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Author SHA1 Message Date
Thomas Gleixner
2e1997335c x86/microcode: Get rid of the schedule work indirection
Scheduling work on all CPUs to collect the microcode information is just
another extra step for no value. Let the CPU hotplug callback registration
do it.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Link: https://lore.kernel.org/r/20231017211723.354748138@linutronix.de
2023-10-24 15:05:54 +02:00
Thomas Gleixner
8529e8ab6c x86/microcode: Mop up early loading leftovers
Get rid of the initrd_gone hack which was required to keep
find_microcode_in_initrd() functional after init.

As find_microcode_in_initrd() is now only used during init, mark it
accordingly.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Link: https://lore.kernel.org/r/20231017211723.298854846@linutronix.de
2023-10-24 15:05:54 +02:00
Thomas Gleixner
5af05b8d51 x86/microcode/amd: Use cached microcode for AP load
Now that the microcode cache is initialized before the APs are brought
up, there is no point in scanning builtin/initrd microcode during AP
loading.

Convert the AP loader to utilize the cache, which in turn makes the CPU
hotplug callback which applies the microcode after initrd/builtin is
gone, obsolete as the early loading during late hotplug operations
including the resume path depends now only on the cache.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Link: https://lore.kernel.org/r/20231017211723.243426023@linutronix.de
2023-10-24 15:05:54 +02:00
Thomas Gleixner
a7939f0167 x86/microcode/amd: Cache builtin/initrd microcode early
There is no reason to scan builtin/initrd microcode on each AP.

Cache the builtin/initrd microcode in an early initcall so that the
early AP loader can utilize the cache.

The existing fs initcall which invoked save_microcode_in_initrd_amd() is
still required to maintain the initrd_gone flag. Rename it accordingly.
This will be removed once the AP loader code is converted to use the
cache.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Link: https://lore.kernel.org/r/20231017211723.187566507@linutronix.de
2023-10-24 15:05:54 +02:00
Thomas Gleixner
d419d28261 x86/microcode/amd: Cache builtin microcode too
save_microcode_in_initrd_amd() fails to cache builtin microcode and only
scans initrd.

Use find_blobs_in_containers() instead which covers both.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Link: https://lore.kernel.org/r/20231010150702.495139089@linutronix.de
2023-10-24 15:05:54 +02:00
Thomas Gleixner
ecfd410893 x86/microcode/amd: Use correct per CPU ucode_cpu_info
find_blobs_in_containers() is invoked on every CPU but overwrites
unconditionally ucode_cpu_info of CPU0.

Fix this by using the proper CPU data and move the assignment into the
call site apply_ucode_from_containers() so that the function can be
reused.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Link: https://lore.kernel.org/r/20231010150702.433454320@linutronix.de
2023-10-24 15:05:54 +02:00
Thomas Gleixner
b48b26f992 x86/microcode: Remove pointless apply() invocation
Microcode is applied on the APs during early bringup. There is no point
in trying to apply the microcode again during the hotplug operations and
neither at the point where the microcode device is initialized.

Collect CPU info and microcode revision in setup_online_cpu() for now.
This will move to the CPU hotplug callback later.

  [ bp: Leave the starting notifier for the following scenario:

    - boot, late load, suspend to disk, resume

    without the starting notifier, only the last core manages to update the
    microcode upon resume:

    # rdmsr -a 0x8b
    10000bf
    10000bf
    10000bf
    10000bf
    10000bf
    10000dc <----

    This is on an AMD F10h machine.

    For the future, one should check whether potential unification of
    the CPU init path could cover the resume path too so that this can
    be simplified even more.

  tglx: This is caused by the odd handling of APs which try to find the
  microcode blob in builtin or initrd instead of caching the microcode
  blob during early init before the APs are brought up. Will be cleaned
  up in a later step. ]

Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20231017211723.018821624@linutronix.de
2023-10-24 15:05:54 +02:00
Thomas Gleixner
b7fcd995b2 x86/microcode/intel: Rework intel_find_matching_signature()
Take a cpu_signature argument and work from there. Move the match()
helper next to the callsite as there is no point for having it in
a header.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Link: https://lore.kernel.org/r/20231002115902.797820205@linutronix.de
2023-10-24 15:05:54 +02:00
Thomas Gleixner
11f96ac4c2 x86/microcode/intel: Reuse intel_cpu_collect_info()
No point for an almost duplicate function.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Link: https://lore.kernel.org/r/20231002115902.741173606@linutronix.de
2023-10-24 15:05:54 +02:00
Thomas Gleixner
164aa1ca53 x86/microcode/intel: Rework intel_cpu_collect_info()
Nothing needs struct ucode_cpu_info. Make it take struct cpu_signature,
let it return a boolean and simplify the implementation. Rename it now
that the silly name clash with collect_cpu_info() is gone.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Link: https://lore.kernel.org/r/20231017211722.851573238@linutronix.de
2023-10-24 15:05:53 +02:00
Thomas Gleixner
3973718cff x86/microcode/intel: Unify microcode apply() functions
Deduplicate the early and late apply() functions.

