wireguard-linux/arch/powerpc/kernel/head_40x.S, branch jd/unified-crypt-queue

powerpc/32: save DEAR/DAR before calling handle_page_fault

2020-01-26T11:15:09Z

handle_page_fault() is the only function that save DAR/DEAR itself. Save DAR/DEAR before calling handle_page_fault() to prepare for VMAP stack which will require to save even before. Signed-off-by: Christophe Leroy Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/3a4d58d378091086f00fde42b59610c80289e120.1576916812.git.christophe.leroy@c-s.fr

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152

2019-05-30T18:26:32Z

Based on 1 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 as published by the free software foundation either version 2 of the license or at your option any later version extracted by the scancode license scanner the SPDX license identifier GPL-2.0-or-later has been chosen to replace the boilerplate/reference in 3029 file(s). Signed-off-by: Thomas Gleixner Reviewed-by: Allison Randal Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de Signed-off-by: Greg Kroah-Hartman

powerpc/32: implement fast entry for syscalls on non BOOKE

2019-05-02T15:20:27Z

This patch implements a fast entry for syscalls. Syscalls don't have to preserve non volatile registers except LR. This patch then implement a fast entry for syscalls, where volatile registers get clobbered. As this entry is dedicated to syscall it always sets MSR_EE and warns in case MSR_EE was previously off It also assumes that the call is always from user, system calls are unexpected from kernel. The overall series improves null_syscall selftest by 12,5% on an 83xx and by 17% on a 8xx. Signed-off-by: Christophe Leroy Signed-off-by: Michael Ellerman

powerpc/32: get rid of COPY_EE in exception entry

2019-05-02T15:20:27Z

EXC_XFER_TEMPLATE() is not called with COPY_EE anymore so we can get rid of copyee parameters and related COPY_EE and NOCOPY macros. Suggested-by: Benjamin Herrenschmidt [splited out from benh RFC patch] Signed-off-by: Christophe Leroy Signed-off-by: Michael Ellerman

powerpc/32: Enter exceptions with MSR_EE unset

2019-05-02T15:20:27Z

All exceptions handlers know when to reenable interrupts, so it is safer to enter all of them with MSR_EE unset, except for syscalls. Suggested-by: Benjamin Herrenschmidt [splited out from benh RFC patch] Signed-off-by: Christophe Leroy Signed-off-by: Michael Ellerman

powerpc/32: enter syscall with MSR_EE inconditionaly set

2019-05-02T15:20:27Z

syscalls are expected to be entered with MSR_EE set. Lets make it inconditional by forcing MSR_EE on syscalls. This patch adds EXC_XFER_SYS for that. Suggested-by: Benjamin Herrenschmidt [splited out from benh RFC patch] Signed-off-by: Christophe Leroy Signed-off-by: Michael Ellerman

powerpc/40x: Refactor exception entry macros by using head_32.h

2019-05-02T15:20:27Z

Refactor exception entry macros by using the ones defined in head_32.h Signed-off-by: Christophe Leroy Signed-off-by: Michael Ellerman

powerpc/40x: Split and rename NORMAL_EXCEPTION_PROLOG

2019-05-02T15:20:27Z

This patch splits NORMAL_EXCEPTION_PROLOG in the same way as in head_8xx.S and head_32.S and renames it EXCEPTION_PROLOG() as well to match head_32.h Signed-off-by: Christophe Leroy Signed-off-by: Michael Ellerman

powerpc/40x: add exception frame marker

2019-05-02T15:20:27Z

This patch adds STACK_FRAME_REGS_MARKER in the stack at exception entry in order to see interrupts in call traces as below: [ 0.013964] Call Trace: [ 0.014014] [c0745db0] [c007a9d4] tick_periodic.constprop.5+0xd8/0x104 (unreliable) [ 0.014086] [c0745dc0] [c007aa20] tick_handle_periodic+0x20/0x9c [ 0.014181] [c0745de0] [c0009cd0] timer_interrupt+0xa0/0x264 [ 0.014258] [c0745e10] [c000e484] ret_from_except+0x0/0x14 [ 0.014390] --- interrupt: 901 at console_unlock.part.7+0x3f4/0x528 [ 0.014390] LR = console_unlock.part.7+0x3f0/0x528 [ 0.014455] [c0745ee0] [c0050334] console_unlock.part.7+0x114/0x528 (unreliable) [ 0.014542] [c0745f30] [c00524e0] register_console+0x3d8/0x44c [ 0.014625] [c0745f60] [c0675aac] cpm_uart_console_init+0x18/0x2c [ 0.014709] [c0745f70] [c06614f4] console_init+0x114/0x1cc [ 0.014795] [c0745fb0] [c0658b68] start_kernel+0x300/0x3d8 [ 0.014864] [c0745ff0] [c00022cc] start_here+0x44/0x98 Signed-off-by: Christophe Leroy Signed-off-by: Michael Ellerman

powerpc/40x: Don't use SPRN_SPRG_SCRATCH2 in EXCEPTION_PROLOG

2019-05-02T15:20:27Z

Unlike said in the comment, r1 is not reused by the critical exception handler, as it uses a dedicated critirq_ctx stack. Decrementing r1 early is then unneeded. Should the above be valid, the code is crap buggy anyway as r1 gets some intermediate values that would jeopardise the whole process (for instance after mfspr r1,SPRN_SPRG_THREAD) Using SPRN_SPRG_SCRATCH2 to save r1 is then not needed, r11 can be used instead. This avoids one mtspr and one mfspr and makes the prolog closer to what's done on 6xx and 8xx. Signed-off-by: Christophe Leroy Signed-off-by: Michael Ellerman