November 2023 - Linux-kselftest-mirror

[PATCH v12] exec: Fix dead-lock in de_thread with ptrace_attach

by Bernd Edlinger

This introduces signal->exec_bprm, which is used to fix the case when at least one of the sibling threads is traced, and therefore the trace process may dead-lock in ptrace_attach, but de_thread will need to wait for the tracer to continue execution. The solution is to detect this situation and allow ptrace_attach to continue by temporarily releasing the cred_guard_mutex, while de_thread() is still waiting for traced zombies to be eventually released by the tracer. In the case of the thread group leader we only have to wait for the thread to become a zombie, which may also need co-operation from the tracer due to PTRACE_O_TRACEEXIT. When a tracer wants to ptrace_attach a task that already is in execve, we simply retry the ptrace_may_access check while temporarily installing the new credentials and dumpability which are about to be used after execve completes. If the ptrace_attach happens on a thread that is a sibling-thread of the thread doing execve, it is sufficient to check against the old credentials, as this thread will be waited for, before the new credentials are installed. Other threads die quickly since the cred_guard_mutex is released, but a deadly signal is already pending. In case the mutex_lock_killable misses the signal, the non-zero current->signal->exec_bprm makes sure they release the mutex immediately and return with -ERESTARTNOINTR. This means there is no API change, unlike the previous version of this patch which was discussed here: https://lore.kernel.org/lkml/b6537ae6-31b1-5c50-f32b-8b8332ace882@hotmail.d… See tools/testing/selftests/ptrace/vmaccess.c for a test case that gets fixed by this change. Note that since the test case was originally designed to test the ptrace_attach returning an error in this situation, the test expectation needed to be adjusted, to allow the API to succeed at the first attempt. Signed-off-by: Bernd Edlinger <bernd.edlinger(a)hotmail.de> --- fs/exec.c | 69 ++++++++++++++++------- fs/proc/base.c | 6 ++ include/linux/cred.h | 1 + include/linux/sched/signal.h | 18 ++++++ kernel/cred.c | 28 +++++++-- kernel/ptrace.c | 32 +++++++++++ kernel/seccomp.c | 12 +++- tools/testing/selftests/ptrace/vmaccess.c | 23 +++++--- 8 files changed, 155 insertions(+), 34 deletions(-) v10: Changes to previous version, make the PTRACE_ATTACH retun -EAGAIN, instead of execve return -ERESTARTSYS. Added some lessions learned to the description. v11: Check old and new credentials in PTRACE_ATTACH again without changing the API. Note: I got actually one response from an automatic checker to the v11 patch, https://lore.kernel.org/lkml/202107121344.wu68hEPF-lkp@intel.com/ which is complaining about: >> kernel/ptrace.c:425:26: sparse: sparse: incorrect type in assignment (different address spaces) @@ expected struct cred const *old_cred @@ got struct cred const [noderef] __rcu *real_cred @@ 417 struct linux_binprm *bprm = task->signal->exec_bprm; 418 const struct cred *old_cred; 419 struct mm_struct *old_mm; 420 421 retval = down_write_killable(&task->signal->exec_update_lock); 422 if (retval) 423 goto unlock_creds; 424 task_lock(task); > 425 old_cred = task->real_cred; v12: Essentially identical to v11. - Fixed a minor merge conflict in linux v5.17, and fixed the above mentioned nit by adding __rcu to the declaration. - re-tested the patch with all linux versions from v5.11 to v6.6 v10 was an alternative approach which did imply an API change. But I would prefer to avoid such an API change. The difficult part is getting the right dumpability flags assigned before de_thread starts, hope you like this version. If not, the v10 is of course also acceptable. Thanks Bernd. diff --git a/fs/exec.c b/fs/exec.c index 2f2b0acec4f0..902d3b230485 100644 --- a/fs/exec.c +++ b/fs/exec.c @@ -1041,11 +1041,13 @@ static int exec_mmap(struct mm_struct *mm) return 0; } -static int de_thread(struct task_struct *tsk) +static int de_thread(struct task_struct *tsk, struct linux_binprm *bprm) { struct signal_struct *sig = tsk->signal; struct sighand_struct *oldsighand = tsk->sighand; spinlock_t *lock = &oldsighand->siglock; + struct task_struct *t = tsk; + bool unsafe_execve_in_progress = false; if (thread_group_empty(tsk)) goto no_thread_group; @@ -1068,6 +1070,19 @@ static int de_thread(struct task_struct *tsk) if (!thread_group_leader(tsk)) sig->notify_count--; + while_each_thread(tsk, t) { + if (unlikely(t->ptrace) + && (t != tsk->group_leader || !t->exit_state)) + unsafe_execve_in_progress = true; + } + + if (unlikely(unsafe_execve_in_progress)) { + spin_unlock_irq(lock); + sig->exec_bprm = bprm; + mutex_unlock(&sig->cred_guard_mutex); + spin_lock_irq(lock); + } + while (sig->notify_count) { __set_current_state(TASK_KILLABLE); spin_unlock_irq(lock); @@ -1158,6 +1173,11 @@ static int de_thread(struct task_struct *tsk) release_task(leader); } + if (unlikely(unsafe_execve_in_progress)) { + mutex_lock(&sig->cred_guard_mutex); + sig->exec_bprm = NULL; + } + sig->group_exec_task = NULL; sig->notify_count = 0; @@ -1169,6 +1189,11 @@ static int de_thread(struct task_struct *tsk) return 0; killed: + if (unlikely(unsafe_execve_in_progress)) { + mutex_lock(&sig->cred_guard_mutex); + sig->exec_bprm = NULL; + } + /* protects against exit_notify() and __exit_signal() */ read_lock(&tasklist_lock); sig->group_exec_task = NULL; @@ -1253,6 +1278,24 @@ int begin_new_exec(struct linux_binprm * bprm) if (retval) return retval; + /* If the binary is not readable then enforce mm->dumpable=0 */ + would_dump(bprm, bprm->file); + if (bprm->have_execfd) + would_dump(bprm, bprm->executable); + + /* + * Figure out dumpability. Note that this checking only of current + * is wrong, but userspace depends on it. This should be testing + * bprm->secureexec instead. + */ + if (bprm->interp_flags & BINPRM_FLAGS_ENFORCE_NONDUMP || + is_dumpability_changed(current_cred(), bprm->cred) || + !(uid_eq(current_euid(), current_uid()) && + gid_eq(current_egid(), current_gid()))) + set_dumpable(bprm->mm, suid_dumpable); + else + set_dumpable(bprm->mm, SUID_DUMP_USER); + /* * Ensure all future errors are fatal. */ @@ -1261,7 +1304,7 @@ int begin_new_exec(struct linux_binprm * bprm) /* * Make this the only thread in the thread group. */ - retval = de_thread(me); + retval = de_thread(me, bprm); if (retval) goto out; @@ -1284,11 +1327,6 @@ int begin_new_exec(struct linux_binprm * bprm) if (retval) goto out; - /* If the binary is not readable then enforce mm->dumpable=0 */ - would_dump(bprm, bprm->file); - if (bprm->have_execfd) - would_dump(bprm, bprm->executable); - /* * Release all of the old mmap stuff */ @@ -1350,18 +1388,6 @@ int begin_new_exec(struct linux_binprm * bprm) me->sas_ss_sp = me->sas_ss_size = 0; - /* - * Figure out dumpability. Note that this checking only of current - * is wrong, but userspace depends on it. This should be testing - * bprm->secureexec instead. - */ - if (bprm->interp_flags & BINPRM_FLAGS_ENFORCE_NONDUMP || - !