  [ bp: Rename the function which does the actual application to
      __apply_microcode() to differentiate it from
      microcode_ops.apply_microcode(). ]

Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20231017211722.795508212@linutronix.de
2023-10-24 15:05:53 +02:00
Thomas Gleixner
f24f204405 x86/microcode/intel: Switch to kvmalloc()
Microcode blobs are getting larger and might soon reach the kmalloc()
limit. Switch over kvmalloc().

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Link: https://lore.kernel.org/r/20231002115902.564323243@linutronix.de
2023-10-24 15:05:53 +02:00
Thomas Gleixner
2a1dada3d1 x86/microcode/intel: Save the microcode only after a successful late-load
There are situations where the late microcode is loaded into memory but
is not applied:

  1) The rendezvous fails
  2) The microcode is rejected by the CPUs

If any of this happens then the pointer which was updated at firmware
load time is stale and subsequent CPU hotplug operations either fail to
update or create inconsistent microcode state.

Save the loaded microcode in a separate pointer before the late load is
attempted and when successful, update the hotplug pointer accordingly
via a new microcode_ops callback.

Remove the pointless fallback in the loader to a microcode pointer which
is never populated.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Link: https://lore.kernel.org/r/20231002115902.505491309@linutronix.de
2023-10-24 15:05:53 +02:00
Thomas Gleixner
dd5e3e3ca6 x86/microcode/intel: Simplify early loading
The early loading code is overly complicated:

  - It scans the builtin/initrd for microcode not only on the BSP, but also
    on all APs during early boot and then later in the boot process it
    scans again to duplicate and save the microcode before initrd goes
    away.

    That's a pointless exercise because this can be simply done before
    bringing up the APs when the memory allocator is up and running.

 - Saving the microcode from within the scan loop is completely
   non-obvious and a left over of the microcode cache.

   This can be done at the call site now which makes it obvious.

Rework the code so that only the BSP scans the builtin/initrd microcode
once during early boot and save it away in an early initcall for later
use.

  [ bp: Test and fold in a fix from tglx ontop which handles the need to
    distinguish what save_microcode() does depending on when it is
    called:

     - when on the BSP during early load, it needs to find a newer
       revision than the one currently loaded on the BSP

     - later, before SMP init, it still runs on the BSP and gets the BSP
       revision just loaded and uses that revision to know which patch
       to save for the APs. For that it needs to find the exact one as
       on the BSP.
   ]

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Link: https://lore.kernel.org/r/20231017211722.629085215@linutronix.de
2023-10-24 15:02:36 +02:00
Ingo Molnar
4e5b65a22b Linux 6.6-rc7
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Merge tag 'v6.6-rc7' into sched/core, to pick up fixes

Pick up recent sched/urgent fixes merged upstream.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2023-10-23 11:32:25 +02:00
Alexey Dobriyan
321a145137 x86/callthunks: Delete unused "struct thunk_desc"
It looks like it was never used.

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: linux-kernel@vger.kernel.org
Link: https://lore.kernel.org/r/843bf596-db67-4b33-a865-2bae4a4418e5@p183
2023-10-20 12:58:48 +02:00
Yang Li
904e1ddd0b x86/srso: Remove unnecessary semicolon
scripts/coccinelle/misc/semicolon.cocci reports:

  arch/x86/kernel/cpu/bugs.c:713:2-3: Unneeded semicolon

Signed-off-by: Yang Li <yang.lee@linux.alibaba.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Link: https://lore.kernel.org/r/20230810010550.25733-1-yang.lee@linux.alibaba.com
2023-10-20 12:50:35 +02:00
Josh Poimboeuf
99ee56c765 x86/calldepth: Rename __x86_return_skl() to call_depth_return_thunk()
For consistency with the other return thunks, rename __x86_return_skl()
to call_depth_return_thunk().

Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Acked-by: Borislav Petkov (AMD) <bp@alien8.de>
Link: https://lore.kernel.org/r/ae44e9f9976934e3b5b47a458d523ccb15867561.1693889988.git.jpoimboe@kernel.org
2023-10-20 12:45:48 +02:00
Josh Poimboeuf
34a3cae747 x86/srso: Disentangle rethunk-dependent options
CONFIG_RETHUNK, CONFIG_CPU_UNRET_ENTRY and CONFIG_CPU_SRSO are all
tangled up.  De-spaghettify the code a bit.

Some of the rethunk-related code has been shuffled around within the
'.text..__x86.return_thunk' section, but otherwise there are no
functional changes.  srso_alias_untrain_ret() and srso_alias_safe_ret()
((which are very address-sensitive) haven't moved.

Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Acked-by: Borislav Petkov (AMD) <bp@alien8.de>
Link: https://lore.kernel.org/r/2845084ed303d8384905db3b87b77693945302b4.1693889988.git.jpoimboe@kernel.org
2023-10-20 12:30:50 +02:00
Josh Poimboeuf
351236947a x86/srso: Move retbleed IBPB check into existing 'has_microcode' code block
Simplify the code flow a bit by moving the retbleed IBPB check into the
existing 'has_microcode' block.

Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Acked-by: Borislav Petkov (AMD) <bp@alien8.de>
Link: https://lore.kernel.org/r/0a22b86b1f6b07f9046a9ab763fc0e0d1b7a91d4.1693889988.git.jpoimboe@kernel.org
2023-10-20 12:29:25 +02:00
Josh Poimboeuf
0a0ce0da7f x86/bugs: Remove default case for fully switched enums
For enum switch statements which handle all possible cases, remove the
default case so a compiler warning gets printed if one of the enums gets
accidentally omitted from the switch statement.

Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Acked-by: Borislav Petkov (AMD) <bp@alien8.de>
Link: https://lore.kernel.org/r/fcf6feefab991b72e411c2aed688b18e65e06aed.1693889988.git.jpoimboe@kernel.org
2023-10-20 12:28:44 +02:00
Josh Poimboeuf
55ca9010c4 x86/srso: Remove 'pred_cmd' label
SBPB is only enabled in two distinct cases:

1) when SRSO has been disabled with srso=off

2) when SRSO has been fixed (in future HW)

Simplify the control flow by getting rid of the 'pred_cmd' label and
moving the SBPB enablement check to the two corresponding code sites.
This makes it more clear when exactly SBPB gets enabled.

Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Acked-by: Borislav Petkov (AMD) <bp@alien8.de>
Link: https://lore.kernel.org/r/bb20e8569cfa144def5e6f25e610804bc4974de2.1693889988.git.jpoimboe@kernel.org
2023-10-20 12:26:59 +02:00
Josh Poimboeuf
dc6306ad5b x86/srso: Fix vulnerability reporting for missing microcode
The SRSO default safe-ret mitigation is reported as "mitigated" even if
microcode hasn't been updated.  That's wrong because userspace may still
be vulnerable to SRSO attacks due to IBPB not flushing branch type
predictions.

Report the safe-ret + !microcode case as vulnerable.

Also report the microcode-only case as vulnerable as it leaves the
kernel open to attacks.

Fixes: fb3bd914b3 ("x86/srso: Add a Speculative RAS Overflow mitigation")
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Acked-by: Borislav Petkov (AMD) <bp@alien8.de>
Link: https://lore.kernel.org/r/a8a14f97d1b0e03ec255c81637afdf4cf0ae9c99.1693889988.git.jpoimboe@kernel.org
2023-10-20 11:46:09 +02:00
Josh Poimboeuf
de9f5f7b06 x86/srso: Print mitigation for retbleed IBPB case
When overriding the requested mitigation with IBPB due to retbleed=ibpb,
print the mitigation in the usual format instead of a custom error
message.

Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Acked-by: Borislav Petkov (AMD) <bp@alien8.de>
Link: https://lore.kernel.org/r/ec3af919e267773d896c240faf30bfc6a1fd6304.1693889988.git.jpoimboe@kernel.org
2023-10-20 11:45:24 +02:00
Josh Poimboeuf
3fc7b28e83 x86/srso: Print actual mitigation if requested mitigation isn't possible
If the kernel wasn't compiled to support the requested option, print the
actual option that ends up getting used.

Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Borislav Petkov (AMD) <bp@alien8.de>
Acked-by: Borislav Petkov (AMD) <bp@alien8.de>
Link: https://lore.kernel.org/r/7e7a12ea9d85a9f76ca16a3efb71f262dee46ab1.1693889988.git.jpoimboe@kernel.org
2023-10-20 11:44:26 +02:00
Josh Poimboeuf
1d1142ac51 x86/srso: Fix SBPB enablement for (possible) future fixed HW
Make the SBPB check more robust against the (possible) case where future
HW has SRSO fixed but doesn't have the SRSO_NO bit set.

Fixes: 1b5277c0ea ("x86/srso: Add SRSO_NO support")
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Acked-by: Borislav Petkov (AMD) <bp@alien8.de>
Link: https://lore.kernel.org/r/cee5050db750b391c9f35f5334f8ff40e66c01b9.1693889988.git.jpoimboe@kernel.org
2023-10-20 11:34:51 +02:00
Linus Torvalds
0df072ab65 Take care of a race between when the #VC exception is raised and when
the guest kernel gets to emulate certain instructions in SEV-{ES,SNP}
 guests by:
 
 - disabling emulation of MMIO instructions when coming from user mode
 
 - checking the IO permission bitmap before emulating IO instructions and
   verifying the memory operands of INS/OUTS insns.
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Merge tag 'sev_fixes_for_v6.6' of //git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 fixes from Borislav Petkov:
 "Take care of a race between when the #VC exception is raised and when
  the guest kernel gets to emulate certain instructions in SEV-{ES,SNP}
  guests by:

   - disabling emulation of MMIO instructions when coming from user mode

   - checking the IO permission bitmap before emulating IO instructions
     and verifying the memory operands of INS/OUTS insns"

* tag 'sev_fixes_for_v6.6' of //git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/sev: Check for user-space IOIO pointing to kernel space
  x86/sev: Check IOBM for IOIO exceptions from user-space
  x86/sev: Disable MMIO emulation from user mode
2023-10-19 18:12:08 -07:00
Thomas Gleixner
0177669ee6 x86/microcode/intel: Cleanup code further
Sanitize the microcode scan loop, fixup printks and move the loading
function for builtin microcode next to the place where it is used and mark
it __init.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Link: https://lore.kernel.org/r/20231002115902.389400871@linutronix.de
2023-10-19 14:10:50 +02:00
Thomas Gleixner
6b072022ab x86/microcode/intel: Simplify and rename generic_load_microcode()
so it becomes less obfuscated and rename it because there is nothing
generic about it.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Link: https://lore.kernel.org/r/20231002115902.330295409@linutronix.de
2023-10-19 14:10:00 +02:00
Thomas Gleixner
b0f0bf5eef x86/microcode/intel: Simplify scan_microcode()
Make it readable and comprehensible.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Link: https://lore.kernel.org/r/20231002115902.271940980@linutronix.de
2023-10-19 12:32:40 +02:00
Ashok Raj
ae76d951f6 x86/microcode/intel: Rip out mixed stepping support for Intel CPUs
Mixed steppings aren't supported on Intel CPUs. Only one microcode patch
is required for the entire system. The caching of microcode blobs which
match the family and model is therefore pointless and in fact is
dysfunctional as CPU hotplug updates use only a single microcode blob,
i.e. the one where *intel_ucode_patch points to.

Remove the microcode cache and make it an AMD local feature.

  [ tglx:
     - save only at the end. Otherwise random microcode ends up in the
  	  pointer for early loading
     - free the ucode patch pointer in save_microcode_patch() only
    after kmemdup() has succeeded, as reported by Andrew Cooper ]

Originally-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ashok Raj <ashok.raj@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Link: https://lore.kernel.org/r/20231017211722.404362809@linutronix.de
2023-10-19 12:29:39 +02:00
Thomas Gleixner
0b62f6cb07 x86/microcode/32: Move early loading after paging enable
32-bit loads microcode before paging is enabled. The commit which
introduced that has zero justification in the changelog. The cover
letter has slightly more content, but it does not give any technical
justification either:

  "The problem in current microcode loading method is that we load a
   microcode way, way too late; ideally we should load it before turning
   paging on.  This may only be practical on 32 bits since we can't get
   to 64-bit mode without paging on, but we should still do it as early
   as at all possible."

Handwaving word salad with zero technical content.

Someone claimed in an offlist conversation that this is required for
curing the ATOM erratum AAE44/AAF40/AAG38/AAH41. That erratum requires
an microcode update in order to make the usage of PSE safe. But during
early boot, PSE is completely irrelevant and it is evaluated way later.

Neither is it relevant for the AP on single core HT enabled CPUs as the
microcode loading on the AP is not doing anything.

