This patch series adds a some not yet picked selftests to the kvm s390x selftest suite.
The additional test cases are covering: * Assert KVM_EXIT_S390_UCONTROL exit on not mapped memory access * Assert functionality of storage keys in ucontrol VM * Assert that memory region operations are rejected for ucontrol VMs
Running the test cases requires sys_admin capabilities to start the ucontrol VM. This can be achieved by running as root or with a command like:
sudo setpriv --reuid nobody --inh-caps -all,+sys_admin \ --ambient-caps -all,+sys_admin --bounding-set -all,+sys_admin \ ./ucontrol_test
---
The patches in this series have been part of the previous patch series. The test cases added here do depend on the fixture added in the earlier patches. From v5 PATCH 7-9 the segment and page table generation has been removed and DAT has been disabled. Since DAT is not necessary to validate the KVM code.
https://lore.kernel.org/kvm/20240807154512.316936-1-schlameuss@linux.ibm.com...
v6: - add instruction intercept handling for skey specific instructions (iske, sske, rrbe) in addition to kss intercept to work properly on all machines - reorder local variables - fixup some method comments - add a patch correcting the IP.b value length a debug message
v5: - rebased to current upstream master - corrected assertion on 0x00 to 0 - reworded fixup commit so that it can be merged on top of current upstream
v4: - fix whitespaces in pointer function arguments (thanks Claudio) - fix whitespaces in comments (thanks Janosch)
v3: - fix skey assertion (thanks Claudio) - introduce a wrapper around UCAS map and unmap ioctls to improve readability (Claudio) - add an displacement to accessed memory to assert translation intercepts actually point to segments to the uc_map_unmap test - add an misaligned failing mapping try to the uc_map_unmap test
v2: - Reenable KSS intercept and handle it within skey test. - Modify the checked register between storing (sske) and reading (iske) it within the test program to make sure the. - Add an additional state assertion in the end of uc_skey - Fix some typos and white spaces.
v1: - Remove segment and page table generation and disable DAT. This is not necessary to validate the KVM code.
Christoph Schlameuss (5): selftests: kvm: s390: Add uc_map_unmap VM test case selftests: kvm: s390: Add uc_skey VM test case selftests: kvm: s390: Verify reject memory region operations for ucontrol VMs selftests: kvm: s390: Fix whitespace confusion in ucontrol test selftests: kvm: s390: correct IP.b length in uc_handle_sieic debug output
.../selftests/kvm/include/s390x/processor.h | 6 + .../selftests/kvm/s390x/ucontrol_test.c | 307 +++++++++++++++++- 2 files changed, 305 insertions(+), 8 deletions(-)
base-commit: eca631b8fe808748d7585059c4307005ca5c5820
Add a test case verifying basic running and interaction of ucontrol VMs. Fill the segment and page tables for allocated memory and map memory on first access.
* uc_map_unmap Store and load data to mapped and unmapped memory and use pic segment translation handling to map memory on access.
Signed-off-by: Christoph Schlameuss schlameuss@linux.ibm.com Reviewed-by: Janosch Frank frankja@linux.ibm.com --- .../selftests/kvm/s390x/ucontrol_test.c | 145 +++++++++++++++++- 1 file changed, 144 insertions(+), 1 deletion(-)
