kernel/arch/arm/include/asm/domain.h, branch linux-rolling-stable

ARM: 9326/1: make self-contained for ARM

2023-10-05T15:17:05Z

When I compiled the following code for ARM, I encountered numerous errors. [Test Code] #include #include int foo(int *x, int __user *ptr) { return get_user(*x, ptr); } To fix the errors, make some asm headers self-contained: 1. In arch/arm/include/asm/domain.h, include for current_thread_info(). 2. In arch/arm/include/asm/traps.h, remove unneeded __init, and include for asmlinkage. 3. In arch/arm/include/asm/uaccess.h, include for might_fault(). Signed-off-by: Masahiro Yamada Signed-off-by: Russell King (Oracle)

ARM: 9211/1: domain: drop modify_domain()

2022-07-06T21:44:49Z

This function/macro isn't used anywhere in the kernel. The only user was set_fs() and was deleted in the set_fs() removal patch set. Fixes: 8ac6f5d7f84b ("ARM: 9113/1: uaccess: remove set_fs() implementation") Acked-by: Arnd Bergmann Signed-off-by: Linus Walleij Signed-off-by: Russell King (Oracle)

ARM: 8908/1: add __always_inline to functions called from __get_user_check()

2019-10-10T21:23:19Z

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 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. Otherwise, those register assignments would be entirely dropped, according to my analysis of the disassembly. 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 added __always_inline to 4 functions in the call-graph from the __get_user_check() macro. Fixes: 9012d011660e ("compiler: allow all arches to enable CONFIG_OPTIMIZE_INLINING") Reported-by: "kernelci.org bot" Reported-by: Nicolas Saenz Julienne Signed-off-by: Masahiro Yamada Tested-by: Nicolas Saenz Julienne Signed-off-by: Russell King

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500

2019-06-19T15:09:55Z

Based on 2 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation # extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 4122 file(s). Signed-off-by: Thomas Gleixner Reviewed-by: Enrico Weigelt Reviewed-by: Kate Stewart Reviewed-by: Allison Randal Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de Signed-off-by: Greg Kroah-Hartman

ARM: 8851/1: add TUSERCOND() macro for conditional postfix

2019-04-23T16:20:51Z

Unified assembly syntax requires conditionals to be postfixes. TUSER() currently only takes a single argument which then gets appended t (with translation) on every instruction. This fixes a build error when using LLVM's integrated assembler: In file included from kernel/futex.c:72: ./arch/arm/include/asm/futex.h:116:3: error: invalid instruction, did you mean: strt? "2: " TUSER(streq) " %3, [%4]n" ^ :5:4: note: instantiated into assembly here 2: streqt r2, [r4] ^~~~~~ Additionally, for GCC ".syntax unified" for inline assembly. When compiling non-Thumb2 GCC always emits a ".syntax divided" at the beginning of the inline assembly which makes the assembler fail. Since GCC 5 there is the -masm-syntax-unified GCC option which make GCC assume unified syntax asm and hence emits ".syntax unified" even in ARM mode. However, the option is broken since GCC version 6 (see GCC PR88648 [1]). Work around by adding ".syntax unified" as part of the inline assembly. [0] https://gcc.gnu.org/onlinedocs/gcc/ARM-Options.html#index-masm-syntax-unified [1] https://gcc.gnu.org/bugzilla/show_bug.cgi?id=88648 Signed-off-by: Stefan Agner Signed-off-by: Russell King

ARM: 8573/1: domain: move {set,get}_domain under config guard

2016-05-05T18:03:02Z

Recursive undefined instrcution falut is seen with R-class taking an exception. The reson for that is __show_regs() tries to get domain information, but domains is not available on !MMU cores, like R/M class. Fix it by puting {set,get}_domain functions under CONFIG_CPU_CP15_MMU guard and providing stubs for the case where domains is not supported. Signed-off-by: Vladimir Murzin Signed-off-by: Russell King

ARM: domains: add memory dependencies to get_domain/set_domain

2015-09-11T15:08:18Z

We need to have memory dependencies on get_domain/set_domain to avoid the compiler over-optimising these inline assembly instructions. Loads/stores must not be reordered across a set_domain(), so introduce a compiler barrier for that assembly. The value of get_domain() must not be cached across a set_domain(), but we still want to allow the compiler to optimise it away. Introduce a dependency on current_thread_info()->cpu_domain to avoid this; the new memory clobber in set_domain() should therefore cause the compiler to re-load this. The other advantage of using this is we should have its address in the register set already, or very soon after at most call sites. Tested-by: Robert Jarzmik Signed-off-by: Russell King

ARM: software-based priviledged-no-access support

2015-08-26T19:34:24Z

Provide a software-based implementation of the priviledged no access support found in ARMv8.1. Userspace pages are mapped using a different domain number from the kernel and IO mappings. If we switch the user domain to "no access" when we enter the kernel, we can prevent the kernel from touching userspace. However, the kernel needs to be able to access userspace via the various user accessor functions. With the wrapping in the previous patch, we can temporarily enable access when the kernel needs user access, and re-disable it afterwards. This allows us to trap non-intended accesses to userspace, eg, caused by an inadvertent dereference of the LIST_POISON* values, which, with appropriate user mappings setup, can be made to succeed. This in turn can allow use-after-free bugs to be further exploited than would otherwise be possible. Signed-off-by: Russell King

ARM: domains: remove DOMAIN_TABLE

2015-08-21T12:55:53Z

DOMAIN_TABLE is not used; in any case, it aliases to the kernel domain. Remove this definition. Signed-off-by: Russell King

ARM: domains: keep vectors in separate domain

2015-08-21T12:55:53Z

Keep the machine vectors in its own domain to avoid software based user access control from making the vector code inaccessible, and thereby deadlocking the machine. Signed-off-by: Russell King