On dual core CPUs there is a theoretical problem if a split of an
executable large page between enabling paging including PSE and loading
the microcode happens. But that's only theoretical, it's practically
irrelevant because the affected dual core CPUs are 64bit enabled and
therefore have paging and PSE enabled before loading the microcode on
the second core. So why would it work on 64-bit but not on 32-bit?

The erratum:

  "AAG38 Code Fetch May Occur to Incorrect Address After a Large Page is
   Split Into 4-Kbyte Pages

   Problem: If software clears the PS (page size) bit in a present PDE
   (page directory entry), that will cause linear addresses mapped through
   this PDE to use 4-KByte pages instead of using a large page after old
   TLB entries are invalidated. Due to this erratum, if a code fetch uses
   this PDE before the TLB entry for the large page is invalidated then it
   may fetch from a different physical address than specified by either the
   old large page translation or the new 4-KByte page translation. This
   erratum may also cause speculative code fetches from incorrect addresses."

The practical relevance for this is exactly zero because there is no
splitting of large text pages during early boot-time, i.e. between paging
enable and microcode loading, and neither during CPU hotplug.

IOW, this load microcode before paging enable is yet another voodoo
programming solution in search of a problem. What's worse is that it causes
at least two serious problems:

 1) When stackprotector is enabled, the microcode loader code has the
    stackprotector mechanics enabled. The read from the per CPU variable
    __stack_chk_guard is always accessing the virtual address either
    directly on UP or via %fs on SMP. In physical address mode this
    results in an access to memory above 3GB. So this works by chance as
    the hardware returns the same value when there is no RAM at this
    physical address. When there is RAM populated above 3G then the read
    is by chance the same as nothing changes that memory during the very
    early boot stage. That's not necessarily true during runtime CPU
    hotplug.

 2) When function tracing is enabled, the relevant microcode loader
    functions and the functions invoked from there will call into the
    tracing code and evaluate global and per CPU variables in physical
    address mode. What could potentially go wrong?

Cure this and move the microcode loading after the early paging enable, use
the new temporary initrd mapping and remove the gunk in the microcode
loader which is required to handle physical address mode.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Link: https://lore.kernel.org/r/20231017211722.348298216@linutronix.de
2023-10-18 22:15:01 +02:00
Thomas Gleixner
4c585af718 x86/boot/32: Temporarily map initrd for microcode loading
Early microcode loading on 32-bit runs in physical address mode because
the initrd is not covered by the initial page tables. That results in
a horrible mess all over the microcode loader code.

Provide a temporary mapping for the initrd in the initial page tables by
appending it to the actual initial mapping starting with a new PGD or
PMD depending on the configured page table levels ([non-]PAE).

The page table entries are located after _brk_end so they are not
permanently using memory space. The mapping is invalidated right away in
i386_start_kernel() after the early microcode loader has run.

This prepares for removing the physical address mode oddities from all
over the microcode loader code, which in turn allows further cleanups.

Provide the map and unmap code and document the place where the
microcode loader needs to be invoked with a comment.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Link: https://lore.kernel.org/r/20231017211722.292291436@linutronix.de
2023-10-18 18:28:41 +02:00
Thomas Gleixner
69ba866db2 x86/boot/32: Restructure mk_early_pgtbl_32()
Prepare it for adding a temporary initrd mapping by splitting out the
actual map loop.

No functional change.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Link: https://lore.kernel.org/r/20231017211722.175910753@linutronix.de
2023-10-18 18:28:41 +02:00
Thomas Gleixner
a62f4ca106 x86/boot/32: De-uglify the 2/3 level paging difference in mk_early_pgtbl_32()
Move the ifdeffery out of the function and use proper typedefs to make it
work for both 2 and 3 level paging.

No functional change.

  [ bp: Move mk_early_pgtbl_32() declaration into a header. ]

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Link: https://lore.kernel.org/r/20231017211722.111059491@linutronix.de
2023-10-18 18:27:30 +02:00
Thomas Gleixner
1e2dd572d2 x86/boot: Use __pa_nodebug() in mk_early_pgtbl_32()
Use the existing macro instead of undefining and redefining __pa().

No functional change.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Link: https://lore.kernel.org/r/20231017211722.051625827@linutronix.de
2023-10-18 11:24:37 +02:00
Thomas Gleixner
242db75894 x86/boot/32: Disable stackprotector and tracing for mk_early_pgtbl_32()
Stackprotector cannot work before paging is enabled. The read from the per
CPU variable __stack_chk_guard is always accessing the virtual address
either directly on UP or via FS on SMP. In physical address mode this
results in an access to memory above 3GB.

