From: Andi Kleen Date: Wed, 15 Dec 2021 20:40:29 +0000 (-0800) Subject: x86/perf: Avoid warning for Arch LBR without XSAVE X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=8c16dc047b5dd8f7b3bf4584fa75733ea0dde7dc;p=linux.git x86/perf: Avoid warning for Arch LBR without XSAVE Some hypervisors support Arch LBR, but without the LBR XSAVE support. The current Arch LBR init code prints a warning when the xsave size (0) is unexpected. Avoid printing the warning for the "no LBR XSAVE" case. Signed-off-by: Andi Kleen Signed-off-by: Peter Zijlstra (Intel) Link: https://lkml.kernel.org/r/20211215204029.150686-1-ak@linux.intel.com --- diff --git a/arch/x86/events/intel/lbr.c b/arch/x86/events/intel/lbr.c index f8fd255289355..669c2be14784f 100644 --- a/arch/x86/events/intel/lbr.c +++ b/arch/x86/events/intel/lbr.c @@ -1751,6 +1751,9 @@ static bool is_arch_lbr_xsave_available(void) * Check the LBR state with the corresponding software structure. * Disable LBR XSAVES support if the size doesn't match. */ + if (xfeature_size(XFEATURE_LBR) == 0) + return false; + if (WARN_ON(xfeature_size(XFEATURE_LBR) != get_lbr_state_size())) return false;