From: Adrian Hunter Date: Mon, 24 Jun 2024 20:10:56 +0000 (+0300) Subject: perf/x86/intel/pt: Fix a topa_entry base address calculation X-Git-Tag: v6.11-rc1~168^2~34 X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=ad97196379d0b8cb24ef3d5006978a6554e6467f;p=thirdparty%2Flinux.git perf/x86/intel/pt: Fix a topa_entry base address calculation topa_entry->base is a bit-field. Bit-fields are not promoted to a 64-bit type, even if the underlying type is 64-bit, and so, if necessary, must be cast to a larger type when calculations are done. Fix a topa_entry->base address calculation by adding a cast. Without the cast, the address was limited to 36-bits i.e. 64GiB. The address calculation is used on systems that do not support Multiple Entry ToPA (only Broadwell), and affects physical addresses on or above 64GiB. Instead of writing to the correct address, the address comprising the first 36 bits would be written to. Intel PT snapshot and sampling modes are not affected. Fixes: 52ca9ced3f70 ("perf/x86/intel/pt: Add Intel PT PMU driver") Reported-by: Dave Hansen Signed-off-by: Adrian Hunter Signed-off-by: Peter Zijlstra (Intel) Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20240624201101.60186-3-adrian.hunter@intel.com --- diff --git a/arch/x86/events/intel/pt.c b/arch/x86/events/intel/pt.c index 14db6d9d318b3..047a2cd5b3fe2 100644 --- a/arch/x86/events/intel/pt.c +++ b/arch/x86/events/intel/pt.c @@ -878,7 +878,7 @@ static void pt_update_head(struct pt *pt) */ static void *pt_buffer_region(struct pt_buffer *buf) { - return phys_to_virt(TOPA_ENTRY(buf->cur, buf->cur_idx)->base << TOPA_SHIFT); + return phys_to_virt((phys_addr_t)TOPA_ENTRY(buf->cur, buf->cur_idx)->base << TOPA_SHIFT); } /**