freebsd-dev/sys/amd64/include/md_var.h

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/*-
* SPDX-License-Identifier: BSD-3-Clause
*
* Copyright (c) 1995 Bruce D. Evans.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the author nor the names of contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
1999-08-28 01:08:13 +00:00
* $FreeBSD$
*/
#ifndef _MACHINE_MD_VAR_H_
#define _MACHINE_MD_VAR_H_
#include <x86/x86_var.h>
Lower the amd64 shared page, which contains the signal trampoline, from the top of user memory to one page lower on machines with the Ryzen (AMD Family 17h) CPU. This pushes ps_strings and the stack down by one page as well. On Ryzen there is some sort of interaction between code running at the top of user memory address space and interrupts that can cause FreeBSD to either hang or silently reset. This sounds similar to the problem found with DragonFly BSD that was fixed with this commit: https://gitweb.dragonflybsd.org/dragonfly.git/commitdiff/b48dd28447fc8ef62fbc963accd301557fd9ac20 but our signal trampoline location was already lower than the address that DragonFly moved their signal trampoline to. It also does not appear to be related to SMT as described here: https://www.phoronix.com/forums/forum/hardware/processors-memory/955368-some-ryzen-linux-users-are-facing-issues-with-heavy-compilation-loads?p=955498#post955498 "Hi, Matt Dillon here. Yes, I did find what I believe to be a hardware issue with Ryzen related to concurrent operations. In a nutshell, for any given hyperthread pair, if one hyperthread is in a cpu-bound loop of any kind (can be in user mode), and the other hyperthread is returning from an interrupt via IRETQ, the hyperthread issuing the IRETQ can stall indefinitely until the other hyperthread with the cpu-bound loop pauses (aka HLT until next interrupt). After this situation occurs, the system appears to destabilize. The situation does not occur if the cpu-bound loop is on a different core than the core doing the IRETQ. The %rip the IRETQ returns to (e.g. userland %rip address) matters a *LOT*. The problem occurs more often with high %rip addresses such as near the top of the user stack, which is where DragonFly's signal trampoline traditionally resides. So a user program taking a signal on one thread while another thread is cpu-bound can cause this behavior. Changing the location of the signal trampoline makes it more difficult to reproduce the problem. I have not been because the able to completely mitigate it. When a cpu-thread stalls in this manner it appears to stall INSIDE the microcode for IRETQ. It doesn't make it to the return pc, and the cpu thread cannot take any IPIs or other hardware interrupts while in this state." since the system instability has been observed on FreeBSD with SMT disabled. Interrupts to appear to play a factor since running a signal-intensive process on the first CPU core, which handles most of the interrupts on my machine, is far more likely to trigger the problem than running such a process on any other core. Also lower sv_maxuser to prevent a malicious user from using mmap() to load and execute code in the top page of user memory that was made available when the shared page was moved down. Make the same changes to the 64-bit Linux emulator. PR: 219399 Reported by: nbe@renzel.net Reviewed by: kib Reviewed by: dchagin (previous version) Tested by: nbe@renzel.net (earlier version) MFC after: 2 weeks Differential Revision: https://reviews.freebsd.org/D11780
2017-08-02 01:43:35 +00:00
extern uint64_t *vm_page_dump;
extern int hw_lower_amd64_sharedpage;
extern int hw_ibrs_disable;
extern int hw_ssb_disable;
extern int nmi_flush_l1d_sw;
extern int syscall_ret_l1d_flush_mode;