(uid_eq(current_euid(), current_uid()) && - gid_eq(current_egid(), current_gid()))) - set_dumpable(current->mm, suid_dumpable); - else - set_dumpable(current->mm, SUID_DUMP_USER); - perf_event_exec(); __set_task_comm(me, kbasename(bprm->filename), true); @@ -1480,6 +1506,11 @@ static int prepare_bprm_creds(struct linux_binprm *bprm) if (mutex_lock_interruptible(&current->signal->cred_guard_mutex)) return -ERESTARTNOINTR; + if (unlikely(current->signal->exec_bprm)) { + mutex_unlock(&current->signal->cred_guard_mutex); + return -ERESTARTNOINTR; + } + bprm->cred = prepare_exec_creds(); if (likely(bprm->cred)) return 0; diff --git a/fs/proc/base.c b/fs/proc/base.c index ffd54617c354..0da9adfadb48 100644 --- a/fs/proc/base.c +++ b/fs/proc/base.c @@ -2788,6 +2788,12 @@ static ssize_t proc_pid_attr_write(struct file * file, const char __user * buf, if (rv < 0) goto out_free; + if (unlikely(current->signal->exec_bprm)) { + mutex_unlock(&current->signal->cred_guard_mutex); + rv = -ERESTARTNOINTR; + goto out_free; + } + rv = security_setprocattr(PROC_I(inode)->op.lsm, file->f_path.dentry->d_name.name, page, count); diff --git a/include/linux/cred.h b/include/linux/cred.h index f923528d5cc4..b01e309f5686 100644 --- a/include/linux/cred.h +++ b/include/linux/cred.h @@ -159,6 +159,7 @@ extern const struct cred *get_task_cred(struct task_struct *); extern struct cred *cred_alloc_blank(void); extern struct cred *prepare_creds(void); extern struct cred *prepare_exec_creds(void); +extern bool is_dumpability_changed(const struct cred *, const struct cred *); extern int commit_creds(struct cred *); extern void abort_creds(struct cred *); extern const struct cred *override_creds(const struct cred *); diff --git a/include/linux/sched/signal.h b/include/linux/sched/signal.h index 0014d3adaf84..14df7073a0a8 100644 --- a/include/linux/sched/signal.h +++ b/include/linux/sched/signal.h @@ -234,9 +234,27 @@ struct signal_struct { struct mm_struct *oom_mm; /* recorded mm when the thread group got * killed by the oom killer */ + struct linux_binprm *exec_bprm; /* Used to check ptrace_may_access + * against new credentials while + * de_thread is waiting for other + * traced threads to terminate. + * Set while de_thread is executing. + * The cred_guard_mutex is released + * after de_thread() has called + * zap_other_threads(), therefore + * a fatal signal is guaranteed to be + * already pending in the unlikely + * event, that + * current->signal->exec_bprm happens + * to be non-zero after the + * cred_guard_mutex was acquired. + */ + struct mutex cred_guard_mutex; /* guard against foreign influences on * credential calculations * (notably. ptrace) + * Held while execve runs, except when + * a sibling thread is being traced. * Deprecated do not use in new code. * Use exec_update_lock instead. */ diff --git a/kernel/cred.c b/kernel/cred.c index 98cb4eca23fb..586cb6c7cf6b 100644 --- a/kernel/cred.c +++ b/kernel/cred.c @@ -433,6 +433,28 @@ static bool cred_cap_issubset(const struct cred *set, const struct cred *subset) return false; } +/** + * is_dumpability_changed - Will changing creds from old to new + * affect the dumpability in commit_creds? + * + * Return: false - dumpability will not be changed in commit_creds. + * Return: true - dumpability will be changed to non-dumpable. + * + * @old: The old credentials + * @new: The new credentials + */ +bool is_dumpability_changed(const struct cred *old, const struct cred *new) +{ + if (!uid_eq(old->euid, new->euid) || + !gid_eq(old->egid, new->egid) || + !uid_eq(old->fsuid, new->fsuid) || + !gid_eq(old->fsgid, new->fsgid) || + !cred_cap_issubset(old, new)) + return true; + + return false; +} + /** * commit_creds - Install new credentials upon the current task * @new: The credentials to be assigned @@ -467,11 +489,7 @@ int commit_creds(struct cred *new) get_cred(new); /* we will require a ref for the subj creds too */ /* dumpability changes */ - if (!uid_eq(old->euid, new->euid) || - !gid_eq(old->egid, new->egid) || - !uid_eq(old->fsuid, new->fsuid) || - !gid_eq(old->fsgid, new->fsgid) || - !cred_cap_issubset(old, new)) { + if (is_dumpability_changed(old, new)) { if (task->mm) set_dumpable(task->mm, suid_dumpable); task->pdeath_signal = 0; diff --git a/kernel/ptrace.c b/kernel/ptrace.c index 443057bee87c..eb1c450bb7d7 100644 --- a/kernel/ptrace.c +++ b/kernel/ptrace.c @@ -20,6 +20,7 @@ #include <linux/pagemap.h> #include <linux/ptrace.h> #include <linux/security.h> +#include <linux/binfmts.h> #include <linux/signal.h> #include <linux/uio.h> #include <linux/audit.h> @@ -435,6 +436,28 @@ static int ptrace_attach(struct task_struct *task, long request, if (retval) goto unlock_creds; + if (unlikely(task->in_execve)) { + struct linux_binprm *bprm = task->signal->exec_bprm; + const struct cred __rcu *old_cred; + struct mm_struct *old_mm; + + retval = down_write_killable(&task->signal->exec_update_lock); + if (retval) + goto unlock_creds; + task_lock(task); + old_cred = task->real_cred; + old_mm = task->mm; + rcu_assign_pointer(task->real_cred, bprm->cred); + task->mm = bprm->mm; + retval = __ptrace_may_access(task, PTRACE_MODE_ATTACH_REALCREDS); + rcu_assign_pointer(task->real_cred, old_cred); + task->mm = old_mm; + task_unlock(task); + up_write(&task->signal->exec_update_lock); + if (retval) + goto unlock_creds; + } + write_lock_irq(&tasklist_lock); retval = -EPERM; if (unlikely(task->exit_state)) @@ -508,6 +531,14 @@ static int ptrace_traceme(void) { int ret = -EPERM; + if (mutex_lock_interruptible(&current->signal->cred_guard_mutex)) + return -ERESTARTNOINTR; + + if (unlikely(current->signal->exec_bprm)) { + mutex_unlock(&current->signal->cred_guard_mutex); + return -ERESTARTNOINTR; + } + write_lock_irq(&tasklist_lock); /* Are we already being traced? */ if (!current->ptrace) { @@ -523,6 +554,7 @@ static int ptrace_traceme(void) } } write_unlock_irq(&tasklist_lock); + mutex_unlock(&current->signal->cred_guard_mutex); return ret; } diff --git a/kernel/seccomp.c b/kernel/seccomp.c index 255999ba9190..b29bbfa0b044 100644 --- a/kernel/seccomp.c +++ b/kernel/seccomp.c @@ -1955,9 +1955,15 @@ static long seccomp_set_mode_filter(unsigned int flags, * Make sure we cannot change seccomp or nnp state via TSYNC * while another thread is in the middle of calling exec. */ - if (flags & SECCOMP_FILTER_FLAG_TSYNC && - mutex_lock_killable(&current->signal->cred_guard_mutex)) - goto out_put_fd; + if (flags & SECCOMP_FILTER_FLAG_TSYNC) { + if (mutex_lock_killable(&current->signal->cred_guard_mutex)) + goto out_put_fd; + + if (unlikely(current->signal->exec_bprm)) { + mutex_unlock(&current->signal->cred_guard_mutex); + goto out_put_fd; + } + } spin_lock_irq(&current->sighand->siglock); diff --git a/tools/testing/selftests/ptrace/vmaccess.c b/tools/testing/selftests/ptrace/vmaccess.c index 4db327b44586..3b7d81fb99bb 100644 --- a/tools/testing/selftests/ptrace/vmaccess.c +++ b/tools/testing/selftests/ptrace/vmaccess.c @@ -39,8 +39,15 @@ TEST(vmaccess) f = open(mm, O_RDONLY); ASSERT_GE(f, 0); close(f); - f = kill(pid, SIGCONT); - ASSERT_EQ(f, 0); + f = waitpid(-1, NULL, 0); + ASSERT_NE(f, -1); + ASSERT_NE(f, 0); + ASSERT_NE(f, pid); + f = waitpid(-1, NULL, 0); + ASSERT_EQ(f, pid); + f = waitpid(-1, NULL, 0); + ASSERT_EQ(f, -1); + ASSERT_EQ(errno, ECHILD); } TEST(attach) @@ -57,22 +64,24 @@ TEST(attach) sleep(1); k = ptrace(PTRACE_ATTACH, pid, 0L, 0L); - ASSERT_EQ(errno, EAGAIN); - ASSERT_EQ(k, -1); + ASSERT_EQ(k, 0); k = waitpid(-1, &s, WNOHANG); ASSERT_NE(k, -1); ASSERT_NE(k, 0); ASSERT_NE(k, pid); ASSERT_EQ(WIFEXITED(s), 1); ASSERT_EQ(WEXITSTATUS(s), 0); - sleep(1); - k = ptrace(PTRACE_ATTACH, pid, 0L, 0L); + k = waitpid(-1, &s, 0); + ASSERT_EQ(k, pid); + ASSERT_EQ(WIFSTOPPED(s), 1); + ASSERT_EQ(WSTOPSIG(s), SIGTRAP); + k = ptrace(PTRACE_CONT, pid, 0L, 0L); ASSERT_EQ(k, 0); k = waitpid(-1, &s, 0); ASSERT_EQ(k, pid); ASSERT_EQ(WIFSTOPPED(s), 1); ASSERT_EQ(WSTOPSIG(s), SIGSTOP); - k = ptrace(PTRACE_DETACH, pid, 0L, 0L); + k = ptrace(PTRACE_CONT, pid, 0L, 0L); ASSERT_EQ(k, 0); k = waitpid(-1, &s, 0); ASSERT_EQ(k, pid); -- 2.39.2