diff --git a/tools/testing/selftests/kvm/s390x/ucontrol_test.c b/tools/testing/selftests/kvm/s390x/ucontrol_test.c index f257beec1430..3e649b12a0b9 100644 --- a/tools/testing/selftests/kvm/s390x/ucontrol_test.c +++ b/tools/testing/selftests/kvm/s390x/ucontrol_test.c @@ -16,7 +16,11 @@ #include <linux/capability.h> #include <linux/sizes.h>
+#define PGM_SEGMENT_TRANSLATION 0x10 + #define VM_MEM_SIZE (4 * SZ_1M) +#define VM_MEM_EXT_SIZE (2 * SZ_1M) +#define VM_MEM_MAX_M ((VM_MEM_SIZE + VM_MEM_EXT_SIZE) / SZ_1M)
/* so directly declare capget to check caps without libcap */ int capget(cap_user_header_t header, cap_user_data_t data); @@ -58,6 +62,23 @@ asm("test_gprs_asm:\n" " j 0b\n" );
+/* Test program manipulating memory */ +extern char test_mem_asm[]; +asm("test_mem_asm:\n" + "xgr %r0, %r0\n" + + "0:\n" + " ahi %r0,1\n" + " st %r1,0(%r5,%r6)\n" + + " xgr %r1,%r1\n" + " l %r1,0(%r5,%r6)\n" + " ahi %r0,1\n" + " diag 0,0,0x44\n" + + " j 0b\n" +); + FIXTURE(uc_kvm) { struct kvm_s390_sie_block *sie_block; @@ -67,6 +88,7 @@ FIXTURE(uc_kvm) uintptr_t base_hva; uintptr_t code_hva; int kvm_run_size; + vm_paddr_t pgd; void *vm_mem; int vcpu_fd; int kvm_fd; @@ -116,7 +138,7 @@ FIXTURE_SETUP(uc_kvm) self->base_gpa = 0; self->code_gpa = self->base_gpa + (3 * SZ_1M);
- self->vm_mem = aligned_alloc(SZ_1M, VM_MEM_SIZE); + self->vm_mem = aligned_alloc(SZ_1M, VM_MEM_MAX_M * SZ_1M); ASSERT_NE(NULL, self->vm_mem) TH_LOG("malloc failed %u", errno); self->base_hva = (uintptr_t)self->vm_mem; self->code_hva = self->base_hva - self->base_gpa + self->code_gpa; @@ -222,6 +244,60 @@ TEST(uc_cap_hpage) close(kvm_fd); }
+/* calculate host virtual addr from guest physical addr */ +static void *gpa2hva(FIXTURE_DATA(uc_kvm) *self, u64 gpa) +{ + return (void *)(self->base_hva - self->base_gpa + gpa); +} + +/* map / make additional memory available */ +static int uc_map_ext(FIXTURE_DATA(uc_kvm) *self, u64 vcpu_addr, u64 length) +{ + struct kvm_s390_ucas_mapping map = { + .user_addr = (u64)gpa2hva(self, vcpu_addr), + .vcpu_addr = vcpu_addr, + .length = length, + }; + pr_info("ucas map %p %p 0x%llx", + (void *)map.user_addr, (void *)map.vcpu_addr, map.length); + return ioctl(self->vcpu_fd, KVM_S390_UCAS_MAP, &map); +} + +/* unmap previously mapped memory */ +static int uc_unmap_ext(FIXTURE_DATA(uc_kvm) *self, u64 vcpu_addr, u64 length) +{ + struct kvm_s390_ucas_mapping map = { + .user_addr = (u64)gpa2hva(self, vcpu_addr), + .vcpu_addr = vcpu_addr, + .length = length, + }; + pr_info("ucas unmap %p %p 0x%llx", + (void *)map.user_addr, (void *)map.vcpu_addr, map.length); + return ioctl(self->vcpu_fd, KVM_S390_UCAS_UNMAP, &map); +} + +/* handle ucontrol exit by mapping the accessed segment */ +static void uc_handle_exit_ucontrol(FIXTURE_DATA(uc_kvm) *self) +{ + struct kvm_run *run = self->run; + u64 seg_addr; + int rc; + + TEST_ASSERT_EQ(KVM_EXIT_S390_UCONTROL, run->exit_reason); + switch (run->s390_ucontrol.pgm_code) { + case PGM_SEGMENT_TRANSLATION: + seg_addr = run->s390_ucontrol.trans_exc_code & ~(SZ_1M - 1); + pr_info("ucontrol pic segment translation 0x%llx, mapping segment 0x%lx\n", + run->s390_ucontrol.trans_exc_code, seg_addr); + /* map / make additional memory available */ + rc = uc_map_ext(self, seg_addr, SZ_1M); + TEST_ASSERT_EQ(0, rc); + break; + default: + TEST_FAIL("UNEXPECTED PGM CODE %d", run->s390_ucontrol.pgm_code); + } +} + /* verify SIEIC exit * * fail on codes not expected in the test cases */ @@ -255,6 +331,12 @@ static bool uc_handle_exit(FIXTURE_DATA(uc_kvm) * self) struct kvm_run *run = self->run;