Add pci_early function to detect Intel stolen memory. On some Intel devices BIOS does not properly reserve memory (called "stolen memory") for the GPU. If the stolen memory is claimed by the OS, functions that depend on stolen memory (like frame buffer compression) can't be used. A function called pci_early_quirks that is called before the virtual memory system is started was added. In Linux, this PCI early quirks function iterates through all PCI slots to check for any device that require quirks. While this more generic solution is preferable I only ported the Intel graphics specific parts because I think my implementation would be too similar to Linux GPL'd solution after looking at the Linux code too much. The code regarding Intel graphics stolen memory was ported from Linux. In the case of Intel graphics stolen memory this pci_early_quirks will read the stolen memory base and size from north bridge registers. The values are stored in global variables that is later read by linuxkpi_gplv2. Linuxkpi stores these values in a Linux-specific structure that is read by the drm driver. Relevant linuxkpi code is here: https://github.com/FreeBSDDesktop/kms-drm/blob/drm-v4.16/linuxkpi/gplv2/src/linux_compat.c#L37 For now, only amd64 arch is suppor ted since that is the only arch supported by the new drm drivers. I was told that Intel GPUs are always located on 0:2:0 so these values are hard coded for now. Note that the structure and early execution of the detection code is not required in its current form, but we expect that the code will be added shortly which fixes the potential BIOS bugs by reserving the stolen range in phys_avail[]. This must be done as early as possible to avoid conflicts with the potential usage of the memory in kernel. Submitted by: Johannes Lundberg <johalun0@gmail.com> Reviewed by: bwidawsk, imp MFC after: 1 week Differential revision: https://reviews.freebsd.org/D16719 Differential revision: https://reviews.freebsd.org/D17775
2018-10-31 23:17:00 +00:00
extern vm_paddr_t intel_graphics_stolen_base;
extern vm_paddr_t intel_graphics_stolen_size;
/*
* The file "conf/ldscript.amd64" defines the symbol "kernphys". Its
* value is the physical address at which the kernel is loaded.
*/
extern char kernphys[];
Add support for the extended FPU states on amd64, both for native 64bit and 32bit ABIs. As a side-effect, it enables AVX on capable CPUs. In particular: - Query the CPU support for XSAVE, list of the supported extensions and the required size of FPU save area. The hw.use_xsave tunable is provided for disabling XSAVE, and hw.xsave_mask may be used to select the enabled extensions. - Remove the FPU save area from PCB and dynamically allocate the (run-time sized) user save area on the top of the kernel stack, right above the PCB. Reorganize the thread0 PCB initialization to postpone it after BSP is queried for save area size. - The dumppcb, stoppcbs and susppcbs now do not carry the FPU state as well. FPU state is only useful for suspend, where it is saved in dynamically allocated suspfpusave area. - Use XSAVE and XRSTOR to save/restore FPU state, if supported and enabled. - Define new mcontext_t flag _MC_HASFPXSTATE, indicating that mcontext_t has a valid pointer to out-of-struct extended FPU state. Signal handlers are supplied with stack-allocated fpu state. The sigreturn(2) and setcontext(2) syscall honour the flag, allowing the signal handlers to inspect and manipilate extended state in the interrupted context. - The getcontext(2) never returns extended state, since there is no place in the fixed-sized mcontext_t to place variable-sized save area. And, since mcontext_t is embedded into ucontext_t, makes it impossible to fix in a reasonable way. Instead of extending getcontext(2) syscall, provide a sysarch(2) facility to query extended FPU state. - Add ptrace(2) support for getting and setting extended state; while there, implement missed PT_I386_{GET,SET}XMMREGS for 32bit binaries. - Change fpu_kern KPI to not expose struct fpu_kern_ctx layout to consumers, making it opaque. Internally, struct fpu_kern_ctx now contains a space for the extended state. Convert in-kernel consumers of fpu_kern KPI both on i386 and amd64. First version of the support for AVX was submitted by Tim Bird <tim.bird am sony com> on behalf of Sony. This version was written from scratch. Tested by: pho (previous version), Yamagi Burmeister <lists yamagi org> MFC after: 1 month
2012-01-21 17:45:27 +00:00
struct savefpu;