3 months, 2 weeks

5
14
0 0

[PATCH] selftests: core: include linux/close_range.h for CLOSE_RANGE_* macros

by Muhammad Usama Anjum

Correct header file is needed for getting CLOSE_RANGE_* macros. Previously it was tested with newer glibc which didn't show the need to include the header which was a mistake. Fixes: ec54424923cf ("selftests: core: remove duplicate defines") Reported-by: Aishwarya TCV <aishwarya.tcv(a)arm.com> Link: https://lore.kernel.org/all/7161219e-0223-d699-d6f3-81abd9abf13b@arm.com Signed-off-by: Muhammad Usama Anjum <usama.anjum(a)collabora.com> --- tools/testing/selftests/core/close_range_test.c | 1 + 1 file changed, 1 insertion(+) diff --git a/tools/testing/selftests/core/close_range_test.c b/tools/testing/selftests/core/close_range_test.c index 534576f06df1c..c59e4adb905df 100644 --- a/tools/testing/selftests/core/close_range_test.c +++ b/tools/testing/selftests/core/close_range_test.c @@ -12,6 +12,7 @@ #include <syscall.h> #include <unistd.h> #include <sys/resource.h> +#include <linux/close_range.h> #include "../kselftest_harness.h" #include "../clone3/clone3_selftests.h" -- 2.42.0

3 months, 2 weeks

1
4
0 0

[PATCH v10 0/4] RISC-V: mm: Make SV48 the default address space

by Charlie Jenkins

Make sv48 the default address space for mmap as some applications currently depend on this assumption. Users can now select a desired address space using a non-zero hint address to mmap. Previously, requesting the default address space from mmap by passing zero as the hint address would result in using the largest address space possible. Some applications depend on empty bits in the virtual address space, like Go and Java, so this patch provides more flexibility for application developers. -Charlie --- v10: - Move pgtable.h defintions into a no __ASSEMBLY__ region to resolve compilation conflicts (pointed out by Conor) - Will now compile with allmodconfig v9: - Raise the mmap_end default to STACK_TOP_MAX to allow the address space to grow beyond the default of sv48 on sv57 machines as suggested by Alexandre - Some of the mmap macros had unnecessary conditionals that I have removed v8: - Fix RV32 and the RV32 compat mode of RV64 (suggested by Conor) - Extract out addr and base from the mmap macros (suggested by Alexandre) v7: - Changing RLIMIT_STACK inside of an executing program does not trigger arch_pick_mmap_layout(), so rewrite tests to change RLIMIT_STACK from a script before executing tests. RLIMIT_STACK of infinity forces bottomup mmap allocation. - Make arch_get_mmap_base macro more readible by extracting out the rnd calculation. - Use MMAP_MIN_VA_BITS in TASK_UNMAPPED_BASE to support case when mmap attempts to allocate address smaller than DEFAULT_MAP_WINDOW. - Fix incorrect wording in documentation. v6: - Rebase onto the correct base v5: - Minor wording change in documentation - Change some parenthesis in arch_get_mmap_ macros - Added case for addr==0 in arch_get_mmap_ because without this, programs would crash if RLIMIT_STACK was modified before executing the program. This was tested using the libhugetlbfs tests. v4: - Split testcases/document patch into test cases, in-code documentation, and formal documentation patches - Modified the mmap_base macro to be more legible and better represent memory layout - Fixed documentation to better reflect the implmentation - Renamed DEFAULT_VA_BITS to MMAP_VA_BITS - Added additional test case for rlimit changes --- Charlie Jenkins (4): RISC-V: mm: Restrict address space for sv39,sv48,sv57 RISC-V: mm: Add tests for RISC-V mm RISC-V: mm: Update pgtable comment documentation RISC-V: mm: Document mmap changes Documentation/riscv/vm-layout.rst | 22 +++++++ arch/riscv/include/asm/elf.h | 2 +- arch/riscv/include/asm/pgtable.h | 33 ++++++++-- arch/riscv/include/asm/processor.h | 52 +++++++++++++-- tools/testing/selftests/riscv/Makefile | 2 +- tools/testing/selftests/riscv/mm/.gitignore | 2 + tools/testing/selftests/riscv/mm/Makefile | 15 +++++ .../riscv/mm/testcases/mmap_bottomup.c | 35 ++++++++++ .../riscv/mm/testcases/mmap_default.c | 35 ++++++++++ .../selftests/riscv/mm/testcases/mmap_test.h | 64 +++++++++++++++++++ .../selftests/riscv/mm/testcases/run_mmap.sh | 12 ++++ 11 files changed, 261 insertions(+), 13 deletions(-) create mode 100644 tools/testing/selftests/riscv/mm/.gitignore create mode 100644 tools/testing/selftests/riscv/mm/Makefile create mode 100644 tools/testing/selftests/riscv/mm/testcases/mmap_bottomup.c create mode 100644 tools/testing/selftests/riscv/mm/testcases/mmap_default.c create mode 100644 tools/testing/selftests/riscv/mm/testcases/mmap_test.h create mode 100755 tools/testing/selftests/riscv/mm/testcases/run_mmap.sh -- 2.34.1

