OpenCloudOS-Kernel/arch/powerpc/kernel/head_booke.h

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License cleanup: add SPDX GPL-2.0 license identifier to files with no license Many source files in the tree are missing licensing information, which makes it harder for compliance tools to determine the correct license. By default all files without license information are under the default license of the kernel, which is GPL version 2. Update the files which contain no license information with the 'GPL-2.0' SPDX license identifier. The SPDX identifier is a legally binding shorthand, which can be used instead of the full boiler plate text. This patch is based on work done by Thomas Gleixner and Kate Stewart and Philippe Ombredanne. How this work was done: Patches were generated and checked against linux-4.14-rc6 for a subset of the use cases: - file had no licensing information it it. - file was a */uapi/* one with no licensing information in it, - file was a */uapi/* one with existing licensing information, Further patches will be generated in subsequent months to fix up cases where non-standard license headers were used, and references to license had to be inferred by heuristics based on keywords. The analysis to determine which SPDX License Identifier to be applied to a file was done in a spreadsheet of side by side results from of the output of two independent scanners (ScanCode & Windriver) producing SPDX tag:value files created by Philippe Ombredanne. Philippe prepared the base worksheet, and did an initial spot review of a few 1000 files. The 4.13 kernel was the starting point of the analysis with 60,537 files assessed. Kate Stewart did a file by file comparison of the scanner results in the spreadsheet to determine which SPDX license identifier(s) to be applied to the file. She confirmed any determination that was not immediately clear with lawyers working with the Linux Foundation. Criteria used to select files for SPDX license identifier tagging was: - Files considered eligible had to be source code files. - Make and config files were included as candidates if they contained >5 lines of source - File already had some variant of a license header in it (even if <5 lines). All documentation files were explicitly excluded. The following heuristics were used to determine which SPDX license identifiers to apply. - when both scanners couldn't find any license traces, file was considered to have no license information in it, and the top level COPYING file license applied. For non */uapi/* files that summary was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 11139 and resulted in the first patch in this series. If that file was a */uapi/* path one, it was "GPL-2.0 WITH Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 WITH Linux-syscall-note 930 and resulted in the second patch in this series. - if a file had some form of licensing information in it, and was one of the */uapi/* ones, it was denoted with the Linux-syscall-note if any GPL family license was found in the file or had no licensing in it (per prior point). Results summary: SPDX license identifier # files ---------------------------------------------------|------ GPL-2.0 WITH Linux-syscall-note 270 GPL-2.0+ WITH Linux-syscall-note 169 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17 LGPL-2.1+ WITH Linux-syscall-note 15 GPL-1.0+ WITH Linux-syscall-note 14 ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5 LGPL-2.0+ WITH Linux-syscall-note 4 LGPL-2.1 WITH Linux-syscall-note 3 ((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3 ((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1 and that resulted in the third patch in this series. - when the two scanners agreed on the detected license(s), that became the concluded license(s). - when there was disagreement between the two scanners (one detected a license but the other didn't, or they both detected different licenses) a manual inspection of the file occurred. - In most cases a manual inspection of the information in the file resulted in a clear resolution of the license that should apply (and which scanner probably needed to revisit its heuristics). - When it was not immediately clear, the license identifier was confirmed with lawyers working with the Linux Foundation. - If there was any question as to the appropriate license identifier, the file was flagged for further research and to be revisited later in time. In total, over 70 hours of logged manual review was done on the spreadsheet to determine the SPDX license identifiers to apply to the source files by Kate, Philippe, Thomas and, in some cases, confirmation by lawyers working with the Linux Foundation. Kate also obtained a third independent scan of the 4.13 code base from FOSSology, and compared