So this works by chance as the hardware returns the same value when there
is no RAM at this physical address. When there is RAM populated above 3G
then the read is by chance the same as nothing changes that memory during
the very early boot stage.

Stop relying on pure luck and disable the stack protector for the only C
function which is called during early boot before paging is enabled.

Remove function tracing from the whole source file as there is no way to
trace this at all, but in case of CONFIG_DYNAMIC_FTRACE=n
mk_early_pgtbl_32() would access global function tracer variables in
physical address mode which again might work by chance.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Link: https://lore.kernel.org/r/20231002115902.156063939@linutronix.de
2023-10-18 11:11:43 +02:00
Paolo Bonzini
2e9064facc x86/microcode/amd: Fix snprintf() format string warning in W=1 build
Building with GCC 11.x results in the following warning:

  arch/x86/kernel/cpu/microcode/amd.c: In function ‘find_blobs_in_containers’:
  arch/x86/kernel/cpu/microcode/amd.c:504:58: error: ‘h.bin’ directive output may be truncated writing 5 bytes into a region of size between 1 and 7 [-Werror=format-truncation=]
  arch/x86/kernel/cpu/microcode/amd.c:503:17: note: ‘snprintf’ output between 35 and 41 bytes into a destination of size 36

The issue is that GCC does not know that the family can only be a byte
(it ultimately comes from CPUID).  Suggest the right size to the compiler
by marking the argument as char-size ("hh").  While at it, instead of
using the slightly more obscure precision specifier use the width with
zero padding (over 23000 occurrences in kernel sources, vs 500 for
the idiom using the precision).

Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Closes: https://lore.kernel.org/oe-kbuild-all/202308252255.2HPJ6x5Q-lkp@intel.com/
Link: https://lore.kernel.org/r/20231016224858.2829248-1-pbonzini@redhat.com
2023-10-17 23:51:58 +02:00
Hou Wenlong
d2a285d65b x86/head/64: Move the __head definition to <asm/init.h>
Move the __head section definition to a header to widen its use.

An upcoming patch will mark the code as __head in mem_encrypt_identity.c too.

Signed-off-by: Hou Wenlong <houwenlong.hwl@antgroup.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/0583f57977be184689c373fe540cbd7d85ca2047.1697525407.git.houwenlong.hwl@antgroup.com
2023-10-17 14:51:14 +02:00
Babu Moger
4cee14bcb1 x86/resctrl: Display RMID of resource group
In x86, hardware uses RMID to identify a monitoring group. When a user
creates a monitor group these details are not visible. These details
can help resctrl debugging.

Add RMID(mon_hw_id) to the monitor groups display in the resctrl interface.
Users can see these details when resctrl is mounted with "-o debug" option.

Add RFTYPE_MON_BASE that complements existing RFTYPE_CTRL_BASE and
represents files belonging to monitoring groups.

Other architectures do not use "RMID". Use the name mon_hw_id to refer
to "RMID" in an effort to keep the naming generic.

For example:
  $cat /sys/fs/resctrl/mon_groups/mon_grp1/mon_hw_id
  3

Signed-off-by: Babu Moger <babu.moger@amd.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Peter Newman <peternewman@google.com>
Reviewed-by: Tan Shaopeng <tan.shaopeng@jp.fujitsu.com>
Reviewed-by: Fenghua Yu <fenghua.yu@intel.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Tested-by: Peter Newman <peternewman@google.com>
Tested-by: Tan Shaopeng <tan.shaopeng@jp.fujitsu.com>
Link: https://lore.kernel.org/r/20231017002308.134480-10-babu.moger@amd.com
2023-10-17 14:05:40 +02:00
Babu Moger
918f211b5e x86/resctrl: Add support for the files of MON groups only
Files unique to monitoring groups have the RFTYPE_MON flag. When a new
monitoring group is created the resctrl files with flags RFTYPE_BASE
(files common to all resource groups) and RFTYPE_MON (files unique to
monitoring groups) are created to support interacting with the new
monitoring group.

A resource group can support both monitoring and control, also termed
a CTRL_MON resource group. CTRL_MON groups should get both monitoring
and control resctrl files but that is not the case. Only the
RFTYPE_BASE and RFTYPE_CTRL files are created for CTRL_MON groups.

Ensure that files with the RFTYPE_MON flag are created for CTRL_MON groups.