3 months, 2 weeks

3
11
0 0

[PATCH v7 00/39] arm64/gcs: Provide support for GCS in userspace

by Mark Brown

The arm64 Guarded Control Stack (GCS) feature provides support for hardware protected stacks of return addresses, intended to provide hardening against return oriented programming (ROP) attacks and to make it easier to gather call stacks for applications such as profiling. When GCS is active a secondary stack called the Guarded Control Stack is maintained, protected with a memory attribute which means that it can only be written with specific GCS operations. The current GCS pointer can not be directly written to by userspace. When a BL is executed the value stored in LR is also pushed onto the GCS, and when a RET is executed the top of the GCS is popped and compared to LR with a fault being raised if the values do not match. GCS operations may only be performed on GCS pages, a data abort is generated if they are not. The combination of hardware enforcement and lack of extra instructions in the function entry and exit paths should result in something which has less overhead and is more difficult to attack than a purely software implementation like clang's shadow stacks. This series implements support for use of GCS by userspace, along with support for use of GCS within KVM guests. It does not enable use of GCS by either EL1 or EL2, this will be implemented separately. Executables are started without GCS and must use a prctl() to enable it, it is expected that this will be done very early in application execution by the dynamic linker or other startup code. For dynamic linking this will be done by checking that everything in the executable is marked as GCS compatible. x86 has an equivalent feature called shadow stacks, this series depends on the x86 patches for generic memory management support for the new guarded/shadow stack page type and shares APIs as much as possible. As there has been extensive discussion with the wider community around the ABI for shadow stacks I have as far as practical kept implementation decisions close to those for x86, anticipating that review would lead to similar conclusions in the absence of strong reasoning for divergence. The main divergence I am concious of is that x86 allows shadow stack to be enabled and disabled repeatedly, freeing the shadow stack for the thread whenever disabled, while this implementation keeps the GCS allocated after disable but refuses to reenable it. This is to avoid races with things actively walking the GCS during a disable, we do anticipate that some systems will wish to disable GCS at runtime but are not aware of any demand for subsequently reenabling it. x86 uses an arch_prctl() to manage enable and disable, since only x86 and S/390 use arch_prctl() a generic prctl() was proposed[1] as part of a patch set for the equivalent RISC-V Zicfiss feature which I initially adopted fairly directly but following review feedback has been revised quite a bit. We currently maintain the x86 pattern of implicitly allocating a shadow stack for threads started with shadow stack enabled, there has been some discussion of removing this support and requiring the use of clone3() with explicit allocation of shadow stacks instead. I have no strong feelings either way, implicit allocation is not really consistent with anything else we do and creates the potential for errors around thread exit but on the other hand it is existing ABI on x86 and minimises the changes needed in userspace code. There is an open issue with support for CRIU, on x86 this required the ability to set the GCS mode via ptrace. This series supports configuring mode bits other than enable/disable via ptrace but it needs to be confirmed if this is sufficient. The series depends on support for shadow stacks in clone3(), that series includes the addition of ARCH_HAS_USER_SHADOW_STACK. https://lore.kernel.org/r/20231120-clone3-shadow-stack-v3-0-a7b8ed3e2acc@ke… It also depends on the addition of more waitpid() flags to nolibc: https://lore.kernel.org/r/20231023-nolibc-waitpid-flags-v2-1-b09d096f091f@k… You can see a branch with the full set of dependencies against Linus' tree at: https://git.kernel.org/pub/scm/linux/kernel/git/broonie/misc.git arm64-gcs [1] https://lore.kernel.org/lkml/20230213045351.3945824-1-debug@rivosinc.com/ Signed-off-by: Mark Brown <broonie(a)kernel.org> --- Changes in v7: - Rebase onto v6.7-rc2 via the clone3() patch series. - Change the token used to cap the stack during signal handling to be compatible with GCSPOPM. - Fix flags for new page types. - Fold in support for clone3(). - Replace copy_to_user_gcs() with put_user_gcs(). - Link to v6: https://lore.kernel.org/r/20231009-arm64-gcs-v6-0-78e55deaa4dd@kernel.org Changes in v6: - Rebase onto v6.6-rc3. - Add some more gcsb_dsync() barriers following spec clarifications. - Due to ongoing discussion around clone()/clone3() I've not updated anything there, the behaviour is the same as on previous versions. - Link to v5: https://lore.kernel.org/r/20230822-arm64-gcs-v5-0-9ef181dd6324@kernel.org Changes in v5: - Don't map any permissions for user GCSs, we always use EL0 accessors or use a separate mapping of the page. - Reduce the standard size of the GCS to RLIMIT_STACK/2. - Enforce a PAGE_SIZE alignment requirement on map_shadow_stack(). - Clarifications and fixes to documentation. - More tests. - Link to v4: https://lore.kernel.org/r/20230807-arm64-gcs-v4-0-68cfa37f9069@kernel.org Changes in v4: - Implement flags for map_shadow_stack() allowing the cap and end of stack marker to be enabled independently or not at all. - Relax size and alignment requirements for map_shadow_stack(). - Add more blurb explaining the advantages of hardware enforcement. - Link to v3: https://lore.kernel.org/r/20230731-arm64-gcs-v3-0-cddf9f980d98@kernel.org Changes in v3: - Rebase onto v6.5-rc4. - Add a GCS barrier on context switch. - Add a GCS stress test. - Link to