Lower the amd64 shared page, which contains the signal trampoline, from the top of user memory to one page lower on machines with the Ryzen (AMD Family 17h) CPU. This pushes ps_strings and the stack down by one page as well. On Ryzen there is some sort of interaction between code running at the top of user memory address space and interrupts that can cause FreeBSD to either hang or silently reset. This sounds similar to the problem found with DragonFly BSD that was fixed with this commit: https://gitweb.dragonflybsd.org/dragonfly.git/commitdiff/b48dd28447fc8ef62fbc963accd301557fd9ac20 but our signal trampoline location was already lower than the address that DragonFly moved their signal trampoline to. It also does not appear to be related to SMT as described here: https://www.phoronix.com/forums/forum/hardware/processors-memory/955368-some-ryzen-linux-users-are-facing-issues-with-heavy-compilation-loads?p=955498#post955498 "Hi, Matt Dillon here. Yes, I did find what I believe to be a hardware issue with Ryzen related to concurrent operations. In a nutshell, for any given hyperthread pair, if one hyperthread is in a cpu-bound loop of any kind (can be in user mode), and the other hyperthread is returning from an interrupt via IRETQ, the hyperthread issuing the IRETQ can stall indefinitely until the other hyperthread with the cpu-bound loop pauses (aka HLT until next interrupt). After this situation occurs, the system appears to destabilize. The situation does not occur if the cpu-bound loop is on a different core than the core doing the IRETQ. The %rip the IRETQ returns to (e.g. userland %rip address) matters a *LOT*. The problem occurs more often with high %rip addresses such as near the top of the user stack, which is where DragonFly's signal trampoline traditionally resides. So a user program taking a signal on one thread while another thread is cpu-bound can cause this behavior. Changing the location of the signal trampoline makes it more difficult to reproduce the problem. I have not been because the able to completely mitigate it. When a cpu-thread stalls in this manner it appears to stall INSIDE the microcode for IRETQ. It doesn't make it to the return pc, and the cpu thread cannot take any IPIs or other hardware interrupts while in this state." since the system instability has been observed on FreeBSD with SMT disabled. Interrupts to appear to play a factor since running a signal-intensive process on the first CPU core, which handles most of the interrupts on my machine, is far more likely to trigger the problem than running such a process on any other core. Also lower sv_maxuser to prevent a malicious user from using mmap() to load and execute code in the top page of user memory that was made available when the shared page was moved down. Make the same changes to the 64-bit Linux emulator. PR: 219399 Reported by: nbe@renzel.net Reviewed by: kib Reviewed by: dchagin (previous version) Tested by: nbe@renzel.net (earlier version) MFC after: 2 weeks Differential Revision: https://reviews.freebsd.org/D11780
2017-08-02 01:43:35 +00:00
struct sysentvec;
void amd64_conf_fast_syscall(void);
void amd64_db_resume_dbreg(void);
Lower the amd64 shared page, which contains the signal trampoline, from the top of user memory to one page lower on machines with the Ryzen (AMD Family 17h) CPU. This pushes ps_strings and the stack down by one page as well. On Ryzen there is some sort of interaction between code running at the top of user memory address space and interrupts that can cause FreeBSD to either hang or silently reset. This sounds similar to the problem found with DragonFly BSD that was fixed with this commit: https://gitweb.dragonflybsd.org/dragonfly.git/commitdiff/b48dd28447fc8ef62fbc963accd301557fd9ac20 but our signal trampoline location was already lower than the address that DragonFly moved their signal trampoline to. It also does not appear to be related to SMT as described here: https://www.phoronix.com/forums/forum/hardware/processors-memory/955368-some-ryzen-linux-users-are-facing-issues-with-heavy-compilation-loads?p=955498#post955498 "Hi, Matt Dillon here. Yes, I did find what I believe to be a hardware issue with Ryzen related to concurrent operations. In a nutshell, for any given hyperthread pair, if one hyperthread is in a cpu-bound loop of any kind (can be in user mode), and the other hyperthread is returning from an interrupt via IRETQ, the hyperthread issuing the IRETQ can stall indefinitely until the other hyperthread with the cpu-bound loop pauses (aka HLT until next interrupt). After this situation occurs, the system appears to destabilize. The situation does not occur if the cpu-bound loop is on a different core than the core doing the IRETQ. The %rip the IRETQ returns to (e.g. userland %rip address) matters a *LOT*. The problem occurs more often with high %rip addresses such as near the top of the user stack, which is where DragonFly's signal trampoline traditionally resides. So a user program taking a signal on one thread while another thread is cpu-bound can cause this behavior. Changing the location of the signal trampoline makes it more difficult to reproduce the problem. I have not been because the able to completely mitigate it. When a cpu-thread stalls in this manner it appears to stall INSIDE the microcode for IRETQ. It doesn't make it to the return pc, and the cpu thread cannot take any IPIs or other hardware interrupts while in this state." since the system instability has been observed on FreeBSD with SMT disabled. Interrupts to appear to play a factor since running a signal-intensive process on the first CPU core, which handles most of the interrupts on my machine, is far more likely to trigger the problem than running such a process on any other core. Also lower sv_maxuser to prevent a malicious user from using mmap() to load and execute code in the top page of user memory that was made available when the shared page was moved down. Make the same changes to the 64-bit Linux emulator. PR: 219399 Reported by: nbe@renzel.net Reviewed by: kib Reviewed by: dchagin (previous version) Tested by: nbe@renzel.net (earlier version) MFC after: 2 weeks Differential Revision: https://reviews.freebsd.org/D11780
2017-08-02 01:43:35 +00:00
void amd64_lower_shared_page(struct sysentvec *);
void amd64_bsp_pcpu_init1(struct pcpu *pc);
void amd64_bsp_pcpu_init2(uint64_t rsp0);
void amd64_bsp_ist_init(struct pcpu *pc);
void amd64_syscall(struct thread *td, int traced);
void amd64_syscall_ret_flush_l1d(int error);
void amd64_syscall_ret_flush_l1d_recalc(void);
2002-03-20 05:48:58 +00:00
void doreti_iret(void) __asm(__STRING(doreti_iret));
void doreti_iret_fault(void) __asm(__STRING(doreti_iret_fault));
void flush_l1d_sw_abi(void);
void ld_ds(void) __asm(__STRING(ld_ds));
void ld_es(void) __asm(__STRING(ld_es));
void ld_fs(void) __asm(__STRING(ld_fs));
void ld_gs(void) __asm(__STRING(ld_gs));
void ld_fsbase(void) __asm(__STRING(ld_fsbase));
void ld_gsbase(void) __asm(__STRING(ld_gsbase));
void ds_load_fault(void) __asm(__STRING(ds_load_fault));
void es_load_fault(void) __asm(__STRING(es_load_fault));
void fs_load_fault(void) __asm(__STRING(fs_load_fault));
void gs_load_fault(void) __asm(__STRING(gs_load_fault));
void fsbase_load_fault(void) __asm(__STRING(fsbase_load_fault));
void gsbase_load_fault(void) __asm(__STRING(gsbase_load_fault));
void fpstate_drop(struct thread *td);
void pagezero(void *addr);
void setidt(int idx, alias_for_inthand_t *func, int typ, int dpl, int ist);
On amd64, declare sse2_pagezero() and start using it again, but only for zeroing pages in idle where nontemporal writes are clearly best. This is almost a no-op since zeroing in idle works does nothing good and is off by default. Fix END() statement forgotten in previous commit. Align the loop in sse2_pagezero(). Since it writes to main memory, the loop doesn't have to be very carefully written to keep up. Unrolling it was considered useless or harmful and was not done on i386, but that was too careless. Timing for i386: the loop was not unrolled at all, and moved only 4 bytes/iteration. So on a 2GHz CPU, it needed to run at 2 cycles/ iteration to keep up with a memory speed of just 4GB/sec. But when it crossed a 16-byte boundary, on old CPUs it ran at 3 cycles/ iteration so it gave a maximum speed of 2.67GB/sec and couldn't even keep up with PC3200 memory. Fix the alignment so that it keep up with 4GB/sec memory, and unroll once to get nearer to 8GB/sec. Further unrolling might be useless or harmful since it would prevent the loop fitting in 16-bytes. My test system with an old CPU and old DDR1 only needed 5+ GB/sec. My test system with a new CPU and DDR3 doesn't need any changes to keep up ~16GB/sec. Timing for amd64: with 8-byte accesses and newer faster CPUs it is easy to reach 16GB/sec but not so easy to go much faster. The alignment doesn't matter much if the CPU is not very old. The loop was already unrolled 4 times, but needs 32 bytes and uses a fancy method that doesn't work for 2-way unrolling in 16 bytes. Just align it to 32-bytes.
