4.4-stable patches

added patches:
	vmlinux.lds.h-add-pgo-and-autofdo-input-sections.patch

diff --git a/queue-4.4/series b/queue-4.4/series
index 2e293b868823e0f2f15eb26a9aaa24cc19c1887d..e545840797b7d199e4aefb863aec6ca1789a9386 100644 (file)
--- a/queue-4.4/series
+++ b/queue-4.4/series
@@ -7,3 +7,4 @@ scsi-target-fix-xcopy-naa-identifier-lookup.patch
 powerpc-fix-incorrect-stw-ux-u-x-instructions-in-__s.patch
 net-ip-always-refragment-ip-defragmented-packets.patch
 net-fix-pmtu-check-in-nopmtudisc-mode.patch
+vmlinux.lds.h-add-pgo-and-autofdo-input-sections.patch

diff --git a/queue-4.4/vmlinux.lds.h-add-pgo-and-autofdo-input-sections.patch b/queue-4.4/vmlinux.lds.h-add-pgo-and-autofdo-input-sections.patch
new file mode 100644 (file)
index 0000000..0df86b4
--- /dev/null
+++ b/queue-4.4/vmlinux.lds.h-add-pgo-and-autofdo-input-sections.patch
@@ -0,0 +1,87 @@
+From foo@baz Fri Jan 15 10:45:42 AM CET 2021
+From: Nick Desaulniers <ndesaulniers@google.com>
+Date: Fri, 21 Aug 2020 12:42:47 -0700
+Subject: vmlinux.lds.h: Add PGO and AutoFDO input sections
+
+From: Nick Desaulniers <ndesaulniers@google.com>
+
+commit eff8728fe69880d3f7983bec3fb6cea4c306261f upstream.
+
+Basically, consider .text.{hot|unlikely|unknown}.* part of .text, too.
+
+When compiling with profiling information (collected via PGO
+instrumentations or AutoFDO sampling), Clang will separate code into
+.text.hot, .text.unlikely, or .text.unknown sections based on profiling
+information. After D79600 (clang-11), these sections will have a
+trailing `.` suffix, ie.  .text.hot., .text.unlikely., .text.unknown..
+
+When using -ffunction-sections together with profiling infomation,
+either explicitly (FGKASLR) or implicitly (LTO), code may be placed in
+sections following the convention:
+.text.hot.<foo>, .text.unlikely.<bar>, .text.unknown.<baz>
+where <foo>, <bar>, and <baz> are functions.  (This produces one section
+per function; we generally try to merge these all back via linker script
+so that we don't have 50k sections).
+
+For the above cases, we need to teach our linker scripts that such
+sections might exist and that we'd explicitly like them grouped
+together, otherwise we can wind up with code outside of the
+_stext/_etext boundaries that might not be mapped properly for some
+architectures, resulting in boot failures.
+
+If the linker script is not told about possible input sections, then
+where the section is placed as output is a heuristic-laiden mess that's
+non-portable between linkers (ie. BFD and LLD), and has resulted in many
+hard to debug bugs.  Kees Cook is working on cleaning this up by adding
+--orphan-handling=warn linker flag used in ARCH=powerpc to additional
+architectures. In the case of linker scripts, borrowing from the Zen of
+Python: explicit is better than implicit.
+
+Also, ld.bfd's internal linker script considers .text.hot AND
+.text.hot.* to be part of .text, as well as .text.unlikely and
+.text.unlikely.*. I didn't see support for .text.unknown.*, and didn't
+see Clang producing such code in our kernel builds, but I see code in
+LLVM that can produce such section names if profiling information is
+missing. That may point to a larger issue with generating or collecting
+profiles, but I would much rather be safe and explicit than have to
+debug yet another issue related to orphan section placement.
+
+Reported-by: Jian Cai <jiancai@google.com>
+Suggested-by: Fāng-ruì Sòng <maskray@google.com>
+Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
+Signed-off-by: Kees Cook <keescook@chromium.org>
+Signed-off-by: Ingo Molnar <mingo@kernel.org>
+Tested-by: Luis Lozano <llozano@google.com>
+Tested-by: Manoj Gupta <manojgupta@google.com>
+Acked-by: Kees Cook <keescook@chromium.org>
+Cc: linux-arch@vger.kernel.org
+Cc: stable@vger.kernel.org
+Link: https://sourceware.org/git/?p=binutils-gdb.git;a=commitdiff;h=add44f8d5c5c05e08b11e033127a744d61c26aee
+Link: https://sourceware.org/git/?p=binutils-gdb.git;a=commitdiff;h=1de778ed23ce7492c523d5850c6c6dbb34152655
+Link: https://reviews.llvm.org/D79600
+Link: https://bugs.chromium.org/p/chromium/issues/detail?id=1084760
+Link: https://lore.kernel.org/r/20200821194310.3089815-7-keescook@chromium.org
+
+Debugged-by: Luis Lozano <llozano@google.com>
+[nc: Fix conflicts around lack of TEXT_MAIN, NOINSTR_TEXT, and
+     .text..refcount]
+Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ include/asm-generic/vmlinux.lds.h |    5 ++++-
+ 1 file changed, 4 insertions(+), 1 deletion(-)
+
+--- a/include/asm-generic/vmlinux.lds.h
++++ b/include/asm-generic/vmlinux.lds.h
+@@ -422,7 +422,10 @@
+  * during second ld run in second ld pass when generating System.map */
+ #define TEXT_TEXT                                                     \
+               ALIGN_FUNCTION();                                       \
+-              *(.text.hot .text .text.fixup .text.unlikely)           \
++              *(.text.hot .text.hot.*)                                \
++              *(.text .text.fixup)                                    \
++              *(.text.unlikely .text.unlikely.*)                      \
++              *(.text.unknown .text.unknown.*)                        \
+               *(.ref.text)                                            \
+       MEM_KEEP(init.text)                                             \
+       MEM_KEEP(exit.text)                                             \