From: Jinjie Ruan Date: Mon, 8 Jul 2024 03:28:46 +0000 (+0800) Subject: riscv: Fix fp alignment bug in perf_callchain_user() X-Git-Tag: v6.10.13~254 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=09210bb3a0f4b6d599c494017a38774b563bac4d;p=thirdparty%2Fkernel%2Fstable.git riscv: Fix fp alignment bug in perf_callchain_user() [ Upstream commit 22ab08955ea13be04a8efd20cc30890e0afaa49c ] The standard RISC-V calling convention said: "The stack grows downward and the stack pointer is always kept 16-byte aligned". So perf_callchain_user() should check whether 16-byte aligned for fp. Link: https://riscv.org/wp-content/uploads/2015/01/riscv-calling.pdf Fixes: dbeb90b0c1eb ("riscv: Add perf callchain support") Signed-off-by: Jinjie Ruan Cc: Björn Töpel Link: https://lore.kernel.org/r/20240708032847.2998158-2-ruanjinjie@huawei.com Signed-off-by: Palmer Dabbelt Signed-off-by: Sasha Levin --- diff --git a/arch/riscv/kernel/perf_callchain.c b/arch/riscv/kernel/perf_callchain.c index 3348a61de7d99..2932791e93882 100644 --- a/arch/riscv/kernel/perf_callchain.c +++ b/arch/riscv/kernel/perf_callchain.c @@ -62,7 +62,7 @@ void perf_callchain_user(struct perf_callchain_entry_ctx *entry, perf_callchain_store(entry, regs->epc); fp = user_backtrace(entry, fp, regs->ra); - while (fp && !(fp & 0x3) && entry->nr < entry->max_stack) + while (fp && !(fp & 0x7) && entry->nr < entry->max_stack) fp = user_backtrace(entry, fp, 0); }