2016-08-29 13:07:21 +00:00
void sse2_pagezero(void *addr);
Add support for the extended FPU states on amd64, both for native 64bit and 32bit ABIs. As a side-effect, it enables AVX on capable CPUs. In particular: - Query the CPU support for XSAVE, list of the supported extensions and the required size of FPU save area. The hw.use_xsave tunable is provided for disabling XSAVE, and hw.xsave_mask may be used to select the enabled extensions. - Remove the FPU save area from PCB and dynamically allocate the (run-time sized) user save area on the top of the kernel stack, right above the PCB. Reorganize the thread0 PCB initialization to postpone it after BSP is queried for save area size. - The dumppcb, stoppcbs and susppcbs now do not carry the FPU state as well. FPU state is only useful for suspend, where it is saved in dynamically allocated suspfpusave area. - Use XSAVE and XRSTOR to save/restore FPU state, if supported and enabled. - Define new mcontext_t flag _MC_HASFPXSTATE, indicating that mcontext_t has a valid pointer to out-of-struct extended FPU state. Signal handlers are supplied with stack-allocated fpu state. The sigreturn(2) and setcontext(2) syscall honour the flag, allowing the signal handlers to inspect and manipilate extended state in the interrupted context. - The getcontext(2) never returns extended state, since there is no place in the fixed-sized mcontext_t to place variable-sized save area. And, since mcontext_t is embedded into ucontext_t, makes it impossible to fix in a reasonable way. Instead of extending getcontext(2) syscall, provide a sysarch(2) facility to query extended FPU state. - Add ptrace(2) support for getting and setting extended state; while there, implement missed PT_I386_{GET,SET}XMMREGS for 32bit binaries. - Change fpu_kern KPI to not expose struct fpu_kern_ctx layout to consumers, making it opaque. Internally, struct fpu_kern_ctx now contains a space for the extended state. Convert in-kernel consumers of fpu_kern KPI both on i386 and amd64. First version of the support for AVX was submitted by Tim Bird <tim.bird am sony com> on behalf of Sony. This version was written from scratch. Tested by: pho (previous version), Yamagi Burmeister <lists yamagi org> MFC after: 1 month
2012-01-21 17:45:27 +00:00
struct savefpu *get_pcb_user_save_td(struct thread *td);
struct savefpu *get_pcb_user_save_pcb(struct pcb *pcb);
Add pci_early function to detect Intel stolen memory. On some Intel devices BIOS does not properly reserve memory (called "stolen memory") for the GPU. If the stolen memory is claimed by the OS, functions that depend on stolen memory (like frame buffer compression) can't be used. A function called pci_early_quirks that is called before the virtual memory system is started was added. In Linux, this PCI early quirks function iterates through all PCI slots to check for any device that require quirks. While this more generic solution is preferable I only ported the Intel graphics specific parts because I think my implementation would be too similar to Linux GPL'd solution after looking at the Linux code too much. The code regarding Intel graphics stolen memory was ported from Linux. In the case of Intel graphics stolen memory this pci_early_quirks will read the stolen memory base and size from north bridge registers. The values are stored in global variables that is later read by linuxkpi_gplv2. Linuxkpi stores these values in a Linux-specific structure that is read by the drm driver. Relevant linuxkpi code is here: https://github.com/FreeBSDDesktop/kms-drm/blob/drm-v4.16/linuxkpi/gplv2/src/linux_compat.c#L37 For now, only amd64 arch is suppor ted since that is the only arch supported by the new drm drivers. I was told that Intel GPUs are always located on 0:2:0 so these values are hard coded for now. Note that the structure and early execution of the detection code is not required in its current form, but we expect that the code will be added shortly which fixes the potential BIOS bugs by reserving the stolen range in phys_avail[]. This must be done as early as possible to avoid conflicts with the potential usage of the memory in kernel. Submitted by: Johannes Lundberg <johalun0@gmail.com> Reviewed by: bwidawsk, imp MFC after: 1 week Differential revision: https://reviews.freebsd.org/D16719 Differential revision: https://reviews.freebsd.org/D17775
2018-10-31 23:17:00 +00:00
void pci_early_quirks(void);
#endif /* !_MACHINE_MD_VAR_H_ */