lore.kernel.org/r/20250303165246.2175811-6-brgerst@gmail.com
2025-03-04x86/preempt: Move preempt count to percpu hot sectionBrian Gerst
No functional change. Signed-off-by: Brian Gerst <brgerst@gmail.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Acked-by: Uros Bizjak <ubizjak@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: https://lore.kernel.org/r/20250303165246.2175811-4-brgerst@gmail.com
2025-03-04x86/percpu: Move pcpu_hot to percpu hot sectionBrian Gerst
Also change the alignment of the percpu hot section: - PERCPU_SECTION(INTERNODE_CACHE_BYTES) + PERCPU_SECTION(L1_CACHE_BYTES) As vSMP will muck with INTERNODE_CACHE_BYTES that invalidates the too-large-section assert we do: ASSERT(__per_cpu_hot_end - __per_cpu_hot_start <= 64, "percpu cache hot section too large") [ mingo: Added INTERNODE_CACHE_BYTES fix & explanation. ] Signed-off-by: Brian Gerst <brgerst@gmail.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Acked-by: Uros Bizjak <ubizjak@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: https://lore.kernel.org/r/20250303165246.2175811-3-brgerst@gmail.com
2025-03-04Merge branch 'x86/cpu' into x86/asm, to pick up dependent commitsIngo Molnar
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2025-03-04x86/cacheinfo: Remove unnecessary headers and reorder the restAhmed S. Darwish
Remove the headers at cacheinfo.c that are no longer required. Alphabetically reorder what remains since more headers will be included in further commits. Signed-off-by: Ahmed S. Darwish <darwi@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org> Link: https://lore.kernel.org/r/20250304085152.51092-13-darwi@linutronix.de
2025-03-04x86/cacheinfo: Remove the P4 trace leftovers for realThomas Gleixner
Commit 851026a2bf54 ("x86/cacheinfo: Remove unused trace variable") removed the switch case for LVL_TRACE but did not get rid of the surrounding gunk. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ahmed S. Darwish <darwi@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org> Link: https://lore.kernel.org/r/20250304085152.51092-12-darwi@linutronix.de
2025-03-04x86/cpu: Remove unused TLB stringsThomas Gleixner
Commit: e0ba94f14f74 ("x86/tlb_info: get last level TLB entry number of CPU") added the TLB table for parsing CPUID(0x4), including strings describing them. The string entry in the table was never used. Convert them to comments. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ahmed S. Darwish <darwi@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org> Link: https://lore.kernel.org/r/20250304085152.51092-10-darwi@linutronix.de
2025-03-04x86/cpu: Get rid of the smp_store_cpu_info() indirectionThomas Gleixner
smp_store_cpu_info() is just a wrapper around identify_secondary_cpu() without further value. Move the extra bits from smp_store_cpu_info() into identify_secondary_cpu() and remove the wrapper. [ darwi: Make it compile and fix up the xen/smp_pv.c instance ] Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ahmed S. Darwish <darwi@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org> Link: https://lore.kernel.org/r/20250304085152.51092-9-darwi@linutronix.de
2025-03-04x86/cpu: Simplify TLB entry count storageAhmed S. Darwish
Commit: e0ba94f14f74 ("x86/tlb_info: get last level TLB entry number of CPU") introduced u16 "info" arrays for each TLB type. Since 2012 and each array stores just one type of information: the number of TLB entries for its respective TLB type. Replace such arrays with simple variables. Signed-off-by: Ahmed S. Darwish <darwi@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org> Link: https://lore.kernel.org/r/20250304085152.51092-8-darwi@linutronix.de
2025-03-04x86/cpu: Use max() for CPUID leaf 0x2 TLB descriptors parsingAhmed S. Darwish
The conditional statement "if (x < y) { x = y; }" appears 22 times at the Intel leaf 0x2 descriptors parsing logic. Replace each of such instances with a max() expression to simplify the code. Signed-off-by: Ahmed S. Darwish <darwi@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org> Link: https://lore.kernel.org/r/20250304085152.51092-7-darwi@linutronix.de
2025-03-04x86/cpu: Remove unnecessary headers and reorder the restAhmed S. Darwish