selected files where the other two scanners disagreed against that SPDX file, to see if there was new insights. The Windriver scanner is based on an older version of FOSSology in part, so they are related. Thomas did random spot checks in about 500 files from the spreadsheets for the uapi headers and agreed with SPDX license identifier in the files he inspected. For the non-uapi files Thomas did random spot checks in about 15000 files. In initial set of patches against 4.14-rc6, 3 files were found to have copy/paste license identifier errors, and have been fixed to reflect the correct identifier. Additionally Philippe spent 10 hours this week doing a detailed manual inspection and review of the 12,461 patched files from the initial patch version early this week with: - a full scancode scan run, collecting the matched texts, detected license ids and scores - reviewing anything where there was a license detected (about 500+ files) to ensure that the applied SPDX license was correct - reviewing anything where there was no detection but the patch license was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied SPDX license was correct This produced a worksheet with 20 files needing minor correction. This worksheet was then exported into 3 different .csv files for the different types of files to be modified. These .csv files were then reviewed by Greg. Thomas wrote a script to parse the csv files and add the proper SPDX tag to the file, in the format that the file expected. This script was further refined by Greg based on the output to detect more types of files automatically and to distinguish between header and source .c files (which need different comment types.) Finally Greg ran the script using the .csv files to generate the patches. Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-01 22:07:57 +08:00
/* SPDX-License-Identifier: GPL-2.0 */
#ifndef __HEAD_BOOKE_H__
#define __HEAD_BOOKE_H__
#include <asm/ptrace.h> /* for STACK_FRAME_REGS_MARKER */
#include <asm/kvm_asm.h>
#include <asm/kvm_booke_hv_asm.h>
#ifdef __ASSEMBLY__
/*
* Macros used for common Book-e exception handling
*/
#define SET_IVOR(vector_number, vector_label) \
li r26,vector_label@l; \
mtspr SPRN_IVOR##vector_number,r26; \
sync
powerpc/44x: Support for 256KB PAGE_SIZE This patch adds support for 256KB pages on ppc44x-based boards. For simplification of implementation with 256KB pages we still assume 2-level paging. As a side effect this leads to wasting extra memory space reserved for PTE tables: only 1/4 of pages allocated for PTEs are actually used. But this may be an acceptable trade-off to achieve the high performance we have with big PAGE_SIZEs in some applications (e.g. RAID). Also with 256KB PAGE_SIZE we increase THREAD_SIZE up to 32KB to minimize the risk of stack overflows in the cases of on-stack arrays, which size depends on the page size (e.g. multipage BIOs, NTFS, etc.). With 256KB PAGE_SIZE we need to decrease the PKMAP_ORDER at least down to 9, otherwise all high memory (2 ^ 10 * PAGE_SIZE == 256MB) we'll be occupied by PKMAP addresses leaving no place for vmalloc. We do not separate PKMAP_ORDER for 256K from 16K/64K PAGE_SIZE here; actually that value of 10 in support for 16K/64K had been selected rather intuitively. Thus now for all cases of PAGE_SIZE on ppc44x (including the default, 4KB, one) we have 512 pages for PKMAP. Because ELF standard supports only page sizes up to 64K, then you should use binutils later than 2.17.50.0.3 with '-zmax-page-size' set to 256K for building applications, which are to be run with the 256KB-page sized kernel. If using the older binutils, then you should patch them like follows: --- binutils/bfd/elf32-ppc.c.orig +++ binutils/bfd/elf32-ppc.c -#define ELF_MAXPAGESIZE 0x10000 +#define ELF_MAXPAGESIZE 0x40000 One more restriction we currently have with 256KB page sizes is inability to use shmem safely, so, for now, the 256KB is available only if you turn the CONFIG_SHMEM option off (another variant is to use BROKEN). Though, if you need shmem with 256KB pages, you can always remove the !SHMEM dependency in 'config PPC_256K_PAGES', and use the workaround available here: http://lkml.org/lkml/2008/12/19/20 Signed-off-by: Yuri Tikhonov <yur@emcraft.com> Signed-off-by: Ilya Yanok <yanok@emcraft.com> Signed-off-by: Josh Boyer <jwboyer@linux.vnet.ibm.com>
2009-01-29 09:40:44 +08:00
#if (THREAD_SHIFT < 15)
#define ALLOC_STACK_FRAME(reg, val) \
addi reg,reg,val
#else
#define ALLOC_STACK_FRAME(reg, val) \
addis reg,reg,val@ha; \
addi reg,reg,val@l
#endif
/*
* Macro used to get to thread save registers.
* Note that entries 0-3 are used for the prolog code, and the remaining
* entries are available for specific exception use in the event a handler
* requires more than 4 scratch registers.