v2: https://lore.kernel.org/r/20230724-arm64-gcs-v2-0-dc2c1d44c2eb@kernel.org Changes in v2: - Rebase onto v6.5-rc3. - Rework prctl() interface to allow each bit to be locked independently. - map_shadow_stack() now places the cap token based on the size requested by the caller not the actual space allocated. - Mode changes other than enable via ptrace are now supported. - Expand test coverage. - Various smaller fixes and adjustments. - Link to v1: https://lore.kernel.org/r/20230716-arm64-gcs-v1-0-bf567f93bba6@kernel.org --- Mark Brown (39): arm64/mm: Restructure arch_validate_flags() for extensibility prctl: arch-agnostic prctl for shadow stack mman: Add map_shadow_stack() flags arm64: Document boot requirements for Guarded Control Stacks arm64/gcs: Document the ABI for Guarded Control Stacks arm64/sysreg: Add new system registers for GCS arm64/sysreg: Add definitions for architected GCS caps arm64/gcs: Add manual encodings of GCS instructions arm64/gcs: Provide put_user_gcs() arm64/cpufeature: Runtime detection of Guarded Control Stack (GCS) arm64/mm: Allocate PIE slots for EL0 guarded control stack mm: Define VM_SHADOW_STACK for arm64 when we support GCS arm64/mm: Map pages for guarded control stack KVM: arm64: Manage GCS registers for guests arm64/gcs: Allow GCS usage at EL0 and EL1 arm64/idreg: Add overrride for GCS arm64/hwcap: Add hwcap for GCS arm64/traps: Handle GCS exceptions arm64/mm: Handle GCS data aborts arm64/gcs: Context switch GCS state for EL0 arm64/gcs: Allocate a new GCS for threads with GCS enabled arm64/gcs: Implement shadow stack prctl() interface arm64/mm: Implement map_shadow_stack() arm64/signal: Set up and restore the GCS context for signal handlers arm64/signal: Expose GCS state in signal frames arm64/ptrace: Expose GCS via ptrace and core files arm64: Add Kconfig for Guarded Control Stack (GCS) kselftest/arm64: Verify the GCS hwcap kselftest/arm64: Add GCS as a detected feature in the signal tests kselftest/arm64: Add framework support for GCS to signal handling tests kselftest/arm64: Allow signals tests to specify an expected si_code kselftest/arm64: Always run signals tests with GCS enabled kselftest/arm64: Add very basic GCS test program kselftest/arm64: Add a GCS test program built with the system libc kselftest/arm64: Add test coverage for GCS mode locking selftests/arm64: Add GCS signal tests kselftest/arm64: Add a GCS stress test kselftest/arm64: Enable GCS for the FP stress tests kselftest/clone3: Enable GCS in the clone3 selftests Documentation/admin-guide/kernel-parameters.txt | 6 + Documentation/arch/arm64/booting.rst | 22 + Documentation/arch/arm64/elf_hwcaps.rst | 3 + Documentation/arch/arm64/gcs.rst | 233 +++++++ Documentation/arch/arm64/index.rst | 1 + Documentation/filesystems/proc.rst | 2 +- arch/arm64/Kconfig | 20 + arch/arm64/include/asm/cpufeature.h | 6 + arch/arm64/include/asm/el2_setup.h | 17 + arch/arm64/include/asm/esr.h | 28 +- arch/arm64/include/asm/exception.h | 2 + arch/arm64/include/asm/gcs.h | 107 +++ arch/arm64/include/asm/hwcap.h | 1 + arch/arm64/include/asm/kvm_arm.h | 4 +- arch/arm64/include/asm/kvm_host.h | 12 + arch/arm64/include/asm/mman.h | 23 +- arch/arm64/include/asm/pgtable-prot.h | 14 +- arch/arm64/include/asm/processor.h | 7 + arch/arm64/include/asm/sysreg.h | 20 + arch/arm64/include/asm/uaccess.h | 40 ++ arch/arm64/include/uapi/asm/hwcap.h | 1 + arch/arm64/include/uapi/asm/ptrace.h | 8 + arch/arm64/include/uapi/asm/sigcontext.h | 9 + arch/arm64/kernel/cpufeature.c | 19 + arch/arm64/kernel/cpuinfo.c | 1 + arch/arm64/kernel/entry-common.c | 23 + arch/arm64/kernel/idreg-override.c | 2 + arch/arm64/kernel/process.c | 81 +++ arch/arm64/kernel/ptrace.c | 59 ++ arch/arm64/kernel/signal.c | 236 ++++++- arch/arm64/kernel/traps.c | 11 + arch/arm64/kvm/hyp/include/hyp/sysreg-sr.h | 17 + arch/arm64/kvm/sys_regs.c | 22 + arch/arm64/mm/Makefile | 1 + arch/arm64/mm/fault.c | 79 ++- arch/arm64/mm/gcs.c | 259 +++++++ arch/arm64/mm/mmap.c | 13 +- arch/arm64/tools/cpucaps | 1 + arch/arm64/tools/sysreg | 55 ++ arch/x86/include/uapi/asm/mman.h | 3 - fs/proc/task_mmu.c | 3 + include/linux/mm.h | 16 +- include/uapi/asm-generic/mman.h | 4 + include/uapi/linux/elf.h | 1 + include/uapi/linux/prctl.h | 22 + kernel/sys.c | 30 + tools/testing/selftests/arm64/Makefile | 2 +- tools/testing/selftests/arm64/abi/hwcap.c | 19 + tools/testing/selftests/arm64/fp/assembler.h | 15 + tools/testing/selftests/arm64/fp/fpsimd-test.S | 2 + tools/testing/selftests/arm64/fp/sve-test.S | 2 + tools/testing/selftests/arm64/fp/za-test.S | 2 + tools/testing/selftests/arm64/fp/zt-test.S | 2 + tools/testing/selftests/arm64/gcs/.gitignore | 5 + tools/testing/selftests/arm64/gcs/Makefile | 24 + tools/testing/selftests/arm64/gcs/asm-offsets.h | 0 tools/testing/selftests/arm64/gcs/basic-gcs.c | 428 ++++++++++++ tools/testing/selftests/arm64/gcs/gcs-locking.c | 200 ++++++ .../selftests/arm64/gcs/gcs-stress-thread.S | 311 +++++++++ tools/testing/selftests/arm64/gcs/gcs-stress.c | 532 +++++++++++++++ tools/testing/selftests/arm64/gcs/gcs-util.h | 100 +++ tools/testing/selftests/arm64/gcs/libc-gcs.c | 742 +++++++++++++++++++++ tools/testing/selftests/arm64/signal/.gitignore | 1 + .../testing/selftests/arm64/signal/test_signals.c | 17 +- .../testing/selftests/arm64/signal/test_signals.h | 6 + .../selftests/arm64/signal/test_signals_utils.c | 32 +- .../selftests/arm64/signal/test_signals_utils.h | 39 ++ .../arm64/signal/testcases/gcs_exception_fault.c | 59 ++ .../selftests/arm64/signal/testcases/gcs_frame.c | 78 +++ .../arm64/signal/testcases/gcs_write_fault.c | 67 ++ .../selftests/arm64/signal/testcases/testcases.c | 7 + .../selftests/arm64/signal/testcases/testcases.h | 1 + tools/testing/selftests/clone3/clone3.c | 37 + 73 files changed, 4234 insertions(+), 40 deletions(-) --- base-commit: 3d0134d322380292c055454d9633738733992d61 change-id: 20230303-arm64-gcs-e311ab0d8729 Best regards, -- Mark Brown <broonie(a)kernel.org>