Remove the headers at intel.c that are no longer required. Alphabetically reorder what remains since more headers will be included in further commits. Suggested-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ahmed S. Darwish <darwi@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org> Link: https://lore.kernel.org/r/20250304085152.51092-6-darwi@linutronix.de
2025-03-04Merge branch 'x86/urgent' into x86/cpu, to pick up dependent commitsIngo Molnar
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2025-03-04x86/cpu: Log CPU flag cmdline hacks more verboselyBrendan Jackman
Since using these options is very dangerous, make details as visible as possible: - Instead of a single message for each of the cmdline options, print a separate pr_warn() for each individual flag. - Say explicitly whether the flag is a "feature" or a "bug". Suggested-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Brendan Jackman <jackmanb@google.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Acked-by: Borislav Petkov (AMD) <bp@alien8.de> Link: https://lore.kernel.org/r/20250303-setcpuid-taint-louder-v1-3-8d255032cb4c@google.com
2025-03-04x86/cpu: Warn louder about the {set,clear}cpuid boot parametersBrendan Jackman
Commit 814165e9fd1f6 ("x86/cpu: Add the 'setcpuid=' boot parameter") recently expanded the user's ability to break their system horribly by overriding effective CPU flags. This was reflected with updates to the documentation to try and make people aware that this is dangerous. To further reduce the risk of users mistaking this for a "real feature", and try to help them figure out why their kernel is tainted if they do use it: - Upgrade the existing printk to pr_warn, to help ensure kernel logs reflect what changes are in effect. - Print an extra warning that tries to be as dramatic as possible, while also highlighting the fact that it tainted the kernel. Suggested-by: Ingo Molnar <mingo@redhat.com> Signed-off-by: Brendan Jackman <jackmanb@google.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Acked-by: Borislav Petkov (AMD) <bp@alien8.de> Link: https://lore.kernel.org/r/20250303-setcpuid-taint-louder-v1-2-8d255032cb4c@google.com
2025-03-04x86/cpu: Remove unnecessary macro indirection related to CPU feature namesBrendan Jackman
These macros used to abstract over CONFIG_X86_FEATURE_NAMES, but that was removed in: 7583e8fbdc49 ("x86/cpu: Remove X86_FEATURE_NAMES") Now they are just an unnecessary indirection, remove them. Signed-off-by: Brendan Jackman <jackmanb@google.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Acked-by: Borislav Petkov (AMD) <bp@alien8.de> Link: https://lore.kernel.org/r/20250303-setcpuid-taint-louder-v1-1-8d255032cb4c@google.com
2025-03-04x86/cpu: Properly parse CPUID leaf 0x2 TLB descriptor 0x63Ahmed S. Darwish
CPUID leaf 0x2's one-byte TLB descriptors report the number of entries for specific TLB types, among other properties. Typically, each emitted descriptor implies the same number of entries for its respective TLB type(s). An emitted 0x63 descriptor is an exception: it implies 4 data TLB entries for 1GB pages and 32 data TLB entries for 2MB or 4MB pages. For the TLB descriptors parsing code, the entry count for 1GB pages is encoded at the intel_tlb_table[] mapping, but the 2MB/4MB entry count is totally ignored. Update leaf 0x2's parsing logic 0x2 to account for 32 data TLB entries for 2MB/4MB pages implied by the 0x63 descriptor. Fixes: e0ba94f14f74 ("x86/tlb_info: get last level TLB entry number of CPU") Signed-off-by: Ahmed S. Darwish <darwi@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: stable@kernel.org Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: https://lore.kernel.org/r/20250304085152.51092-4-darwi@linutronix.de
2025-03-04x86/cpu: Validate CPUID leaf 0x2 EDX outputAhmed S. Darwish
CPUID leaf 0x2 emits one-byte descriptors in its four output registers EAX, EBX, ECX, and EDX. For these descriptors to be valid, the most significant bit (MSB) of each register must be clear. Leaf 0x2 parsing at intel.c only validated the MSBs of EAX, EBX, and ECX, but left EDX unchecked. Validate EDX's most-significant bit as well. Fixes: e0ba94f14f74 ("x86/tlb_info: get last level TLB entry number of CPU") Signed-off-by: Ahmed S. Darwish <darwi@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: stable@kernel.org Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: https://lore.kernel.org/r/20250304085152.51092-3-darwi@linutronix.de