*/
#define THREAD_NORMSAVE(offset) (THREAD_NORMSAVES + (offset * 4))
#ifdef CONFIG_PPC_FSL_BOOK3E
#define BOOKE_CLEAR_BTB(reg) \
START_BTB_FLUSH_SECTION \
BTB_FLUSH(reg) \
END_BTB_FLUSH_SECTION
#else
#define BOOKE_CLEAR_BTB(reg)
#endif
#define NORMAL_EXCEPTION_PROLOG(trapno, intno) \
mtspr SPRN_SPRG_WSCRATCH0, r10; /* save one register */ \
mfspr r10, SPRN_SPRG_THREAD; \
stw r11, THREAD_NORMSAVE(0)(r10); \
stw r13, THREAD_NORMSAVE(2)(r10); \
mfcr r13; /* save CR in r13 for now */\
mfspr r11, SPRN_SRR1; \
DO_KVM BOOKE_INTERRUPT_##intno SPRN_SRR1; \
andi. r11, r11, MSR_PR; /* check whether user or kernel */\
LOAD_REG_IMMEDIATE(r11, MSR_KERNEL); \
mtmsr r11; \
mr r11, r1; \
beq 1f; \
BOOKE_CLEAR_BTB(r11) \
/* if from user, start at top of this thread's kernel stack */ \
lwz r11, TASK_STACK - THREAD(r10); \
ALLOC_STACK_FRAME(r11, THREAD_SIZE); \
1 : subi r11, r11, INT_FRAME_SIZE; /* Allocate exception frame */ \
stw r13, _CCR(r11); /* save various registers */ \
stw r12,GPR12(r11); \
stw r9,GPR9(r11); \
mfspr r13, SPRN_SPRG_RSCRATCH0; \
stw r13, GPR10(r11); \
lwz r12, THREAD_NORMSAVE(0)(r10); \
stw r12,GPR11(r11); \
lwz r13, THREAD_NORMSAVE(2)(r10); /* restore r13 */ \
mflr r10; \
stw r10,_LINK(r11); \
mfspr r12,SPRN_SRR0; \
stw r1, GPR1(r11); \
mfspr r9,SPRN_SRR1; \
stw r1, 0(r11); \
mr r1, r11; \
rlwinm r9,r9,0,14,12; /* clear MSR_WE (necessary?) */\
COMMON_EXCEPTION_PROLOG_END trapno
.macro COMMON_EXCEPTION_PROLOG_END trapno
stw r0,GPR0(r1)
lis r10, STACK_FRAME_REGS_MARKER@ha /* exception frame marker */
addi r10, r10, STACK_FRAME_REGS_MARKER@l
stw r10, 8(r1)
li r10, \trapno
stw r10,_TRAP(r1)
SAVE_GPRS(3, 8, r1)
SAVE_NVGPRS(r1)
stw r2,GPR2(r1)
stw r12,_NIP(r1)
stw r9,_MSR(r1)
mfctr r10
mfspr r2,SPRN_SPRG_THREAD
stw r10,_CTR(r1)
tovirt(r2, r2)
mfspr r10,SPRN_XER
addi r2, r2, -THREAD
stw r10,_XER(r1)
addi r3,r1,STACK_FRAME_OVERHEAD
.endm
.macro prepare_transfer_to_handler
#ifdef CONFIG_E500
andi. r12,r9,MSR_PR
bne 777f
bl prepare_transfer_to_handler
777:
#endif
.endm
.macro SYSCALL_ENTRY trapno intno srr1
mfspr r10, SPRN_SPRG_THREAD
#ifdef CONFIG_KVM_BOOKE_HV
BEGIN_FTR_SECTION
mtspr SPRN_SPRG_WSCRATCH0, r10
stw r11, THREAD_NORMSAVE(0)(r10)
stw r13, THREAD_NORMSAVE(2)(r10)
mfcr r13 /* save CR in r13 for now */
mfspr r11, SPRN_SRR1
mtocrf 0x80, r11 /* check MSR[GS] without clobbering reg */
bf 3, 1975f
b kvmppc_handler_\intno\()_\srr1
1975:
mr r12, r13
lwz r13, THREAD_NORMSAVE(2)(r10)
FTR_SECTION_ELSE
mfcr r12
ALT_FTR_SECTION_END_IFSET(CPU_FTR_EMB_HV)
#else
mfcr r12
#endif
mfspr r9, SPRN_SRR1
BOOKE_CLEAR_BTB(r11)
mr r11, r1
lwz r1, TASK_STACK - THREAD(r10)
rlwinm r12,r12,0,4,2 /* Clear SO bit in CR */
ALLOC_STACK_FRAME(r1, THREAD_SIZE - INT_FRAME_SIZE)
stw r12, _CCR(r1)
mfspr r12,SPRN_SRR0
stw r12,_NIP(r1)
b transfer_to_syscall /* jump to handler */
.endm
/* To handle the additional exception priority levels on 40x and Book-E
* processors we allocate a stack per additional priority level.
