kernel.git/arch/arm/kernel/entry-armv.S, branch linux-4.14.y

ARM: 9197/1: spectre-bhb: fix loop8 sequence for Thumb2

2022-05-25T06:41:20Z

[ Upstream commit 3cfb3019979666bdf33a1010147363cf05e0f17b ] In Thumb2, 'b . + 4' produces a branch instruction that uses a narrow encoding, and so it does not jump to the following instruction as expected. So use W(b) instead. Fixes: 6c7cb60bff7a ("ARM: fix Thumb2 regression with Spectre BHB") Signed-off-by: Ard Biesheuvel Signed-off-by: Russell King (Oracle) Signed-off-by: Sasha Levin

ARM: fix Thumb2 regression with Spectre BHB

2022-03-16T11:57:09Z

commit 6c7cb60bff7aec24b834343ff433125f469886a3 upstream. When building for Thumb2, the vectors make use of a local label. Sadly, the Spectre BHB code also uses a local label with the same number which results in the Thumb2 reference pointing at the wrong place. Fix this by changing the number used for the Spectre BHB local label. Fixes: b9baf5c8c5c3 ("ARM: Spectre-BHB workaround") Tested-by: Nathan Chancellor Signed-off-by: Russell King (Oracle) Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman

ARM: Spectre-BHB workaround

2022-03-11T09:13:30Z

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: 9169/1: entry: fix Thumb2 bug in iWMMXt exception handling

2021-12-29T11:17:36Z

commit 8536a5ef886005bc443c2da9b842d69fd3d7647f upstream. The Thumb2 version of the FP exception handling entry code treats the register holding the CP number (R8) differently, resulting in the iWMMXT CP number check to be incorrect. Fix this by unifying the ARM and Thumb2 code paths, and switch the order of the additions of the TI_USED_CP offset and the shifted CP index. Cc: Fixes: b86040a59feb ("Thumb-2: Implementation of the unified start-up and exceptions code") Signed-off-by: Ard Biesheuvel Signed-off-by: Russell King (Oracle) Signed-off-by: Greg Kroah-Hartman

ARM: uaccess: consolidate uaccess asm to asm/uaccess-asm.h

2020-06-03T06:17:58Z

[ Upstream commit 747ffc2fcf969eff9309d7f2d1d61cb8b9e1bb40 ] Consolidate the user access assembly code to asm/uaccess-asm.h. This moves the csdb, check_uaccess, uaccess_mask_range_ptr, uaccess_enable, uaccess_disable, uaccess_save, uaccess_restore macros, and creates two new ones for exception entry and exit - uaccess_entry and uaccess_exit. This makes the uaccess_save and uaccess_restore macros private to asm/uaccess-asm.h. Signed-off-by: Russell King Signed-off-by: Sasha Levin

Merge branches 'fixes' and 'misc' into for-linus

2017-09-09T15:34:41Z

ARM: align .data section

2017-08-14T15:22:55Z

Robert Jarzmik reports that his PXA25x system fails to boot with 4.12, failing at __flush_whole_cache in arch/arm/mm/proc-xscale.S:215: 0xc0019e20 <+0>: ldr r1, [pc, #788] 0xc0019e24 <+4>: ldr r0, [r1] <== here with r1 containing 0xc06f82cd, which is the address of "clean_addr". Examination of the System.map shows: c06f22c8 D user_pmd_table c06f22cc d __warned.19178 c06f22cd d clean_addr indicating that a .data.unlikely section has appeared just before the .data section from proc-xscale.S. According to objdump -h, it appears that our assembly files default their .data alignment to 2**0, which is bad news if the preceding .data section size is not power-of-2 aligned at link time. Add the appropriate .align directives to all assembly files in arch/arm that are missing them where we require an appropriate alignment. Reported-by: Robert Jarzmik Tested-by: Robert Jarzmik Signed-off-by: Russell King

ARM: Prepare for randomized task_struct

2017-06-30T19:00:50Z

With the new task struct randomization, we can run into a build failure for certain random seeds, which will place fields beyond the allow immediate size in the assembly: arch/arm/kernel/entry-armv.S: Assembler messages: arch/arm/kernel/entry-armv.S:803: Error: bad immediate value for offset (4096) Only two constants in asm-offset.h are affected, and I'm changing both of them here to work correctly in all configurations. One more macro has the problem, but is currently unused, so this removes it instead of adding complexity. Suggested-by: Ard Biesheuvel Signed-off-by: Arnd Bergmann [kees: Adjust commit log slightly] Signed-off-by: Kees Cook

ARM: fix address limit restoration for undefined instructions

2016-08-09T21:57:59Z

During boot, sometimes the kernel will test to see if an instruction causes an undefined instruction exception. Unfortunately, the exit path for these exceptions did not restore the address limit, which causes the rootfs mount code to fail. Fix the missing address limit restoration. Tested-by: Guenter Roeck Signed-off-by: Russell King

ARM: save and reset the address limit when entering an exception

2016-07-07T15:01:01Z

When we enter an exception, the current address limit should not apply to the exception context: if the exception context wishes to access kernel space via the user accessors (eg, perf code), it must explicitly request such access. Acked-by: Will Deacon Signed-off-by: Russell King