Signed-off-by: Babu Moger <babu.moger@amd.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Peter Newman <peternewman@google.com>
Reviewed-by: Tan Shaopeng <tan.shaopeng@jp.fujitsu.com>
Reviewed-by: Fenghua Yu <fenghua.yu@intel.com>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Tested-by: Peter Newman <peternewman@google.com>
Tested-by: Tan Shaopeng <tan.shaopeng@jp.fujitsu.com>
Link: https://lore.kernel.org/r/20231017002308.134480-9-babu.moger@amd.com
2023-10-17 14:05:24 +02:00
Babu Moger
ca8dad225e x86/resctrl: Display CLOSID for resource group
In x86, hardware uses CLOSID to identify a control group. When a user
creates a control group this information is not visible to the user. It
can help resctrl debugging.

Add CLOSID(ctrl_hw_id) to the control groups display in the resctrl
interface. Users can see this detail when resctrl is mounted with the
"-o debug" option.

Other architectures do not use "CLOSID". Use the names ctrl_hw_id to refer
to "CLOSID" in an effort to keep the naming generic.

For example:
  $cat /sys/fs/resctrl/ctrl_grp1/ctrl_hw_id
  1

Signed-off-by: Babu Moger <babu.moger@amd.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Peter Newman <peternewman@google.com>
Reviewed-by: Tan Shaopeng <tan.shaopeng@jp.fujitsu.com>
Reviewed-by: Fenghua Yu <fenghua.yu@intel.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Tested-by: Peter Newman <peternewman@google.com>
Tested-by: Tan Shaopeng <tan.shaopeng@jp.fujitsu.com>
Link: https://lore.kernel.org/r/20231017002308.134480-8-babu.moger@amd.com
2023-10-17 14:05:14 +02:00
Babu Moger
cb07d71f01 x86/resctrl: Introduce "-o debug" mount option
Add "-o debug" option to mount resctrl filesystem in debug mode.  When
in debug mode resctrl displays files that have the new RFTYPE_DEBUG flag
to help resctrl debugging.

Signed-off-by: Babu Moger <babu.moger@amd.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Peter Newman <peternewman@google.com>
Reviewed-by: Tan Shaopeng <tan.shaopeng@jp.fujitsu.com>
Reviewed-by: Fenghua Yu <fenghua.yu@intel.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Tested-by: Peter Newman <peternewman@google.com>
Tested-by: Tan Shaopeng <tan.shaopeng@jp.fujitsu.com>
Link: https://lore.kernel.org/r/20231017002308.134480-7-babu.moger@amd.com
2023-10-17 13:07:17 +02:00
Babu Moger
d27567a0eb x86/resctrl: Move default group file creation to mount
The default resource group and its files are created during kernel init
time. Upcoming changes will make some resctrl files optional based on
a mount parameter. If optional files are to be added to the default
group based on the mount option, then each new file needs to be created
separately and call kernfs_activate() again.

Create all files of the default resource group during resctrl mount,
destroyed during unmount, to avoid scattering resctrl file addition
across two separate code flows.

Signed-off-by: Babu Moger <babu.moger@amd.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Peter Newman <peternewman@google.com>
Reviewed-by: Tan Shaopeng <tan.shaopeng@jp.fujitsu.com>
Reviewed-by: Fenghua Yu <fenghua.yu@intel.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Tested-by: Peter Newman <peternewman@google.com>
Tested-by: Tan Shaopeng <tan.shaopeng@jp.fujitsu.com>
Link: https://lore.kernel.org/r/20231017002308.134480-6-babu.moger@amd.com
2023-10-17 12:50:53 +02:00
Babu Moger
df5f3a1dd8 x86/resctrl: Unwind properly from rdt_enable_ctx()
rdt_enable_ctx() enables the features provided during resctrl mount.

Additions to rdt_enable_ctx() are required to also modify error paths
of rdt_enable_ctx() callers to ensure correct unwinding if errors
are encountered after calling rdt_enable_ctx(). This is error prone.

Introduce rdt_disable_ctx() to refactor the error unwinding of
rdt_enable_ctx() to simplify future additions. This also simplifies
cleanup in rdt_kill_sb().