*
* On 40x critical is the only additional level
* On 44x/e500 we have critical and machine check
*
* Additionally we reserve a SPRG for each priority level so we can free up a
* GPR to use as the base for indirect access to the exception stacks. This
* is necessary since the MMU is always on, for Book-E parts, and the stacks
* are offset from KERNELBASE.
*
* There is some space optimization to be had here if desired. However
* to allow for a common kernel with support for debug exceptions either
* going to critical or their own debug level we aren't currently
* providing configurations that micro-optimize space usage.
*/
#define MC_STACK_BASE mcheckirq_ctx
#define CRIT_STACK_BASE critirq_ctx
/* only on e500mc */
#define DBG_STACK_BASE dbgirq_ctx
#ifdef CONFIG_SMP
#define BOOKE_LOAD_EXC_LEVEL_STACK(level) \
mfspr r8,SPRN_PIR; \
slwi r8,r8,2; \
addis r8,r8,level##_STACK_BASE@ha; \
lwz r8,level##_STACK_BASE@l(r8); \
addi r8,r8,THREAD_SIZE - INT_FRAME_SIZE;
#else
#define BOOKE_LOAD_EXC_LEVEL_STACK(level) \
lis r8,level##_STACK_BASE@ha; \
lwz r8,level##_STACK_BASE@l(r8); \
addi r8,r8,THREAD_SIZE - INT_FRAME_SIZE;
#endif
/*
* Exception prolog for critical/machine check exceptions. This is a
* little different from the normal exception prolog above since a
* critical/machine check exception can potentially occur at any point
* during normal exception processing. Thus we cannot use the same SPRG
* registers as the normal prolog above. Instead we use a portion of the
* critical/machine check exception stack at low physical addresses.
*/
#define EXC_LEVEL_EXCEPTION_PROLOG(exc_level, trapno, intno, exc_level_srr0, exc_level_srr1) \
mtspr SPRN_SPRG_WSCRATCH_##exc_level,r8; \
BOOKE_LOAD_EXC_LEVEL_STACK(exc_level);/* r8 points to the exc_level stack*/ \
stw r9,GPR9(r8); /* save various registers */\
mfcr r9; /* save CR in r9 for now */\
stw r10,GPR10(r8); \
stw r11,GPR11(r8); \
stw r9,_CCR(r8); /* save CR on stack */\
mfspr r11,exc_level_srr1; /* check whether user or kernel */\
DO_KVM BOOKE_INTERRUPT_##intno exc_level_srr1; \
BOOKE_CLEAR_BTB(r10) \
andi. r11,r11,MSR_PR; \
LOAD_REG_IMMEDIATE(r11, MSR_KERNEL & ~(MSR_ME|MSR_DE|MSR_CE)); \
mtmsr r11; \
mfspr r11,SPRN_SPRG_THREAD; /* if from user, start at top of */\
lwz r11, TASK_STACK - THREAD(r11); /* this thread's kernel stack */\
addi r11,r11,THREAD_SIZE - INT_FRAME_SIZE; /* allocate stack frame */\
beq 1f; \
/* COMING FROM USER MODE */ \
stw r9,_CCR(r11); /* save CR */\
lwz r10,GPR10(r8); /* copy regs from exception stack */\
lwz r9,GPR9(r8); \
stw r10,GPR10(r11); \
lwz r10,GPR11(r8); \
stw r9,GPR9(r11); \
stw r10,GPR11(r11); \
b 2f; \
/* COMING FROM PRIV MODE */ \
1: mr r11, r8; \
2: mfspr r8,SPRN_SPRG_RSCRATCH_##exc_level; \
stw r12,GPR12(r11); /* save various registers */\
mflr r10; \
stw r10,_LINK(r11); \
mfspr r12,SPRN_DEAR; /* save DEAR and ESR in the frame */\
stw r12,_DEAR(r11); /* since they may have had stuff */\