3 months, 3 weeks

4
68
0 0

[PATCH 00/15] KVM RISC-V report more ISA extensions through ONE_REG

by Anup Patel

This extends the KVM RISC-V ONE_REG interface to report more ISA extensions namely: Zbz, scalar crypto, vector crypto, Zfh[min], Zihintntl, Zvfh[min], and Zfa. This series depends upon the "riscv: report more ISA extensions through hwprobe" series.from Clement. (Link: https://lore.kernel.org/lkml/20231114141256.126749-1-cleger@rivosinc.com/) To test these patches, use KVMTOOL from the riscv_more_exts_v1 branch at: https://github.com/avpatel/kvmtool.git These patches can also be found in the riscv_kvm_more_exts_v1 branch at: https://github.com/avpatel/linux.git Anup Patel (15): KVM: riscv: selftests: Generate ISA extension reg_list using macros RISC-V: KVM: Allow Zbc extension for Guest/VM KVM: riscv: selftests: Add Zbc extension to get-reg-list test RISC-V: KVM: Allow scalar crypto extensions for Guest/VM KVM: riscv: selftests: Add scaler crypto extensions to get-reg-list test RISC-V: KVM: Allow vector crypto extensions for Guest/VM KVM: riscv: selftests: Add vector crypto extensions to get-reg-list test RISC-V: KVM: Allow Zfh[min] extensions for Guest/VM KVM: riscv: selftests: Add Zfh[min] extensions to get-reg-list test RISC-V: KVM: Allow Zihintntl extension for Guest/VM KVM: riscv: selftests: Add Zihintntl extension to get-reg-list test RISC-V: KVM: Allow Zvfh[min] extensions for Guest/VM KVM: riscv: selftests: Add Zvfh[min] extensions to get-reg-list test RISC-V: KVM: Allow Zfa extension for Guest/VM KVM: riscv: selftests: Add Zfa extension to get-reg-list test arch/riscv/include/uapi/asm/kvm.h | 27 ++ arch/riscv/kvm/vcpu_onereg.c | 54 +++ .../selftests/kvm/riscv/get-reg-list.c | 439 ++++++++---------- 3 files changed, 265 insertions(+), 255 deletions(-) -- 2.34.1

3 months, 3 weeks

3
32
0 0

[PATCH v2 0/6] IOMMUFD: Deliver IO page faults to user space

by Lu Baolu

Hi folks, This series implements the functionality of delivering IO page faults to user space through the IOMMUFD framework for nested translation. Nested translation is a hardware feature that supports two-stage translation tables for IOMMU. The second-stage translation table is managed by the host VMM, while the first-stage translation table is owned by user space. This allows user space to control the IOMMU mappings for its devices. When an IO page fault occurs on the first-stage translation table, the IOMMU hardware can deliver the page fault to user space through the IOMMUFD framework. User space can then handle the page fault and respond to the device top-down through the IOMMUFD. This allows user space to implement its own IO page fault handling policies. User space indicates its capability of handling IO page faults by setting the IOMMU_HWPT_ALLOC_IOPF_CAPABLE flag when allocating a hardware page table (HWPT). IOMMUFD will then set up its infrastructure for page fault delivery. On a successful return of HWPT allocation, the user can retrieve and respond to page faults by reading and writing to the file descriptor (FD) returned in out_fault_fd. The iommu selftest framework has been updated to test the IO page fault delivery and response functionality. This series is based on the latest implementation of nested translation under discussion [1] and the page fault handling framework refactoring in the IOMMU core [2]. The series and related patches are available on GitHub: [3] [1] https://lore.kernel.org/linux-iommu/20230921075138.124099-1-yi.l.liu@intel.… [2] https://lore.kernel.org/linux-iommu/20230928042734.16134-1-baolu.lu@linux.i… [3] https://github.com/LuBaolu/intel-iommu/commits/iommufd-io-pgfault-delivery-… Best regards, baolu Change log: v2: - Move all iommu refactoring patches into a sparated series and discuss it in a different thread. The latest patch series [v6] is available at https://lore.kernel.org/linux-iommu/20230928042734.16134-1-baolu.lu@linux.i… - We discussed the timeout of the pending page fault messages. We agreed that we shouldn't apply any timeout policy for the page fault handling in user space. https://lore.kernel.org/linux-iommu/20230616113232.GA84678@myrica/ - Jason suggested that we adopt a simple file descriptor interface for reading and responding to I/O page requests, so that user space applications can improve performance using io_uring. https://lore.kernel.org/linux-iommu/ZJWjD1ajeem6pK3I@ziepe.ca/ v1: https://lore.kernel.org/linux-iommu/20230530053724.232765-1-baolu.lu@linux.… Lu Baolu (6): iommu: Add iommu page fault cookie helpers iommufd: Add iommu page fault uapi data iommufd: Initializing and releasing IO page fault data iommufd: Deliver fault messages to user space iommufd/selftest: Add IOMMU_TEST_OP_TRIGGER_IOPF test support iommufd/selftest: Add coverage for IOMMU_TEST_OP_TRIGGER_IOPF include/linux/iommu.h | 9 + drivers/iommu/iommu-priv.h | 15 + drivers/iommu/iommufd/iommufd_private.h | 12 + drivers/iommu/iommufd/iommufd_test.h | 8 + include/uapi/linux/iommufd.h | 65 +++++ tools/testing/selftests/iommu/iommufd_utils.h | 66 ++++- drivers/iommu/io-pgfault.c | 50 ++++ drivers/iommu/iommufd/device.c | 69 ++++- drivers/iommu/iommufd/hw_pagetable.c | 260 +++++++++++++++++- drivers/iommu/iommufd/selftest.c | 56 ++++ tools/testing/selftests/iommu/iommufd.c | 24 +- .../selftests/iommu/iommufd_fail_nth.c | 2 +- 12 files changed, 620 insertions(+), 16 deletions(-) -- 2.34.1