switch (run->exit_reason) { + case KVM_EXIT_S390_UCONTROL: + /** check program interruption code + * handle page fault --> ucas map + */ + uc_handle_exit_ucontrol(self); + break; case KVM_EXIT_S390_SIEIC: return uc_handle_sieic(self); default: @@ -286,6 +368,67 @@ static void uc_assert_diag44(FIXTURE_DATA(uc_kvm) * self) TEST_ASSERT_EQ(0x440000, sie_block->ipb); }
+TEST_F(uc_kvm, uc_map_unmap) +{ + struct kvm_sync_regs *sync_regs = &self->run->s.regs; + struct kvm_run *run = self->run; + const u64 disp = 1; + int rc; + + /* copy test_mem_asm to code_hva / code_gpa */ + TH_LOG("copy code %p to vm mapped memory %p / %p", + &test_mem_asm, (void *)self->code_hva, (void *)self->code_gpa); + memcpy((void *)self->code_hva, &test_mem_asm, PAGE_SIZE); + + /* DAT disabled + 64 bit mode */ + run->psw_mask = 0x0000000180000000ULL; + run->psw_addr = self->code_gpa; + + /* set register content for test_mem_asm to access not mapped memory*/ + sync_regs->gprs[1] = 0x55; + sync_regs->gprs[5] = self->base_gpa; + sync_regs->gprs[6] = VM_MEM_SIZE + disp; + run->kvm_dirty_regs |= KVM_SYNC_GPRS; + + /* run and expect to fail with ucontrol pic segment translation */ + ASSERT_EQ(0, uc_run_once(self)); + ASSERT_EQ(1, sync_regs->gprs[0]); + ASSERT_EQ(KVM_EXIT_S390_UCONTROL, run->exit_reason); + + ASSERT_EQ(PGM_SEGMENT_TRANSLATION, run->s390_ucontrol.pgm_code); + ASSERT_EQ(self->base_gpa + VM_MEM_SIZE, run->s390_ucontrol.trans_exc_code); + + /* fail to map memory with not segment aligned address */ + rc = uc_map_ext(self, self->base_gpa + VM_MEM_SIZE + disp, VM_MEM_EXT_SIZE); + ASSERT_GT(0, rc) + TH_LOG("ucas map for non segment address should fail but didn't; " + "result %d not expected, %s", rc, strerror(errno)); + + /* map / make additional memory available */ + rc = uc_map_ext(self, self->base_gpa + VM_MEM_SIZE, VM_MEM_EXT_SIZE); + ASSERT_EQ(0, rc) + TH_LOG("ucas map result %d not expected, %s", rc, strerror(errno)); + ASSERT_EQ(0, uc_run_once(self)); + ASSERT_EQ(false, uc_handle_exit(self)); + uc_assert_diag44(self); + + /* assert registers and memory are in expected state */ + ASSERT_EQ(2, sync_regs->gprs[0]); + ASSERT_EQ(0x55, sync_regs->gprs[1]); + ASSERT_EQ(0x55, *(u32 *)gpa2hva(self, self->base_gpa + VM_MEM_SIZE + disp)); + + /* unmap and run loop again */ + rc = uc_unmap_ext(self, self->base_gpa + VM_MEM_SIZE, VM_MEM_EXT_SIZE); + ASSERT_EQ(0, rc) + TH_LOG("ucas unmap result %d not expected, %s", rc, strerror(errno)); + ASSERT_EQ(0, uc_run_once(self)); + ASSERT_EQ(3, sync_regs->gprs[0]); + ASSERT_EQ(KVM_EXIT_S390_UCONTROL, run->exit_reason); + ASSERT_EQ(PGM_SEGMENT_TRANSLATION, run->s390_ucontrol.pgm_code); + /* handle ucontrol exit and remap memory after previous map and unmap */ + ASSERT_EQ(true, uc_handle_exit(self)); +} + TEST_F(uc_kvm, uc_gprs) { struct kvm_sync_regs *sync_regs = &self->run->s.regs;
Add a test case manipulating s390 storage keys from within the ucontrol VM.
Storage key instruction (ISKE, SSKE and RRBE) intercepts and Keyless-subset facility are disabled on first use, where the skeys are setup by KVM in non ucontrol VMs.