mfspr r9,SPRN_ESR; /* in them at the point where the */\
stw r9,_ESR(r11); /* exception was taken */\
mfspr r12,exc_level_srr0; \
stw r1,GPR1(r11); \
mfspr r9,exc_level_srr1; \
stw r1,0(r11); \
mr r1,r11; \
rlwinm r9,r9,0,14,12; /* clear MSR_WE (necessary?) */\
COMMON_EXCEPTION_PROLOG_END trapno
#define SAVE_xSRR(xSRR) \
mfspr r0,SPRN_##xSRR##0; \
stw r0,_##xSRR##0(r1); \
mfspr r0,SPRN_##xSRR##1; \
stw r0,_##xSRR##1(r1)
.macro SAVE_MMU_REGS
#ifdef CONFIG_PPC_BOOK3E_MMU
mfspr r0,SPRN_MAS0
stw r0,MAS0(r1)
mfspr r0,SPRN_MAS1
stw r0,MAS1(r1)
mfspr r0,SPRN_MAS2
stw r0,MAS2(r1)
mfspr r0,SPRN_MAS3
stw r0,MAS3(r1)
mfspr r0,SPRN_MAS6
stw r0,MAS6(r1)
#ifdef CONFIG_PHYS_64BIT
mfspr r0,SPRN_MAS7
stw r0,MAS7(r1)
#endif /* CONFIG_PHYS_64BIT */
#endif /* CONFIG_PPC_BOOK3E_MMU */
#ifdef CONFIG_44x
mfspr r0,SPRN_MMUCR
stw r0,MMUCR(r1)
#endif
.endm
#define CRITICAL_EXCEPTION_PROLOG(trapno, intno) \
EXC_LEVEL_EXCEPTION_PROLOG(CRIT, trapno+2, intno, SPRN_CSRR0, SPRN_CSRR1)
#define DEBUG_EXCEPTION_PROLOG(trapno) \
EXC_LEVEL_EXCEPTION_PROLOG(DBG, trapno+8, DEBUG, SPRN_DSRR0, SPRN_DSRR1)
#define MCHECK_EXCEPTION_PROLOG(trapno) \
EXC_LEVEL_EXCEPTION_PROLOG(MC, trapno+4, MACHINE_CHECK, \
SPRN_MCSRR0, SPRN_MCSRR1)
/*
* Guest Doorbell -- this is a bit odd in that uses GSRR0/1 despite
* being delivered to the host. This exception can only happen
* inside a KVM guest -- so we just handle up to the DO_KVM rather
* than try to fit this into one of the existing prolog macros.
*/
#define GUEST_DOORBELL_EXCEPTION \
START_EXCEPTION(GuestDoorbell); \
mtspr SPRN_SPRG_WSCRATCH0, r10; /* save one register */ \
mfspr r10, SPRN_SPRG_THREAD; \
stw r11, THREAD_NORMSAVE(0)(r10); \
mfspr r11, SPRN_SRR1; \
stw r13, THREAD_NORMSAVE(2)(r10); \
mfcr r13; /* save CR in r13 for now */\
DO_KVM BOOKE_INTERRUPT_GUEST_DBELL SPRN_GSRR1; \
trap
/*
* Exception vectors.
*/
#define START_EXCEPTION(label) \
.align 5; \
label:
#define EXCEPTION(n, intno, label, hdlr) \
START_EXCEPTION(label); \
NORMAL_EXCEPTION_PROLOG(n, intno); \
prepare_transfer_to_handler; \
bl hdlr; \
b interrupt_return
#define CRITICAL_EXCEPTION(n, intno, label, hdlr) \
START_EXCEPTION(label); \
CRITICAL_EXCEPTION_PROLOG(n, intno); \
SAVE_MMU_REGS; \
SAVE_xSRR(SRR); \
prepare_transfer_to_handler; \
bl hdlr; \
b ret_from_crit_exc
#define MCHECK_EXCEPTION(n, label, hdlr) \
START_EXCEPTION(label); \
MCHECK_EXCEPTION_PROLOG(n); \
mfspr r5,SPRN_ESR; \
stw r5,_ESR(r11); \
SAVE_xSRR(DSRR); \
SAVE_xSRR(CSRR); \
SAVE_MMU_REGS; \
SAVE_xSRR(SRR); \
prepare_transfer_to_handler; \
bl hdlr; \
b ret_from_mcheck_exc
/* Check for a single step debug exception while in an exception
* handler before state has been saved. This is to catch the case
* where an instruction that we are trying to single step causes
* an exception (eg ITLB/DTLB miss) and thus the first instruction of
* the exception handler generates a single step debug exception.