3 months, 3 weeks

6
42
0 0

[PATCH 0/3] vfio-pci support pasid attach/detach

by Yi Liu

This adds the pasid attach/detach uAPIs for userspace to attach/detach a PASID of a device to/from a given ioas/hwpt. Only vfio-pci driver is enabled in this series. After this series, PASID-capable devices bound with vfio-pci can report PASID capability to userspace and VM to enable PASID usages like Shared Virtual Addressing (SVA). This series first adds the helpers for pasid attach in vfio core and then add the device cdev ioctls for pasid attach/detach, finally exposes the device PASID capability to user. It depends on iommufd pasid attach/detach series [1]. Complete code can be found at [2], tested with a draft Qemu branch[3] [1] https://lore.kernel.org/linux-iommu/20231127063428.127436-1-yi.l.liu@intel.… [2] https://github.com/yiliu1765/iommufd/tree/iommufd_pasid [3] https://github.com/yiliu1765/qemu/tree/zhenzhong/wip/iommufd_nesting_rfcv1%… Change log: v1: - Report PASID capability via VFIO_DEVICE_FEATURE (Alex) rfc: https://lore.kernel.org/linux-iommu/20230926093121.18676-1-yi.l.liu@intel.c… Regards, Yi Liu Kevin Tian (1): vfio-iommufd: Support pasid [at|de]tach for physical VFIO devices Yi Liu (2): vfio: Add VFIO_DEVICE_PASID_[AT|DE]TACH_IOMMUFD_PT vfio: Report PASID capability via VFIO_DEVICE_FEATURE ioctl drivers/vfio/device_cdev.c | 45 +++++++++++++++++++++ drivers/vfio/iommufd.c | 48 ++++++++++++++++++++++ drivers/vfio/pci/vfio_pci.c | 2 + drivers/vfio/pci/vfio_pci_core.c | 47 ++++++++++++++++++++++ drivers/vfio/vfio.h | 4 ++ drivers/vfio/vfio_main.c | 8 ++++ include/linux/vfio.h | 11 ++++++ include/uapi/linux/vfio.h | 68 ++++++++++++++++++++++++++++++++ 8 files changed, 233 insertions(+) -- 2.34.1

3 months, 3 weeks

5
30
0 0

[PATCH 0/5] tools: selftests: riscv: Fix compiler warnings

by Christoph Muellner

From: Christoph Müllner <christoph.muellner(a)vrull.eu> When building the RISC-V selftests with a riscv32 compiler I ran into a couple of compiler warnings. While riscv32 support for these tests is questionable, the fixes are so trivial that it is probably best to simply apply them. Note that the missing-include patch and some format string warnings are also relevant for riscv64. Christoph Müllner (5): tools: selftests: riscv: Fix compile warnings in hwprobe tools: selftests: riscv: Fix compile warnings in cbo tools: selftests: riscv: Add missing include for vector test tools: selftests: riscv: Fix compile warnings in vector tests tools: selftests: riscv: Fix compile warnings in mm tests tools/testing/selftests/riscv/hwprobe/cbo.c | 6 +++--- tools/testing/selftests/riscv/hwprobe/hwprobe.c | 4 ++-- tools/testing/selftests/riscv/mm/mmap_test.h | 3 +++ tools/testing/selftests/riscv/vector/v_initval_nolibc.c | 2 +- tools/testing/selftests/riscv/vector/vstate_exec_nolibc.c | 3 +++ tools/testing/selftests/riscv/vector/vstate_prctl.c | 4 ++-- 6 files changed, 14 insertions(+), 8 deletions(-) -- 2.41.0

3 months, 3 weeks

6
15
0 0

[PATCH v7 0/3] Add Intel VT-d nested translation (part 2/2)

by Yi Liu

This is the second part to add Intel VT-d nested translation based on IOMMUFD nesting infrastructure. As the iommufd nesting infrastructure series [1], iommu core supports new ops to invalidate the cache after the modifictions in stage-1 page table. So far, the cache invalidation data is vendor specific, the data_type (IOMMU_HWPT_DATA_VTD_S1) defined for the vendor specific HWPT allocation is reused in the cache invalidation path. User should provide the correct data_type that suit with the type used in HWPT allocation. IOMMU_HWPT_INVALIDATE iotcl returns an error in @out_driver_error_code. However Intel VT-d does not define error code so far, so it's not easy to pre-define it in iommufd neither. As a result, this field should just be ignored on VT-d platform. Complete code can be found in [2], corresponding QEMU could can be found in [3]. [1] https://lore.kernel.org/linux-iommu/20231117130717.19875-1-yi.l.liu@intel.c… [2] https://github.com/yiliu1765/iommufd/tree/iommufd_nesting [3] https://github.com/yiliu1765/qemu/tree/zhenzhong/wip/iommufd_nesting_rfcv1 Change log: v7: - No much change, just rebase on top of 6.7-rc1 v6: https://lore.kernel.org/linux-iommu/20231020093719.18725-1-yi.l.liu@intel.c… - Address comments from Kevin - Split the VT-d nesting series into two parts (Jason) v5: https://lore.kernel.org/linux-iommu/20230921075431.125239-1-yi.l.liu@intel.… - Add Kevin's r-b for patch 2, 3 ,5 8, 10 - Drop enforce_cache_coherency callback from the nested type domain ops (Kevin) - Remove duplicate agaw check in patch 04 (Kevin) - Remove duplicate domain_update_iommu_cap() in patch 06 (Kevin) - Check parent's force_snooping to set pgsnp in the pasid entry (Kevin) - uapi data structure check (Kevin) - Simplify the errata handling as user can allocate nested parent domain v4: https://lore.kernel.org/linux-iommu/20230724111335.107427-1-yi.l.liu@intel.… - Remove ascii art tables (Jason) - Drop EMT (Tina, Jason) - Drop MTS and related definitions (Kevin) - Rename macro IOMMU_VTD_PGTBL_ to IOMMU_VTD_S1_ (Kevin) - Rename struct iommu_hwpt_intel_vtd_ to iommu_hwpt_vtd_ (Kevin) - Rename struct iommu_hwpt_intel_vtd to iommu_hwpt_vtd_s1 (Kevin) - Put the vendor specific hwpt alloc data structure before enuma iommu_hwpt_type (Kevin) - Do not trim the higher page levels of S2 domain in nested domain attachment as the S2 domain may have been used independently. (Kevin) - Remove the first-stage pgd check against the maximum address of s2_domain as hw can check it anyhow. It makes sense to check every pfns used in the stage-1 page table. But it cannot make it. So just leave it to hw. (Kevin) - Split the iotlb flush part into an order of uapi, helper and callback implementation (Kevin) - Change the policy of VT-d nesting errata, disallow RO mapping once a domain is used as parent domain of a nested domain. This removes the nested_users counting. (Kevin) - Minor fix for "make htmldocs" v3: https://lore.kernel.org/linux-iommu/20230511145110.27707-1-yi.l.liu@intel.c… - Further split the patches into an order of adding helpers for nested domain, iotlb flush, nested domain attachment and nested domain allocation callback, then report the hw_info to userspace. - Add batch support in cache invalidation from userspace - Disallow nested translation usage if RO mappings exists in stage-2 domain due to errata on readonly mappings on Sapphire Rapids platform. v2: https://lore.kernel.org/linux-iommu/20230309082207.612346-1-yi.l.liu@intel.… - The iommufd infrastructure is split to be separate series. v1: https://lore.kernel.org/linux-iommu/20230209043153.14964-1-yi.l.liu@intel.c… Regards, Yi Liu Yi Liu (3): iommufd: Add data structure for Intel VT-d stage-1 cache invalidation iommu/vt-d: Make iotlb flush helpers to be extern iommu/vt-d: Add iotlb flush for nested domain drivers/iommu/intel/iommu.c | 10 +++---- drivers/iommu/intel/iommu.h | 6 ++++ drivers/iommu/intel/nested.c | 54 ++++++++++++++++++++++++++++++++++++ include/uapi/linux/iommufd.h | 36 ++++++++++++++++++++++++ 4 files changed, 101 insertions(+), 5 deletions(-) -- 2.34.1