Signed-off-by: Christoph Schlameuss schlameuss@linux.ibm.com --- .../selftests/kvm/include/s390x/processor.h | 6 + .../selftests/kvm/s390x/ucontrol_test.c | 130 +++++++++++++++++- 2 files changed, 134 insertions(+), 2 deletions(-)
diff --git a/tools/testing/selftests/kvm/include/s390x/processor.h b/tools/testing/selftests/kvm/include/s390x/processor.h index 481bd2fd6a32..33fef6fd9617 100644 --- a/tools/testing/selftests/kvm/include/s390x/processor.h +++ b/tools/testing/selftests/kvm/include/s390x/processor.h @@ -32,4 +32,10 @@ static inline void cpu_relax(void) barrier(); }
+/* Get the instruction length */ +static inline int insn_length(unsigned char code) +{ + return ((((int)code + 64) >> 7) + 1) << 1; +} + #endif diff --git a/tools/testing/selftests/kvm/s390x/ucontrol_test.c b/tools/testing/selftests/kvm/s390x/ucontrol_test.c index 3e649b12a0b9..9568a4e03e4b 100644 --- a/tools/testing/selftests/kvm/s390x/ucontrol_test.c +++ b/tools/testing/selftests/kvm/s390x/ucontrol_test.c @@ -79,6 +79,33 @@ asm("test_mem_asm:\n" " j 0b\n" );
+/* Test program manipulating storage keys */ +extern char test_skey_asm[]; +asm("test_skey_asm:\n" + "xgr %r0, %r0\n" + + "0:\n" + " ahi %r0,1\n" + " st %r1,0(%r5,%r6)\n" + + " iske %r1,%r6\n" + " ahi %r0,1\n" + " diag 0,0,0x44\n" + + " sske %r1,%r6\n" + " xgr %r1,%r1\n" + " iske %r1,%r6\n" + " ahi %r0,1\n" + " diag 0,0,0x44\n" + + " rrbe %r1,%r6\n" + " iske %r1,%r6\n" + " ahi %r0,1\n" + " diag 0,0,0x44\n" + + " j 0b\n" +); + FIXTURE(uc_kvm) { struct kvm_s390_sie_block *sie_block; @@ -298,8 +325,49 @@ static void uc_handle_exit_ucontrol(FIXTURE_DATA(uc_kvm) *self) } }
-/* verify SIEIC exit +/* + * Disable skey intercepts and rewind last instruction + * (KVM would init the skeys here) + */ +static void uc_skey_enable(FIXTURE_DATA(uc_kvm) *self) +{ + struct kvm_s390_sie_block *sie_block = self->sie_block; + int ilen = insn_length(sie_block->ipa >> 8); + struct kvm_run *run = self->run; + + /* disable KSS */ + sie_block->cpuflags &= ~CPUSTAT_KSS; + /* disable skey inst interception */ + sie_block->ictl &= ~(ICTL_ISKE | ICTL_SSKE | ICTL_RRBE); + + /* rewind to reexecute intercepted instruction */ + run->psw_addr = run->psw_addr - ilen; + pr_info("rewind guest addr to 0x%.16llx\n", run->psw_addr); +} + +/* + * Handle the instruction intercept + * Returns if interception is handled / execution can be continued + */ +static bool uc_handle_insn_ic(FIXTURE_DATA(uc_kvm) *self) +{ + struct kvm_run *run = self->run; + + switch (run->s390_sieic.ipa) { + case 0xB229: /* ISKE */ + case 0xB22b: /* SSKE */ + case 0xB22a: /* RRBE */ + uc_skey_enable(self); + return true; + default: + return false; + } +} + +/* + * Handle the SIEIC exit * * fail on codes not expected in the test cases + * Returns if interception is handled / execution can be continued */ static bool uc_handle_sieic(FIXTURE_DATA(uc_kvm) * self) { @@ -315,7 +383,10 @@ static bool uc_handle_sieic(FIXTURE_DATA(uc_kvm) * self) case ICPT_INST: /* end execution in caller on intercepted instruction */ pr_info("sie instruction interception\n"); - return false; + return uc_handle_insn_ic(self); + case ICPT_KSS: + uc_skey_enable(self); + return true; case ICPT_OPEREXC: /* operation exception */ TEST_FAIL("sie exception on %.4x%.8x", sie_block->ipa, sie_block->ipb); @@ -472,4 +543,59 @@ TEST_F(uc_kvm, uc_gprs) ASSERT_EQ(1, sync_regs->gprs[0]); }