*
* If we get a debug trap on the first instruction of an exception handler,
* we reset the MSR_DE in the _exception handler's_ MSR (the debug trap is
* a critical exception, so we are using SPRN_CSRR1 to manipulate the MSR).
* The exception handler was handling a non-critical interrupt, so it will
* save (and later restore) the MSR via SPRN_CSRR1, which will still have
* the MSR_DE bit set.
*/
#define DEBUG_DEBUG_EXCEPTION \
START_EXCEPTION(DebugDebug); \
DEBUG_EXCEPTION_PROLOG(2000); \
\
/* \
* If there is a single step or branch-taken exception in an \
* exception entry sequence, it was probably meant to apply to \
* the code where the exception occurred (since exception entry \
* doesn't turn off DE automatically). We simulate the effect \
* of turning off DE on entry to an exception handler by turning \
* off DE in the DSRR1 value and clearing the debug status. \
*/ \
mfspr r10,SPRN_DBSR; /* check single-step/branch taken */ \
andis. r10,r10,(DBSR_IC|DBSR_BT)@h; \
beq+ 2f; \
\
lis r10,interrupt_base@h; /* check if exception in vectors */ \
ori r10,r10,interrupt_base@l; \
cmplw r12,r10; \
blt+ 2f; /* addr below exception vectors */ \
\
lis r10,interrupt_end@h; \
ori r10,r10,interrupt_end@l; \
cmplw r12,r10; \
bgt+ 2f; /* addr above exception vectors */ \
\
/* here it looks like we got an inappropriate debug exception. */ \
1: rlwinm r9,r9,0,~MSR_DE; /* clear DE in the CDRR1 value */ \
lis r10,(DBSR_IC|DBSR_BT)@h; /* clear the IC event */ \
mtspr SPRN_DBSR,r10; \
/* restore state and get out */ \
lwz r10,_CCR(r11); \
lwz r0,GPR0(r11); \
lwz r1,GPR1(r11); \
mtcrf 0x80,r10; \
mtspr SPRN_DSRR0,r12; \
mtspr SPRN_DSRR1,r9; \
lwz r9,GPR9(r11); \
lwz r12,GPR12(r11); \
mtspr SPRN_SPRG_WSCRATCH_DBG,r8; \
BOOKE_LOAD_EXC_LEVEL_STACK(DBG); /* r8 points to the debug stack */ \
lwz r10,GPR10(r8); \
lwz r11,GPR11(r8); \
mfspr r8,SPRN_SPRG_RSCRATCH_DBG; \
\
PPC_RFDI; \
b .; \
\
/* continue normal handling for a debug exception... */ \
2: mfspr r4,SPRN_DBSR; \
stw r4,_ESR(r11); /* DebugException takes DBSR in _ESR */\
SAVE_xSRR(CSRR); \
SAVE_MMU_REGS; \
SAVE_xSRR(SRR); \
prepare_transfer_to_handler; \
bl DebugException; \
b ret_from_debug_exc
#define DEBUG_CRIT_EXCEPTION \
START_EXCEPTION(DebugCrit); \
CRITICAL_EXCEPTION_PROLOG(2000,DEBUG); \
\
/* \
* If there is a single step or branch-taken exception in an \
* exception entry sequence, it was probably meant to apply to \
* the code where the exception occurred (since exception entry \
* doesn't turn off DE automatically). We simulate the effect \
* of turning off DE on entry to an exception handler by turning \
* off DE in the CSRR1 value and clearing the debug status. \
*/ \
mfspr r10,SPRN_DBSR; /* check single-step/branch taken */ \
andis. r10,r10,(DBSR_IC|DBSR_BT)@h; \
beq+ 2f; \
\
lis r10,interrupt_base@h; /* check if exception in vectors */ \
ori r10,r10,interrupt_base@l; \
cmplw r12,r10; \
blt+ 2f; /* addr below exception vectors */ \
\
lis r10,interrupt_end@h; \
ori r10,r10,interrupt_end@l; \
cmplw r12,r10; \