4 months

5
44
0 0

[PATCH v6 0/6] iommufd: Add nesting infrastructure (part 2/2)

by Yi Liu

Nested translation is a hardware feature that is supported by many modern IOMMU hardwares. It has two stages (stage-1, stage-2) address translation to get access to the physical address. stage-1 translation table is owned by userspace (e.g. by a guest OS), while stage-2 is owned by kernel. Changes to stage-1 translation table should be followed by an IOTLB invalidation. Take Intel VT-d as an example, the stage-1 translation table is I/O page table. As the below diagram shows, guest I/O page table pointer in GPA (guest physical address) is passed to host and be used to perform the stage-1 address translation. Along with it, modifications to present mappings in the guest I/O page table should be followed with an IOTLB invalidation. .-------------. .---------------------------. | vIOMMU | | Guest I/O page table | | | '---------------------------' .----------------/ | PASID Entry |--- PASID cache flush --+ '-------------' | | | V | | I/O page table pointer in GPA '-------------' Guest ------| Shadow |---------------------------|-------- v v v Host .-------------. .------------------------. | pIOMMU | | FS for GIOVA->GPA | | | '------------------------' .----------------/ | | PASID Entry | V (Nested xlate) '----------------\.----------------------------------. | | | SS for GPA->HPA, unmanaged domain| | | '----------------------------------' '-------------' Where: - FS = First stage page tables - SS = Second stage page tables <Intel VT-d Nested translation> This series adds the cache invalidation path for the userspace to invalidate cache after modifying the stage-1 page table. This is based on the first part of nesting [1] Complete code can be found in [2], QEMU could can be found in [3]. At last, this is a team work together with Nicolin Chen, Lu Baolu. Thanks them for the help. ^_^. Look forward to your feedbacks. [1] https://lore.kernel.org/linux-iommu/20231026044216.64964-1-yi.l.liu@intel.c… - merged [2] https://github.com/yiliu1765/iommufd/tree/iommufd_nesting [3] https://github.com/yiliu1765/qemu/tree/zhenzhong/wip/iommufd_nesting_rfcv1 Change log: v6: - No much change, just rebase on top of 6.7-rc1 as part 1/2 is merged v5: https://lore.kernel.org/linux-iommu/20231020092426.13907-1-yi.l.liu@intel.c… - Split the iommufd nesting series into two parts of alloc_user and invalidation (Jason) - Split IOMMUFD_OBJ_HW_PAGETABLE to IOMMUFD_OBJ_HWPT_PAGING/_NESTED, and do the same with the structures/alloc()/abort()/destroy(). Reworked the selftest accordingly too. (Jason) - Move hwpt/data_type into struct iommu_user_data from standalone op arguments. (Jason) - Rename hwpt_type to be data_type, the HWPT_TYPE to be HWPT_ALLOC_DATA, _TYPE_DEFAULT to be _ALLOC_DATA_NONE (Jason, Kevin) - Rename iommu_copy_user_data() to iommu_copy_struct_from_user() (Kevin) - Add macro to the iommu_copy_struct_from_user() to calculate min_size (Jason) - Fix two bugs spotted by ZhaoYan v4: https://lore.kernel.org/linux-iommu/20230921075138.124099-1-yi.l.liu@intel.… - Separate HWPT alloc/destroy/abort functions between user-managed HWPTs and kernel-managed HWPTs - Rework invalidate uAPI to be a multi-request array-based design - Add a struct iommu_user_data_array and a helper for driver to sanitize and copy the entry data from user space invalidation array - Add a patch fixing TEST_LENGTH() in selftest program - Drop IOMMU_RESV_IOVA_RANGES patches - Update kdoc and inline comments - Drop the code to add IOMMU_RESV_SW_MSI to kernel-managed HWPT in nested translation, this does not change the rule that resv regions should only be added to the kernel-managed HWPT. The IOMMU_RESV_SW_MSI stuff will be added in later series as it is needed only by SMMU so far. v3: https://lore.kernel.org/linux-iommu/20230724110406.107212-1-yi.l.liu@intel.… - Add new uAPI things in alphabetical order - Pass in "enum iommu_hwpt_type hwpt_type" to op->domain_alloc_user for sanity, replacing the previous op->domain_alloc_user_data_len solution - Return ERR_PTR from domain_alloc_user instead of NULL - Only add IOMMU_RESV_SW_MSI to kernel-managed HWPT in nested translation (Kevin) - Add IOMMU_RESV_IOVA_RANGES to report resv iova ranges to userspace hence userspace is able to exclude the ranges in the stage-1 HWPT (e.g. guest I/O page table). (Kevin) - Add selftest coverage for the new IOMMU_RESV_IOVA_RANGES ioctl - Minor changes per Kevin's inputs v2: https://lore.kernel.org/linux-iommu/20230511143844.22693-1-yi.l.liu@intel.c… - Add union iommu_domain_user_data to include all user data structures to avoid passing void * in kernel APIs. - Add iommu op to return user data length for user domain allocation - Rename struct iommu_hwpt_alloc::data_type to be hwpt_type - Store the invalidation data length in iommu_domain_ops::cache_invalidate_user_data_len - Convert cache_invalidate_user op to be int instead of void - Remove @data_type in struct iommu_hwpt_invalidate - Remove out_hwpt_type_bitmap in struct iommu_hw_info hence drop patch 08 of v1 v1: https://lore.kernel.org/linux-iommu/20230309080910.607396-1-yi.l.liu@intel.… Thanks, Yi Liu Lu Baolu (1): iommu: Add cache_invalidate_user op Nicolin Chen (4): iommu: Add iommu_copy_struct_from_user_array helper iommufd/selftest: Add mock_domain_cache_invalidate_user support iommufd/selftest: Add IOMMU_TEST_OP_MD_CHECK_IOTLB test op iommufd/selftest: Add coverage for IOMMU_HWPT_INVALIDATE ioctl Yi Liu (1): iommufd: Add IOMMU_HWPT_INVALIDATE drivers/iommu/iommufd/hw_pagetable.c | 35 ++++++++ drivers/iommu/iommufd/iommufd_private.h | 9 ++ drivers/iommu/iommufd/iommufd_test.h | 22 +++++ drivers/iommu/iommufd/main.c | 3 + drivers/iommu/iommufd/selftest.c | 69 +++++++++++++++ include/linux/iommu.h | 84 +++++++++++++++++++ include/uapi/linux/iommufd.h | 35 ++++++++ tools/testing/selftests/iommu/iommufd.c | 75 +++++++++++++++++ tools/testing/selftests/iommu/iommufd_utils.h | 63 ++++++++++++++ 9 files changed, 395 insertions(+) -- 2.34.1

4 months

9
92
0 0

2024

2023

2022

2021

2020

2019

2018

2017

Linux-kselftest-mirror November 2023