2025-03-04x86/cacheinfo: Validate CPUID leaf 0x2 EDX outputAhmed S. Darwish
CPUID leaf 0x2 emits one-byte descriptors in its four output registers EAX, EBX, ECX, and EDX. For these descriptors to be valid, the most significant bit (MSB) of each register must be clear. The historical Git commit: 019361a20f016 ("- pre6: Intel: start to add Pentium IV specific stuff (128-byte cacheline etc)...") introduced leaf 0x2 output parsing. It only validated the MSBs of EAX, EBX, and ECX, but left EDX unchecked. Validate EDX's most-significant bit. Signed-off-by: Ahmed S. Darwish <darwi@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: stable@vger.kernel.org Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: https://lore.kernel.org/r/20250304085152.51092-2-darwi@linutronix.de
2025-03-03x86/bugs: Make spectre user default depend on MITIGATION_SPECTRE_V2Breno Leitao
Change the default value of spectre v2 in user mode to respect the CONFIG_MITIGATION_SPECTRE_V2 config option. Currently, user mode spectre v2 is set to auto (SPECTRE_V2_USER_CMD_AUTO) by default, even if CONFIG_MITIGATION_SPECTRE_V2 is disabled. Set the spectre_v2 value to auto (SPECTRE_V2_USER_CMD_AUTO) if the Spectre v2 config (CONFIG_MITIGATION_SPECTRE_V2) is enabled, otherwise set the value to none (SPECTRE_V2_USER_CMD_NONE). Important to say the command line argument "spectre_v2_user" overwrites the default value in both cases. When CONFIG_MITIGATION_SPECTRE_V2 is not set, users have the flexibility to opt-in for specific mitigations independently. In this scenario, setting spectre_v2= will not enable spectre_v2_user=, and command line options spectre_v2_user and spectre_v2 are independent when CONFIG_MITIGATION_SPECTRE_V2=n. Signed-off-by: Breno Leitao <leitao@debian.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Reviewed-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com> Acked-by: Josh Poimboeuf <jpoimboe@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: David Kaplan <David.Kaplan@amd.com> Link: https://lore.kernel.org/r/20241031-x86_bugs_last_v2-v2-2-b7ff1dab840e@debian.org
2025-03-03x86/bugs: Use the cpu_smt_possible() helper instead of open-coded codeBreno Leitao
There is a helper function to check if SMT is available. Use this helper instead of performing the check manually. The helper function cpu_smt_possible() does exactly the same thing as was being done manually inside spectre_v2_user_select_mitigation(). Specifically, it returns false if CONFIG_SMP is disabled, otherwise it checks the cpu_smt_control global variable. This change improves code consistency and reduces duplication. No change in functionality intended. Signed-off-by: Breno Leitao <leitao@debian.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Reviewed-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com> Cc: David Kaplan <David.Kaplan@amd.com> Link: https://lore.kernel.org/r/20241031-x86_bugs_last_v2-v2-1-b7ff1dab840e@debian.org
2025-02-28x86/bugs: Add AUTO mitigations for mds/taa/mmio/rfdsDavid Kaplan
Add AUTO mitigations for mds/taa/mmio/rfds to create consistent vulnerability handling. These AUTO mitigations will be turned into the appropriate default mitigations in the <vuln>_select_mitigation() functions. Later, these will be used with the new attack vector controls to help select appropriate mitigations. Signed-off-by: David Kaplan <david.kaplan@amd.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Link: https://lore.kernel.org/r/20250108202515.385902-4-david.kaplan@amd.com
2025-02-28x86/bugs: Relocate mds/taa/mmio/rfds definesDavid Kaplan
Move the mds, taa, mmio, and rfds mitigation enums earlier in the file to prepare for restructuring of these mitigations as they are all inter-related. No functional change. Signed-off-by: David Kaplan <david.kaplan@amd.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Link: https://lore.kernel.org/r/20250108202515.385902-3-david.kaplan@amd.com