bgt+ 2f; /* addr above exception vectors */ \
\
/* here it looks like we got an inappropriate debug exception. */ \
1: rlwinm r9,r9,0,~MSR_DE; /* clear DE in the CSRR1 value */ \
lis r10,(DBSR_IC|DBSR_BT)@h; /* clear the IC event */ \
mtspr SPRN_DBSR,r10; \
/* restore state and get out */ \
lwz r10,_CCR(r11); \
lwz r0,GPR0(r11); \
lwz r1,GPR1(r11); \
mtcrf 0x80,r10; \
mtspr SPRN_CSRR0,r12; \
mtspr SPRN_CSRR1,r9; \
lwz r9,GPR9(r11); \
lwz r12,GPR12(r11); \
mtspr SPRN_SPRG_WSCRATCH_CRIT,r8; \
BOOKE_LOAD_EXC_LEVEL_STACK(CRIT); /* r8 points to the debug stack */ \
lwz r10,GPR10(r8); \
lwz r11,GPR11(r8); \
mfspr r8,SPRN_SPRG_RSCRATCH_CRIT; \
\
rfci; \
b .; \
\
/* continue normal handling for a critical exception... */ \
2: mfspr r4,SPRN_DBSR; \
stw r4,_ESR(r11); /* DebugException takes DBSR in _ESR */\
SAVE_MMU_REGS; \
SAVE_xSRR(SRR); \
prepare_transfer_to_handler; \
bl DebugException; \
b ret_from_crit_exc
#define DATA_STORAGE_EXCEPTION \
START_EXCEPTION(DataStorage) \
NORMAL_EXCEPTION_PROLOG(0x300, DATA_STORAGE); \
mfspr r5,SPRN_ESR; /* Grab the ESR and save it */ \
stw r5,_ESR(r11); \
mfspr r4,SPRN_DEAR; /* Grab the DEAR */ \
stw r4, _DEAR(r11); \
prepare_transfer_to_handler; \
bl do_page_fault; \
b interrupt_return
powerpc/32e: Ignore ESR in instruction storage interrupt handler A e5500 machine running a 32-bit kernel sometimes hangs at boot, seemingly going into an infinite loop of instruction storage interrupts. The ESR (Exception Syndrome Register) has a value of 0x800000 (store) when this happens, which is likely set by a previous store. An instruction TLB miss interrupt would then leave ESR unchanged, and if no PTE exists it calls directly to the instruction storage interrupt handler without changing ESR. access_error() does not cause a segfault due to a store to a read-only vma because is_exec is true. Most subsequent fault handling does not check for a write fault on a read-only vma, and might do strange things like create a writeable PTE or call page_mkwrite on a read only vma or file. It's not clear what happens here to cause the infinite faulting in this case, a fault handler failure or low level PTE or TLB handling. In any case this can be fixed by having the instruction storage interrupt zero regs->dsisr rather than storing the ESR value to it. Fixes: a01a3f2ddbcd ("powerpc: remove arguments from fault handler functions") Cc: stable@vger.kernel.org # v5.12+ Reported-by: Jacques de Laval <jacques.delaval@protonmail.com> Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Tested-by: Jacques de Laval <jacques.delaval@protonmail.com> Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20211028133043.4159501-1-npiggin@gmail.com
2021-10-28 21:30:43 +08:00
/*
* Instruction TLB Error interrupt handlers may call InstructionStorage
* directly without clearing ESR, so the ESR at this point may be left over
* from a prior interrupt.
*
* In any case, do_page_fault for BOOK3E does not use ESR and always expects
* dsisr to be 0. ESR_DST from a prior store in particular would confuse fault
* handling.