+TEST_F(uc_kvm, uc_skey) +{ + struct kvm_sync_regs *sync_regs = &self->run->s.regs; + u64 test_vaddr = VM_MEM_SIZE - (SZ_1M / 2); + struct kvm_run *run = self->run; + const u8 skeyvalue = 0x34; + + /* copy test_skey_asm to code_hva / code_gpa */ + TH_LOG("copy code %p to vm mapped memory %p / %p", + &test_skey_asm, (void *)self->code_hva, (void *)self->code_gpa); + memcpy((void *)self->code_hva, &test_skey_asm, PAGE_SIZE); + + /* set register content for test_skey_asm to access not mapped memory */ + sync_regs->gprs[1] = skeyvalue; + sync_regs->gprs[5] = self->base_gpa; + sync_regs->gprs[6] = test_vaddr; + run->kvm_dirty_regs |= KVM_SYNC_GPRS; + + /* DAT disabled + 64 bit mode */ + run->psw_mask = 0x0000000180000000ULL; + run->psw_addr = self->code_gpa; + + ASSERT_EQ(0, uc_run_once(self)); + ASSERT_EQ(true, uc_handle_exit(self)); + ASSERT_EQ(1, sync_regs->gprs[0]); + + /* ISKE */ + ASSERT_EQ(0, uc_run_once(self)); + ASSERT_EQ(false, uc_handle_exit(self)); + ASSERT_EQ(2, sync_regs->gprs[0]); + /* assert initial skey (ACC = 0, R & C = 1) */ + ASSERT_EQ(0x06, sync_regs->gprs[1]); + uc_assert_diag44(self); + + /* SSKE + ISKE */ + sync_regs->gprs[1] = skeyvalue; + run->kvm_dirty_regs |= KVM_SYNC_GPRS; + ASSERT_EQ(0, uc_run_once(self)); + ASSERT_EQ(false, uc_handle_exit(self)); + ASSERT_EQ(3, sync_regs->gprs[0]); + ASSERT_EQ(skeyvalue, sync_regs->gprs[1]); + uc_assert_diag44(self); + + /* RRBE + ISKE */ + sync_regs->gprs[1] = skeyvalue; + run->kvm_dirty_regs |= KVM_SYNC_GPRS; + ASSERT_EQ(0, uc_run_once(self)); + ASSERT_EQ(false, uc_handle_exit(self)); + ASSERT_EQ(4, sync_regs->gprs[0]); + /* assert R reset but rest of skey unchanged */ + ASSERT_EQ(skeyvalue & 0xfa, sync_regs->gprs[1]); + ASSERT_EQ(0, sync_regs->gprs[1] & 0x04); + uc_assert_diag44(self); +} + TEST_HARNESS_MAIN
On 10/15/24 10:37 AM, Christoph Schlameuss wrote:
Add a test case manipulating s390 storage keys from within the ucontrol VM.
Storage key instruction (ISKE, SSKE and RRBE) intercepts and Keyless-subset facility are disabled on first use, where the skeys are setup by KVM in non ucontrol VMs.
[...]
-/* verify SIEIC exit +/*
- Disable skey intercepts and rewind last instruction
- (KVM would init the skeys here)
- */
+static void uc_skey_enable(FIXTURE_DATA(uc_kvm) *self) +{
- struct kvm_s390_sie_block *sie_block = self->sie_block;
- int ilen = insn_length(sie_block->ipa >> 8);
- struct kvm_run *run = self->run;
- /* disable KSS */
- sie_block->cpuflags &= ~CPUSTAT_KSS;
- /* disable skey inst interception */
- sie_block->ictl &= ~(ICTL_ISKE | ICTL_SSKE | ICTL_RRBE);
- /* rewind to reexecute intercepted instruction */
- run->psw_addr = run->psw_addr - ilen;
There's a very important detail between KSS and the SKEY ICTLs: KSS is (mostly) nullifying i.e. the PSW points to the instruction that caused the KSS exit. ICTL intercepts are suppressing which means the PSW points after the instruction and hence we need to rewind the PSW if we want to re-issue the instruction.
Re-winding on a KSS intercept makes the guest cpu execute the instruction before the intercept producing instruction twice.
