Re: [PATCH 12/13] x86/jitalloc: prepare to allocate exectuatble memory as ROX
From: Kent Overstreet <kent.overstreet@linux.dev>
Date: 2023-06-01 17:52:34
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On Thu, Jun 01, 2023 at 12:30:50PM +0200, Peter Zijlstra wrote:
On Thu, Jun 01, 2023 at 01:12:56PM +0300, Mike Rapoport wrote:quoted
+static void __init_or_module do_text_poke(void *addr, const void *opcode, size_t len) +{ + if (system_state < SYSTEM_RUNNING) { + text_poke_early(addr, opcode, len); + } else { + mutex_lock(&text_mutex); + text_poke(addr, opcode, len); + mutex_unlock(&text_mutex); + } +}So I don't much like do_text_poke(); why?
Could you share why? I think the impementation sucks but conceptually it's the right idea - create a new temporary mapping to avoid the need for RWX mappings.