*/
#define INSTRUCTION_STORAGE_EXCEPTION \
START_EXCEPTION(InstructionStorage) \
powerpc/32e: Ignore ESR in instruction storage interrupt handler A e5500 machine running a 32-bit kernel sometimes hangs at boot, seemingly going into an infinite loop of instruction storage interrupts. The ESR (Exception Syndrome Register) has a value of 0x800000 (store) when this happens, which is likely set by a previous store. An instruction TLB miss interrupt would then leave ESR unchanged, and if no PTE exists it calls directly to the instruction storage interrupt handler without changing ESR. access_error() does not cause a segfault due to a store to a read-only vma because is_exec is true. Most subsequent fault handling does not check for a write fault on a read-only vma, and might do strange things like create a writeable PTE or call page_mkwrite on a read only vma or file. It's not clear what happens here to cause the infinite faulting in this case, a fault handler failure or low level PTE or TLB handling. In any case this can be fixed by having the instruction storage interrupt zero regs->dsisr rather than storing the ESR value to it. Fixes: a01a3f2ddbcd ("powerpc: remove arguments from fault handler functions") Cc: stable@vger.kernel.org # v5.12+ Reported-by: Jacques de Laval <jacques.delaval@protonmail.com> Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Tested-by: Jacques de Laval <jacques.delaval@protonmail.com> Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20211028133043.4159501-1-npiggin@gmail.com
2021-10-28 21:30:43 +08:00
NORMAL_EXCEPTION_PROLOG(0x400, INST_STORAGE); \
li r5,0; /* Store 0 in regs->esr (dsisr) */ \
stw r5,_ESR(r11); \
powerpc/32e: Ignore ESR in instruction storage interrupt handler A e5500 machine running a 32-bit kernel sometimes hangs at boot, seemingly going into an infinite loop of instruction storage interrupts. The ESR (Exception Syndrome Register) has a value of 0x800000 (store) when this happens, which is likely set by a previous store. An instruction TLB miss interrupt would then leave ESR unchanged, and if no PTE exists it calls directly to the instruction storage interrupt handler without changing ESR. access_error() does not cause a segfault due to a store to a read-only vma because is_exec is true. Most subsequent fault handling does not check for a write fault on a read-only vma, and might do strange things like create a writeable PTE or call page_mkwrite on a read only vma or file. It's not clear what happens here to cause the infinite faulting in this case, a fault handler failure or low level PTE or TLB handling. In any case this can be fixed by having the instruction storage interrupt zero regs->dsisr rather than storing the ESR value to it. Fixes: a01a3f2ddbcd ("powerpc: remove arguments from fault handler functions") Cc: stable@vger.kernel.org # v5.12+ Reported-by: Jacques de Laval <jacques.delaval@protonmail.com> Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Tested-by: Jacques de Laval <jacques.delaval@protonmail.com> Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20211028133043.4159501-1-npiggin@gmail.com
2021-10-28 21:30:43 +08:00
stw r12, _DEAR(r11); /* Set regs->dear (dar) to SRR0 */ \
prepare_transfer_to_handler; \
bl do_page_fault; \
b interrupt_return
#define ALIGNMENT_EXCEPTION \
START_EXCEPTION(Alignment) \
NORMAL_EXCEPTION_PROLOG(0x600, ALIGNMENT); \
mfspr r4,SPRN_DEAR; /* Grab the DEAR and save it */ \
stw r4,_DEAR(r11); \
prepare_transfer_to_handler; \
bl alignment_exception; \
REST_NVGPRS(r1); \
b interrupt_return
#define PROGRAM_EXCEPTION \
START_EXCEPTION(Program) \
NORMAL_EXCEPTION_PROLOG(0x700, PROGRAM); \
mfspr r4,SPRN_ESR; /* Grab the ESR and save it */ \
stw r4,_ESR(r11); \
prepare_transfer_to_handler; \
bl program_check_exception; \
REST_NVGPRS(r1); \
b interrupt_return
#define DECREMENTER_EXCEPTION \
START_EXCEPTION(Decrementer) \
NORMAL_EXCEPTION_PROLOG(0x900, DECREMENTER); \
lis r0,TSR_DIS@h; /* Setup the DEC interrupt mask */ \
mtspr SPRN_TSR,r0; /* Clear the DEC interrupt */ \
prepare_transfer_to_handler; \
bl timer_interrupt; \
b interrupt_return
#define FP_UNAVAILABLE_EXCEPTION \
START_EXCEPTION(FloatingPointUnavailable) \
NORMAL_EXCEPTION_PROLOG(0x800, FP_UNAVAIL); \
beq 1f; \
bl load_up_fpu; /* if from user, just load it up */ \
b fast_exception_return; \
1: prepare_transfer_to_handler; \
bl kernel_fp_unavailable_exception; \
b interrupt_return
#endif /* __ASSEMBLY__ */
#endif /* __HEAD_BOOKE_H__ */