From: Steven Rostedt Date: Tue, 27 Oct 2009 17:15:11 +0000 (-0400) Subject: tracing: allow to change permissions for text with dynamic ftrace enabled X-Git-Tag: v2.6.33-rc1~374^2~26 X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=883242dd0e5faaba041528a9a99f483f2a656c83;p=pandora-kernel.git tracing: allow to change permissions for text with dynamic ftrace enabled The commit 74e081797bd9d2a7d8005fe519e719df343a2ba8 x86-64: align RODATA kernel section to 2MB with CONFIG_DEBUG_RODATA prevents text sections from becoming read/write using set_memory_rw. The dynamic ftrace changes all text pages to read/write just before converting the calls to tracing to nops, and vice versa. I orginally just added a flag to allow this transaction when ftrace did the change, but I also found that when the CPA testing was running it would remove the read/write as well, and ftrace does not do the text conversion on boot up, and the CPA changes caused the dynamic tracer to fail on self tests. The current solution I have is to simply not to prevent change_page_attr from setting the RW bit for kernel text pages. Reported-by: Ingo Molnar Cc: Suresh Siddha Cc: H. Peter Anvin Signed-off-by: Steven Rostedt --- Reading git-diff-tree failed