4.19-stable review patch. If anyone has any objections, please let me know.
------------------
From: Borislav Petkov bp@suse.de
commit 60c8144afc287ef09ce8c1230c6aa972659ba1bb upstream.
Currently, the code sets up the thresholding interrupt vector and only then goes about initializing the thresholding banks. Which is wrong, because an early thresholding interrupt would cause a NULL pointer dereference when accessing those banks and prevent the machine from booting.
Therefore, set the thresholding interrupt vector only *after* having initialized the banks successfully.
Fixes: 18807ddb7f88 ("x86/mce/AMD: Reset Threshold Limit after logging error") Reported-by: Rafał Miłecki rafal@milecki.pl Reported-by: John Clemens clemej@gmail.com Signed-off-by: Borislav Petkov bp@suse.de Tested-by: Rafał Miłecki rafal@milecki.pl Tested-by: John Clemens john@deater.net Cc: Aravind Gopalakrishnan aravindksg.lkml@gmail.com Cc: linux-edac@vger.kernel.org Cc: stable@vger.kernel.org Cc: Tony Luck tony.luck@intel.com Cc: x86@kernel.org Cc: Yazen Ghannam Yazen.Ghannam@amd.com Link: https://lkml.kernel.org/r/20181127101700.2964-1-zajec5@gmail.com Link: https://bugzilla.kernel.org/show_bug.cgi?id=201291 Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- arch/x86/kernel/cpu/mcheck/mce_amd.c | 19 ++++++------------- 1 file changed, 6 insertions(+), 13 deletions(-)
--- a/arch/x86/kernel/cpu/mcheck/mce_amd.c +++ b/arch/x86/kernel/cpu/mcheck/mce_amd.c @@ -56,7 +56,7 @@ /* Threshold LVT offset is at MSR0xC0000410[15:12] */ #define SMCA_THR_LVT_OFF 0xF000
-static bool thresholding_en; +static bool thresholding_irq_en;
static const char * const th_names[] = { "load_store", @@ -534,9 +534,8 @@ prepare_threshold_block(unsigned int ban
set_offset: offset = setup_APIC_mce_threshold(offset, new); - - if ((offset == new) && (mce_threshold_vector != amd_threshold_interrupt)) - mce_threshold_vector = amd_threshold_interrupt; + if (offset == new) + thresholding_irq_en = true;
done: mce_threshold_block_init(&b, offset); @@ -1357,9 +1356,6 @@ int mce_threshold_remove_device(unsigned { unsigned int bank;
- if (!thresholding_en) - return 0; - for (bank = 0; bank < mca_cfg.banks; ++bank) { if (!(per_cpu(bank_map, cpu) & (1 << bank))) continue; @@ -1377,9 +1373,6 @@ int mce_threshold_create_device(unsigned struct threshold_bank **bp; int err = 0;
- if (!thresholding_en) - return 0; - bp = per_cpu(threshold_banks, cpu); if (bp) return 0; @@ -1408,9 +1401,6 @@ static __init int threshold_init_device( { unsigned lcpu = 0;
- if (mce_threshold_vector == amd_threshold_interrupt) - thresholding_en = true; - /* to hit CPUs online before the notifier is up */ for_each_online_cpu(lcpu) { int err = mce_threshold_create_device(lcpu); @@ -1419,6 +1409,9 @@ static __init int threshold_init_device( return err; }
+ if (thresholding_irq_en) + mce_threshold_vector = amd_threshold_interrupt; + return 0; } /*