BMC/Intel-BMC/linux.git/arch/arm/include/asm, branch dev-5.15-intel

ARM: Spectre-BHB: provide empty stub for non-config

2022-03-16T13:23:42+00:00

commit 68453767131a5deec1e8f9ac92a9042f929e585d upstream. When CONFIG_GENERIC_CPU_VULNERABILITIES is not set, references to spectre_v2_update_state() cause a build error, so provide an empty stub for that function when the Kconfig option is not set. Fixes this build error: arm-linux-gnueabi-ld: arch/arm/mm/proc-v7-bugs.o: in function `cpu_v7_bugs_init': proc-v7-bugs.c:(.text+0x52): undefined reference to `spectre_v2_update_state' arm-linux-gnueabi-ld: proc-v7-bugs.c:(.text+0x82): undefined reference to `spectre_v2_update_state' Fixes: b9baf5c8c5c3 ("ARM: Spectre-BHB workaround") Signed-off-by: Randy Dunlap Reported-by: kernel test robot Cc: Russell King Cc: Catalin Marinas Cc: linux-arm-kernel@lists.infradead.org Cc: patches@armlinux.org.uk Acked-by: Russell King (Oracle) Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman

ARM: Do not use NOCROSSREFS directive with ld.lld

2022-03-11T11:22:35+00:00

commit 36168e387fa7d0f1fe0cd5cf76c8cea7aee714fa upstream. ld.lld does not support the NOCROSSREFS directive at the moment, which breaks the build after commit b9baf5c8c5c3 ("ARM: Spectre-BHB workaround"): ld.lld: error: ./arch/arm/kernel/vmlinux.lds:34: AT expected, but got NOCROSSREFS Support for this directive will eventually be implemented, at which point a version check can be added. To avoid breaking the build in the meantime, just define NOCROSSREFS to nothing when using ld.lld, with a link to the issue for tracking. Cc: stable@vger.kernel.org Fixes: b9baf5c8c5c3 ("ARM: Spectre-BHB workaround") Link: https://github.com/ClangBuiltLinux/linux/issues/1609 Signed-off-by: Nathan Chancellor Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman

ARM: fix co-processor register typo

2022-03-11T11:22:35+00:00

commit 33970b031dc4653cc9dc80f2886976706c4c8ef1 upstream. In the recent Spectre BHB patches, there was a typo that is only exposed in certain configurations: mcr p15,0,XX,c7,r5,4 should have been mcr p15,0,XX,c7,c5,4 Reported-by: kernel test robot Fixes: b9baf5c8c5c3 ("ARM: Spectre-BHB workaround") Signed-off-by: Russell King (Oracle) Acked-by: Catalin Marinas Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman

ARM: Spectre-BHB workaround

2022-03-11T11:22:32+00:00

commit b9baf5c8c5c356757f4f9d8180b5e9d234065bc3 upstream. Workaround the Spectre BHB issues for Cortex-A15, Cortex-A57, Cortex-A72, Cortex-A73 and Cortex-A75. We also include Brahma B15 as well to be safe, which is affected by Spectre V2 in the same ways as Cortex-A15. Reviewed-by: Catalin Marinas Signed-off-by: Russell King (Oracle) [changes due to lack of SYSTEM_FREEING_INITMEM - gregkh] Signed-off-by: Greg Kroah-Hartman

ARM: use LOADADDR() to get load address of sections

2022-03-11T11:22:32+00:00

commit 8d9d651ff2270a632e9dc497b142db31e8911315 upstream. Use the linker's LOADADDR() macro to get the load address of the sections, and provide a macro to set the start and end symbols. Acked-by: Catalin Marinas Signed-off-by: Russell King (Oracle) Signed-off-by: Greg Kroah-Hartman

ARM: report Spectre v2 status through sysfs

2022-03-11T11:22:32+00:00

commit 9dd78194a3722fa6712192cdd4f7032d45112a9a upstream. As per other architectures, add support for reporting the Spectre vulnerability status via sysfs CPU. Acked-by: Catalin Marinas Signed-off-by: Russell King (Oracle) Signed-off-by: Greg Kroah-Hartman

ARM: 9180/1: Thumb2: align ALT_UP() sections in modules sufficiently

2022-02-01T16:26:59+00:00

commit 9f80ccda53b9417236945bc7ece4b519037df74d upstream. When building for Thumb2, the .alt.smp.init sections that are emitted by the ALT_UP() patching code may not be 32-bit aligned, even though the fixup_smp_on_up() routine expects that. This results in alignment faults at module load time, which need to be fixed up by the fault handler. So let's align those sections explicitly, and prevent this from occurring. Cc: Signed-off-by: Ard Biesheuvel Signed-off-by: Russell King (Oracle) Signed-off-by: Greg Kroah-Hartman

ARM: 9179/1: uaccess: avoid alignment faults in copy_[from|to]_kernel_nofault

2022-02-01T16:26:59+00:00

commit 15420269b02a63ed8c1841905d8b8b2403246004 upstream. The helpers that are used to implement copy_from_kernel_nofault() and copy_to_kernel_nofault() cast a void* to a pointer to a wider type, which may result in alignment faults on ARM if the compiler decides to use double-word or multiple-word load/store instructions. Only configurations that define CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS=y are affected, given that commit 2423de2e6f4d ("ARM: 9115/1: mm/maccess: fix unaligned copy_{from,to}_kernel_nofault") ensures that dst and src are sufficiently aligned otherwise. So use the unaligned accessors for accessing dst and src in cases where they may be misaligned. Cc: # depends on 2423de2e6f4d Fixes: 2df4c9a741a0 ("ARM: 9112/1: uaccess: add __{get,put}_kernel_nofault") Reviewed-by: Arnd Bergmann Signed-off-by: Ard Biesheuvel Signed-off-by: Russell King (Oracle) Signed-off-by: Greg Kroah-Hartman

efi: Move efifb_setup_from_dmi() prototype from arch headers

2022-01-05T11:42:34+00:00

commit 4bc5e64e6cf37007e436970024e5998ee0935651 upstream. Commit 8633ef82f101 ("drivers/firmware: consolidate EFI framebuffer setup for all arches") made the Generic System Framebuffers (sysfb) driver able to be built on non-x86 architectures. But it left the efifb_setup_from_dmi() function prototype declaration in the architecture specific headers. This could lead to the following compiler warning as reported by the kernel test robot: drivers/firmware/efi/sysfb_efi.c:70:6: warning: no previous prototype for function 'efifb_setup_from_dmi' [-Wmissing-prototypes] void efifb_setup_from_dmi(struct screen_info *si, const char *opt) ^ drivers/firmware/efi/sysfb_efi.c:70:1: note: declare 'static' if the function is not intended to be used outside of this translation unit void efifb_setup_from_dmi(struct screen_info *si, const char *opt) Fixes: 8633ef82f101 ("drivers/firmware: consolidate EFI framebuffer setup for all arches") Reported-by: kernel test robot Cc: # 5.15.x Signed-off-by: Javier Martinez Canillas Acked-by: Thomas Zimmermann Link: https://lore.kernel.org/r/20211126001333.555514-1-javierm@redhat.com Signed-off-by: Ard Biesheuvel Signed-off-by: Greg Kroah-Hartman

ARM: 9132/1: Fix __get_user_check failure with ARM KASAN images

2021-10-19T09:37:35+00:00

ARM: kasan: Fix __get_user_check failure with kasan In macro __get_user_check defined in arch/arm/include/asm/uaccess.h, error code is store in register int __e(r0). When kasan is enabled, assigning value to kernel address might trigger kasan check, which unexpectedly overwrites r0 and causes undefined behavior on arm kasan images. One example is failure in do_futex and results in process soft lockup. Log: watchdog: BUG: soft lockup - CPU#0 stuck for 62946ms! [rs:main Q:Reg:1151] ... (__asan_store4) from (futex_wait_setup+0xf8/0x2b4) (futex_wait_setup) from (futex_wait+0x138/0x394) (futex_wait) from (do_futex+0x164/0xe40) (do_futex) from (sys_futex_time32+0x178/0x230) (sys_futex_time32) from (ret_fast_syscall+0x0/0x50) The soft lockup happens in function futex_wait_setup. The reason is function get_futex_value_locked always return EINVAL, thus pc jump back to retry label and causes looping. This line in function get_futex_value_locked ret = __get_user(*dest, from); is expanded to *dest = (typeof(*(p))) __r2; , in macro __get_user_check. Writing to pointer dest triggers kasan check and overwrites the return value of __get_user_x function. The assembly code of get_futex_value_locked in kernel/futex.c: ... c01f6dc8: eb0b020e bl c04b7608 <__get_user_4> // "x = (typeof(*(p))) __r2;" triggers kasan check and r0 is overwritten c01f6dCc: e1a00007 mov r0, r7 c01f6dd0: e1a05002 mov r5, r2 c01f6dd4: eb04f1e6 bl c0333574 <__asan_store4> c01f6dd8: e5875000 str r5, [r7] // save ret value of __get_user(*dest, from), which is dest address now c01f6ddc: e1a05000 mov r5, r0 ... // checking return value of __get_user failed c01f6e00: e3550000 cmp r5, #0 ... c01f6e0c: 01a00005 moveq r0, r5 // assign return value to EINVAL c01f6e10: 13e0000d mvnne r0, #13 Return value is the destination address of get_user thus certainly non-zero, so get_futex_value_locked always return EINVAL. Fix it by using a tmp vairable to store the error code before the assignment. This fix has no effects to non-kasan images thanks to compiler optimization. It only affects cases that overwrite r0 due to kasan check. This should fix bug discussed in Link: [1] https://lore.kernel.org/linux-arm-kernel/0ef7c2a5-5d8b-c5e0-63fa-31693fd4495c@gmail.com/ Fixes: 421015713b30 ("ARM: 9017/2: Enable KASan for ARM") Signed-off-by: Lexi Shao Signed-off-by: Russell King (Oracle)