On Tue Oct 15, 2024 at 3:22 PM CEST, Janosch Frank wrote:
On 10/15/24 10:37 AM, Christoph Schlameuss wrote:
Add a test case manipulating s390 storage keys from within the ucontrol VM.
Storage key instruction (ISKE, SSKE and RRBE) intercepts and Keyless-subset facility are disabled on first use, where the skeys are setup by KVM in non ucontrol VMs.
[...]
-/* verify SIEIC exit +/*
- Disable skey intercepts and rewind last instruction
- (KVM would init the skeys here)
- */
+static void uc_skey_enable(FIXTURE_DATA(uc_kvm) *self) +{
- struct kvm_s390_sie_block *sie_block = self->sie_block;
- int ilen = insn_length(sie_block->ipa >> 8);
- struct kvm_run *run = self->run;
- /* disable KSS */
- sie_block->cpuflags &= ~CPUSTAT_KSS;
- /* disable skey inst interception */
- sie_block->ictl &= ~(ICTL_ISKE | ICTL_SSKE | ICTL_RRBE);
- /* rewind to reexecute intercepted instruction */
- run->psw_addr = run->psw_addr - ilen;
There's a very important detail between KSS and the SKEY ICTLs: KSS is (mostly) nullifying i.e. the PSW points to the instruction that caused the KSS exit. ICTL intercepts are suppressing which means the PSW points after the instruction and hence we need to rewind the PSW if we want to re-issue the instruction.
Re-winding on a KSS intercept makes the guest cpu execute the instruction before the intercept producing instruction twice.
Oh, yes. You are right, I did mess that up in my cleanup. I will fix that. Here it does now only work since the KSS is not intercepted on the second invocation. But I am with you, it should only be executed once.
Add a test case manipulating s390 storage keys from within the ucontrol VM.
Storage key instruction (ISKE, SSKE and RRBE) intercepts and Keyless-subset facility are disabled on first use, where the skeys are setup by KVM in non ucontrol VMs.
Signed-off-by: Christoph Schlameuss schlameuss@linux.ibm.com --- .../selftests/kvm/include/s390x/processor.h | 6 + .../selftests/kvm/s390x/ucontrol_test.c | 130 +++++++++++++++++- 2 files changed, 134 insertions(+), 2 deletions(-)
diff --git a/tools/testing/selftests/kvm/include/s390x/processor.h b/tools/testing/selftests/kvm/include/s390x/processor.h index 481bd2fd6a32..33fef6fd9617 100644 --- a/tools/testing/selftests/kvm/include/s390x/processor.h +++ b/tools/testing/selftests/kvm/include/s390x/processor.h @@ -32,4 +32,10 @@ static inline void cpu_relax(void) barrier(); }
+/* Get the instruction length */ +static inline int insn_length(unsigned char code) +{ + return ((((int)code + 64) >> 7) + 1) << 1; +} + #endif diff --git a/tools/testing/selftests/kvm/s390x/ucontrol_test.c b/tools/testing/selftests/kvm/s390x/ucontrol_test.c index 3e649b12a0b9..9568a4e03e4b 100644 --- a/tools/testing/selftests/kvm/s390x/ucontrol_test.c +++ b/tools/testing/selftests/kvm/s390x/ucontrol_test.c @@ -79,6 +79,33 @@ asm("test_mem_asm:\n" " j 0b\n" );
+/* Test program manipulating storage keys */ +extern char test_skey_asm[]; +asm("test_skey_asm:\n" + "xgr %r0, %r0\n" + + "0:\n" + " ahi %r0,1\n" + " st %r1,0(%r5,%r6)\n" + + " iske %r1,%r6\n" + " ahi %r0,1\n" + " diag 0,0,0x44\n" + + " sske %r1,%r6\n" + " xgr %r1,%r1\n" + " iske %r1,%r6\n" + " ahi %r0,1\n" + " diag 0,0,0x44\n" + + " rrbe %r1,%r6\n" + " iske %r1,%r6\n" + " ahi %r0,1\n" + " diag 0,0,0x44\n" + + " j 0b\n" +); + FIXTURE(uc_kvm) { struct kvm_s390_sie_block *sie_block; @@ -298,8 +325,49 @@ static void uc_handle_exit_ucontrol(FIXTURE_DATA(uc_kvm) *self) } }
