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-rw-r--r--SOURCES/0001-ARM-fix-__get_user_check-in-case-uaccess_-calls-are-.patch86
1 files changed, 0 insertions, 86 deletions
diff --git a/SOURCES/0001-ARM-fix-__get_user_check-in-case-uaccess_-calls-are-.patch b/SOURCES/0001-ARM-fix-__get_user_check-in-case-uaccess_-calls-are-.patch
deleted file mode 100644
index 283ac06..0000000
--- a/SOURCES/0001-ARM-fix-__get_user_check-in-case-uaccess_-calls-are-.patch
+++ /dev/null
@@ -1,86 +0,0 @@
-From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
-From: Masahiro Yamada <yamada.masahiro@socionext.com>
-Date: Mon, 30 Sep 2019 14:59:25 +0900
-Subject: [PATCH] ARM: fix __get_user_check() in case uaccess_* calls are not
- inlined
-
-KernelCI reports that bcm2835_defconfig is no longer booting since
-commit ac7c3e4ff401 ("compiler: enable CONFIG_OPTIMIZE_INLINING
-forcibly"):
-
- https://lkml.org/lkml/2019/9/26/825
-
-I also received a regression report from Nicolas Saenz Julienne:
-
- https://lkml.org/lkml/2019/9/27/263
-
-This problem has cropped up on arch/arm/config/bcm2835_defconfig
-because it enables CONFIG_CC_OPTIMIZE_FOR_SIZE. The compiler tends
-to prefer not inlining functions with -Os. I was able to reproduce
-it with other boards and defconfig files by manually enabling
-CONFIG_CC_OPTIMIZE_FOR_SIZE.
-
-The __get_user_check() specifically uses r0, r1, r2 registers.
-So, uaccess_save_and_enable() and uaccess_restore() must be inlined
-in order to avoid those registers being overwritten in the callees.
-
-Prior to commit 9012d011660e ("compiler: allow all arches to enable
-CONFIG_OPTIMIZE_INLINING"), the 'inline' marker was always enough for
-inlining functions, except on x86.
-
-Since that commit, all architectures can enable CONFIG_OPTIMIZE_INLINING.
-So, __always_inline is now the only guaranteed way of forcible inlining.
-
-I want to keep as much compiler's freedom as possible about the inlining
-decision. So, I changed the function call order instead of adding
-__always_inline around.
-
-Call uaccess_save_and_enable() before assigning the __p ("r0"), and
-uaccess_restore() after evacuating the __e ("r0").
-
-Fixes: 9012d011660e ("compiler: allow all arches to enable CONFIG_OPTIMIZE_INLINING")
-Reported-by: "kernelci.org bot" <bot@kernelci.org>
-Reported-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
-Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
-Acked-by: Arnd Bergmann <arnd@arndb.de>
-Tested-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
-Tested-by: Fabrizio Castro <fabrizio.castro@bp.renesas.com>
-Tested-by: Geert Uytterhoeven <geert+renesas@glider.be>
----
- arch/arm/include/asm/uaccess.h | 8 +++++---
- 1 file changed, 5 insertions(+), 3 deletions(-)
-
-diff --git a/arch/arm/include/asm/uaccess.h b/arch/arm/include/asm/uaccess.h
-index b5fdd30252f8..d43ceaa78269 100644
---- a/arch/arm/include/asm/uaccess.h
-+++ b/arch/arm/include/asm/uaccess.h
-@@ -195,11 +195,12 @@ extern int __get_user_64t_4(void *);
- #define __get_user_check(x, p) \
- ({ \
- unsigned long __limit = current_thread_info()->addr_limit - 1; \
-+ unsigned int __ua_flags = uaccess_save_and_enable(); \
- register typeof(*(p)) __user *__p asm("r0") = (p); \
- register __inttype(x) __r2 asm("r2"); \
- register unsigned long __l asm("r1") = __limit; \
- register int __e asm("r0"); \
-- unsigned int __ua_flags = uaccess_save_and_enable(); \
-+ unsigned int __err; \
- switch (sizeof(*(__p))) { \
- case 1: \
- if (sizeof((x)) >= 8) \
-@@ -227,9 +228,10 @@ extern int __get_user_64t_4(void *);
- break; \
- default: __e = __get_user_bad(); break; \
- } \
-- uaccess_restore(__ua_flags); \
-+ __err = __e; \
- x = (typeof(*(p))) __r2; \
-- __e; \
-+ uaccess_restore(__ua_flags); \
-+ __err; \
- })
-
- #define get_user(x, p) \
---
-2.28.0
-