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platform/x86/intel/ifs: Disable irq during one load stage

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One of the stages in IFS image loading process involves loading individual
chunks (test patterns) from test image file to secure memory.

Driver issues a WRMSR(MSR_AUTHENTICATE_AND_COPY_CHUNK) operation to do
this. This operation can take up to 5 msec, and if an interrupt occurs
in between, the AUTH_AND_COPY_CHUNK u-code implementation aborts the
operation.

Interrupt sources such as NMI or SMI are handled by retrying. Regular
interrupts may occur frequently enough to prevent this operation from ever
completing. Disable irq on local cpu around the aforementioned WRMSR to
allow the operation to complete.

Signed-off-by: Jithu Joseph <jithu.joseph@intel.com>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Reviewed-by: Ashok Raj <ashok.raj@intel.com>
Reviewed-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
Link: https://lore.kernel.org/r/20240412172349.544064-4-jithu.joseph@intel.com
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
This commit is contained in:
Jithu Joseph 2024-04-12 10:23:49 -07:00 committed by Hans de Goede
parent 15b429f4e0
commit bd25a3f5ed
1 changed files with 2 additions and 0 deletions
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2
drivers/platform/x86/intel/ifs/load.c
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@ -233,7 +233,9 @@ static int copy_hashes_authenticate_chunks_gen2(struct device *dev)
chunk_table[0] = starting_chunk_nr + i;
chunk_table[1] = linear_addr;
do {
local_irq_disable();
wrmsrl(MSR_AUTHENTICATE_AND_COPY_CHUNK, (u64)chunk_table);
local_irq_enable();
rdmsrl(MSR_CHUNKS_AUTHENTICATION_STATUS, chunk_status.data);
err_code = chunk_status.error_code;
} while (err_code == AUTH_INTERRUPTED_ERROR && --retry_count);