-/* verify SIEIC exit +/* + * Disable skey intercepts and rewind last instruction + * (KVM would init the skeys here) + */ +static void uc_skey_enable(FIXTURE_DATA(uc_kvm) *self) +{ + struct kvm_s390_sie_block *sie_block = self->sie_block; + int ilen = insn_length(sie_block->ipa >> 8); + struct kvm_run *run = self->run; + + /* disable KSS */ + sie_block->cpuflags &= ~CPUSTAT_KSS; + /* disable skey inst interception */ + sie_block->ictl &= ~(ICTL_ISKE | ICTL_SSKE | ICTL_RRBE); + + /* rewind to reexecute intercepted instruction */ + run->psw_addr = run->psw_addr - ilen; + pr_info("rewind guest addr to 0x%.16llx\n", run->psw_addr); +} + +/* + * Handle the instruction intercept + * Returns if interception is handled / execution can be continued + */ +static bool uc_handle_insn_ic(FIXTURE_DATA(uc_kvm) *self) +{ + struct kvm_run *run = self->run; + + switch (run->s390_sieic.ipa) { + case 0xB229: /* ISKE */ + case 0xB22b: /* SSKE */ + case 0xB22a: /* RRBE */ + uc_skey_enable(self); + return true; + default: + return false; + } +} + +/* + * Handle the SIEIC exit * * fail on codes not expected in the test cases + * Returns if interception is handled / execution can be continued */ static bool uc_handle_sieic(FIXTURE_DATA(uc_kvm) * self) { @@ -315,7 +383,10 @@ static bool uc_handle_sieic(FIXTURE_DATA(uc_kvm) * self) case ICPT_INST: /* end execution in caller on intercepted instruction */ pr_info("sie instruction interception\n"); - return false; + return uc_handle_insn_ic(self); + case ICPT_KSS: + uc_skey_enable(self); + return true; case ICPT_OPEREXC: /* operation exception */ TEST_FAIL("sie exception on %.4x%.8x", sie_block->ipa, sie_block->ipb); @@ -472,4 +543,59 @@ TEST_F(uc_kvm, uc_gprs) ASSERT_EQ(1, sync_regs->gprs[0]); }
+TEST_F(uc_kvm, uc_skey) +{ + struct kvm_sync_regs *sync_regs = &self->run->s.regs; + u64 test_vaddr = VM_MEM_SIZE - (SZ_1M / 2); + struct kvm_run *run = self->run; + const u8 skeyvalue = 0x34; + + /* copy test_skey_asm to code_hva / code_gpa */ + TH_LOG("copy code %p to vm mapped memory %p / %p", + &test_skey_asm, (void *)self->code_hva, (void *)self->code_gpa); + memcpy((void *)self->code_hva, &test_skey_asm, PAGE_SIZE); + + /* set register content for test_skey_asm to access not mapped memory */ + sync_regs->gprs[1] = skeyvalue; + sync_regs->gprs[5] = self->base_gpa; + sync_regs->gprs[6] = test_vaddr; + run->kvm_dirty_regs |= KVM_SYNC_GPRS; + + /* DAT disabled + 64 bit mode */ + run->psw_mask = 0x0000000180000000ULL; + run->psw_addr = self->code_gpa; + + ASSERT_EQ(0, uc_run_once(self)); + ASSERT_EQ(true, uc_handle_exit(self)); + ASSERT_EQ(1, sync_regs->gprs[0]); + + /* ISKE */ + ASSERT_EQ(0, uc_run_once(self)); + ASSERT_EQ(false, uc_handle_exit(self)); + ASSERT_EQ(2, sync_regs->gprs[0]); + /* assert initial skey (ACC = 0, R & C = 1) */ + ASSERT_EQ(0x06, sync_regs->gprs[1]); + uc_assert_diag44(self); + + /* SSKE + ISKE */ + sync_regs->gprs[1] = skeyvalue; + run->kvm_dirty_regs |= KVM_SYNC_GPRS; + ASSERT_EQ(0, uc_run_once(self)); + ASSERT_EQ(false, uc_handle_exit(self)); + ASSERT_EQ(3, sync_regs->gprs[0]); + ASSERT_EQ(skeyvalue, sync_regs->gprs[1]); + uc_assert_diag44(self); + + /* RRBE + ISKE */ + sync_regs->gprs[1] = skeyvalue; + run->kvm_dirty_regs |= KVM_SYNC_GPRS; + ASSERT_EQ(0, uc_run_once(self)); + ASSERT_EQ(false, uc_handle_exit(self)); + ASSERT_EQ(4, sync_regs->gprs[0]); + /* assert R reset but rest of skey unchanged */ + ASSERT_EQ(skeyvalue & 0xfa, sync_regs->gprs[1]); + ASSERT_EQ(0, sync_regs->gprs[1] & 0x04); + uc_assert_diag44(self); +} + TEST_HARNESS_MAIN
Please ignore this one. I tricked myself in my patch generation and regenerated the original patch.