Suggested-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: Babu Moger <babu.moger@amd.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Peter Newman <peternewman@google.com>
Reviewed-by: Tan Shaopeng <tan.shaopeng@jp.fujitsu.com>
Reviewed-by: Fenghua Yu <fenghua.yu@intel.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Tested-by: Peter Newman <peternewman@google.com>
Tested-by: Tan Shaopeng <tan.shaopeng@jp.fujitsu.com>
Link: https://lore.kernel.org/r/20231017002308.134480-5-babu.moger@amd.com
2023-10-17 12:49:02 +02:00
Babu Moger
d41592435c x86/resctrl: Rename rftype flags for consistency
resctrl associates rftype flags with its files so that files can be chosen
based on the resource, whether it is info or base, and if it is control
or monitor type file. These flags use the RF_ as well as RFTYPE_ prefixes.

Change the prefix to RFTYPE_ for all these flags to be consistent.

Signed-off-by: Babu Moger <babu.moger@amd.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Peter Newman <peternewman@google.com>
Reviewed-by: Tan Shaopeng <tan.shaopeng@jp.fujitsu.com>
Reviewed-by: Fenghua Yu <fenghua.yu@intel.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Tested-by: Peter Newman <peternewman@google.com>
Tested-by: Tan Shaopeng <tan.shaopeng@jp.fujitsu.com>
Link: https://lore.kernel.org/r/20231017002308.134480-4-babu.moger@amd.com
2023-10-17 11:59:14 +02:00
Babu Moger
6846dc1a31 x86/resctrl: Simplify rftype flag definitions
The rftype flags are bitmaps used for adding files under the resctrl
filesystem. Some of these bitmap defines have one extra level of
indirection which is not necessary.

Drop the RF_* defines and simplify the macros.

  [ bp: Massage commit message. ]

Signed-off-by: Babu Moger <babu.moger@amd.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Peter Newman <peternewman@google.com>
Reviewed-by: Tan Shaopeng <tan.shaopeng@jp.fujitsu.com>
Reviewed-by: Fenghua Yu <fenghua.yu@intel.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Tested-by: Peter Newman <peternewman@google.com>
Tested-by: Tan Shaopeng <tan.shaopeng@jp.fujitsu.com>
Link: https://lore.kernel.org/r/20231017002308.134480-3-babu.moger@amd.com
2023-10-17 11:51:16 +02:00
Babu Moger
fe2a20ea0b x86/resctrl: Add multiple tasks to the resctrl group at once
The resctrl task assignment for monitor or control group needs to be
done one at a time. For example:

  $mount -t resctrl resctrl /sys/fs/resctrl/
  $mkdir /sys/fs/resctrl/ctrl_grp1
  $echo 123 > /sys/fs/resctrl/ctrl_grp1/tasks
  $echo 456 > /sys/fs/resctrl/ctrl_grp1/tasks
  $echo 789 > /sys/fs/resctrl/ctrl_grp1/tasks

This is not user-friendly when dealing with hundreds of tasks.

Support multiple task assignment in one command with tasks ids separated
by commas. For example:

  $echo 123,456,789 > /sys/fs/resctrl/ctrl_grp1/tasks

Signed-off-by: Babu Moger <babu.moger@amd.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Peter Newman <peternewman@google.com>
Reviewed-by: Tan Shaopeng <tan.shaopeng@jp.fujitsu.com>
Reviewed-by: Fenghua Yu <fenghua.yu@intel.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Tested-by: Peter Newman <peternewman@google.com>
Tested-by: Tan Shaopeng <tan.shaopeng@jp.fujitsu.com>
Link: https://lore.kernel.org/r/20231017002308.134480-2-babu.moger@amd.com
2023-10-17 11:27:50 +02:00
Joerg Roedel
63e44bc520 x86/sev: Check for user-space IOIO pointing to kernel space
Check the memory operand of INS/OUTS before emulating the instruction.
The #VC exception can get raised from user-space, but the memory operand
can be manipulated to access kernel memory before the emulation actually
begins and after the exception handler has run.

  [ bp: Massage commit message. ]

Fixes: 597cfe4821 ("x86/boot/compressed/64: Setup a GHCB-based VC Exception handler")
Reported-by: Tom Dohrmann <erbse.13@gmx.de>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Cc: <stable@kernel.org>
2023-10-17 10:58:16 +02:00
Arnd Bergmann
acfc788233 vgacon: remove screen_info dependency
The vga console driver is fairly self-contained, and only used by
architectures that explicitly initialize the screen_info settings.

Chance every instance that picks the vga console by setting conswitchp
to call a function instead, and pass a reference to the screen_info
there.

Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Acked-by: Khalid Azzi <khalid@gonehiking.org>
Acked-by: Helge Deller <deller@gmx.de>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/20231009211845.3136536-6-arnd@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-10-17 10:17:02 +02:00