linux.git/arch/x86/kernel/cpu/microcode/intel.c, branch v4.19

x86/microcode: Update the new microcode revision unconditionally

2018-09-02T12:10:54+00:00

Handle the case where microcode gets loaded on the BSP's hyperthread
sibling first and the boot_cpu_data's microcode revision doesn't get
updated because of early exit due to the siblings sharing a microcode
engine.

For that, simply write the updated revision on all CPUs unconditionally.

Signed-off-by: Filippo Sironi 
Signed-off-by: Borislav Petkov 
Signed-off-by: Thomas Gleixner 
Cc: prarit@redhat.com
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/1533050970-14385-1-git-send-email-sironi@amazon.de

x86/microcode: Make sure boot_cpu_data.microcode is up-to-date

2018-09-02T12:10:54+00:00

When preparing an MCE record for logging, boot_cpu_data.microcode is used
to read out the microcode revision on the box.

However, on systems where late microcode update has happened, the microcode
revision output in a MCE log record is wrong because
boot_cpu_data.microcode is not updated when the microcode gets updated.

But, the microcode revision saved in boot_cpu_data's microcode member
should be kept up-to-date, regardless, for consistency.

Make it so.

Fixes: fa94d0c6e0f3 ("x86/MCE: Save microcode revision in machine check records")
Signed-off-by: Prarit Bhargava 
Signed-off-by: Borislav Petkov 
Signed-off-by: Thomas Gleixner 
Cc: Tony Luck 
Cc: sironi@amazon.de
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/20180731112739.32338-1-prarit@redhat.com

x86/microcode/intel: Fix memleak in save_microcode_patch()

2018-06-22T12:42:59+00:00

Free useless ucode_patch entry when it's replaced.

[ bp: Drop the memfree_patch() two-liner. ]

Signed-off-by: Zhenzhong Duan 
Signed-off-by: Borislav Petkov 
Signed-off-by: Thomas Gleixner 
Cc: Srinivas REDDY Eeda 
Link: http://lkml.kernel.org/r/888102f0-fd22-459d-b090-a1bd8a00cb2b@default

x86/microcode/intel: Save microcode patch unconditionally

2018-04-24T07:48:22+00:00

save_mc_for_early() was a no-op on !CONFIG_HOTPLUG_CPU but the
generic_load_microcode() path saves the microcode patches it has found into
the cache of patches which is used for late loading too. Regardless of
whether CPU hotplug is used or not.

Make the saving unconditional so that late loading can find the proper
patch.

Reported-by: Vitezslav Samel 
Signed-off-by: Borislav Petkov 
Signed-off-by: Thomas Gleixner 
Tested-by: Vitezslav Samel 
Tested-by: Ashok Raj 
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/20180418081140.GA2439@pc11.op.pod.cz
Link: https://lkml.kernel.org/r/20180421081930.15741-1-bp@alien8.de

x86/microcode: Attempt late loading only when new microcode is present

2018-03-16T19:55:51+00:00

Return UCODE_NEW from the scanning functions to denote that new microcode
was found and only then attempt the expensive synchronization dance.

Reported-by: Emanuel Czirai 
Signed-off-by: Borislav Petkov 
Signed-off-by: Thomas Gleixner 
Tested-by: Emanuel Czirai 
Tested-by: Ashok Raj 
Tested-by: Tom Lendacky 
Link: https://lkml.kernel.org/r/20180314183615.17629-1-bp@alien8.de

x86/microcode/intel: Look into the patch cache first

2018-03-08T09:19:26+00:00

The cache might contain a newer patch - look in there first.

A follow-on change will make sure newest patches are loaded into the
cache of microcode patches.

Signed-off-by: Borislav Petkov 
Signed-off-by: Thomas Gleixner 
Tested-by: Tom Lendacky 
Tested-by: Ashok Raj 
Cc: Arjan Van De Ven 
Link: https://lkml.kernel.org/r/20180228102846.13447-6-bp@alien8.de

x86/microcode/intel: Writeback and invalidate caches before updating microcode

2018-03-08T09:19:25+00:00

Updating microcode is less error prone when caches have been flushed and
depending on what exactly the microcode is updating. For example, some
of the issues around certain Broadwell parts can be addressed by doing a
full cache flush.

[ Borislav: Massage it and use native_wbinvd() in both cases. ]

Signed-off-by: Ashok Raj 
Signed-off-by: Borislav Petkov 
Signed-off-by: Thomas Gleixner 
Tested-by: Tom Lendacky 
Tested-by: Ashok Raj 
Cc: Arjan Van De Ven 
Link: http://lkml.kernel.org/r/1519352533-15992-3-git-send-email-ashok.raj@intel.com
Link: https://lkml.kernel.org/r/20180228102846.13447-4-bp@alien8.de

x86/microcode/intel: Check microcode revision before updating sibling threads

2018-03-08T09:19:25+00:00

After updating microcode on one of the threads of a core, the other
thread sibling automatically gets the update since the microcode
resources on a hyperthreaded core are shared between the two threads.

Check the microcode revision on the CPU before performing a microcode
update and thus save us the WRMSR 0x79 because it is a particularly
expensive operation.

[ Borislav: Massage changelog and coding style. ]

Signed-off-by: Ashok Raj 
Signed-off-by: Borislav Petkov 
Signed-off-by: Thomas Gleixner 
Tested-by: Tom Lendacky 
Tested-by: Ashok Raj 
Cc: Arjan Van De Ven 
Link: http://lkml.kernel.org/r/1519352533-15992-2-git-send-email-ashok.raj@intel.com
Link: https://lkml.kernel.org/r/20180228102846.13447-3-bp@alien8.de

x86/microcode: Propagate return value from updating functions

2018-02-17T07:43:55+00:00

... so that callers can know when microcode was updated and act
accordingly.

Tested-by: Ashok Raj 
Signed-off-by: Borislav Petkov 
Reviewed-by: Ashok Raj 
Cc: Andy Lutomirski 
Cc: Arjan van de Ven 
Cc: Borislav Petkov 
Cc: Dan Williams 
Cc: Dave Hansen 
Cc: David Woodhouse 
Cc: Greg Kroah-Hartman 
Cc: Josh Poimboeuf 
Cc: Linus Torvalds 
Cc: Peter Zijlstra 
Cc: Thomas Gleixner 
Link: http://lkml.kernel.org/r/20180216112640.11554-2-bp@alien8.de
Signed-off-by: Ingo Molnar

x86/cpu: Change type of x86_cache_size variable to unsigned int

2018-02-15T00:15:53+00:00

Currently, x86_cache_size is of type int, which makes no sense as we
will never have a valid cache size equal or less than 0. So instead of
initializing this variable to -1, it can perfectly be initialized to 0
and use it as an unsigned variable instead.

Suggested-by: Thomas Gleixner 
Signed-off-by: Gustavo A. R. Silva 
Cc: Borislav Petkov 
Cc: Linus Torvalds 
Cc: Peter Zijlstra 
Addresses-Coverity-ID: 1464429
Link: http://lkml.kernel.org/r/20180213192208.GA26414@embeddedor.com
Signed-off-by: Ingo Molnar