Add a test case manipulating s390 storage keys from within the ucontrol VM.
Storage key instruction (ISKE, SSKE and RRBE) intercepts and Keyless-subset facility are disabled on first use, where the skeys are setup by KVM in non ucontrol VMs.
Signed-off-by: Christoph Schlameuss schlameuss@linux.ibm.com --- .../selftests/kvm/include/s390x/processor.h | 6 + .../selftests/kvm/s390x/ucontrol_test.c | 130 +++++++++++++++++- 2 files changed, 134 insertions(+), 2 deletions(-)
diff --git a/tools/testing/selftests/kvm/include/s390x/processor.h b/tools/testing/selftests/kvm/include/s390x/processor.h index 481bd2fd6a32..33fef6fd9617 100644 --- a/tools/testing/selftests/kvm/include/s390x/processor.h +++ b/tools/testing/selftests/kvm/include/s390x/processor.h @@ -32,4 +32,10 @@ static inline void cpu_relax(void) barrier(); }
+/* Get the instruction length */ +static inline int insn_length(unsigned char code) +{ + return ((((int)code + 64) >> 7) + 1) << 1; +} + #endif diff --git a/tools/testing/selftests/kvm/s390x/ucontrol_test.c b/tools/testing/selftests/kvm/s390x/ucontrol_test.c index 3e649b12a0b9..c1bc199d6e85 100644 --- a/tools/testing/selftests/kvm/s390x/ucontrol_test.c +++ b/tools/testing/selftests/kvm/s390x/ucontrol_test.c @@ -79,6 +79,33 @@ asm("test_mem_asm:\n" " j 0b\n" );
+/* Test program manipulating storage keys */ +extern char test_skey_asm[]; +asm("test_skey_asm:\n" + "xgr %r0, %r0\n" + + "0:\n" + " ahi %r0,1\n" + " st %r1,0(%r5,%r6)\n" + + " iske %r1,%r6\n" + " ahi %r0,1\n" + " diag 0,0,0x44\n" + + " sske %r1,%r6\n" + " xgr %r1,%r1\n" + " iske %r1,%r6\n" + " ahi %r0,1\n" + " diag 0,0,0x44\n" + + " rrbe %r1,%r6\n" + " iske %r1,%r6\n" + " ahi %r0,1\n" + " diag 0,0,0x44\n" + + " j 0b\n" +); + FIXTURE(uc_kvm) { struct kvm_s390_sie_block *sie_block; @@ -298,8 +325,49 @@ static void uc_handle_exit_ucontrol(FIXTURE_DATA(uc_kvm) *self) } }
-/* verify SIEIC exit +/* + * Disable skey intercepts + * (KVM would init the skeys here) + */ +static void uc_skey_enable(FIXTURE_DATA(uc_kvm) *self) +{ + struct kvm_s390_sie_block *sie_block = self->sie_block; + + /* disable KSS */ + sie_block->cpuflags &= ~CPUSTAT_KSS; + /* disable skey inst interception */ + sie_block->ictl &= ~(ICTL_ISKE | ICTL_SSKE | ICTL_RRBE); +} + +/* + * Handle the instruction intercept + * Returns if interception is handled / execution can be continued + */ +static bool uc_handle_insn_ic(FIXTURE_DATA(uc_kvm) *self) +{ + struct kvm_s390_sie_block *sie_block = self->sie_block; + int ilen = insn_length(sie_block->ipa >> 8); + struct kvm_run *run = self->run; + + switch (run->s390_sieic.ipa) { + case 0xB229: /* ISKE */ + case 0xB22b: /* SSKE */ + case 0xB22a: /* RRBE */ + uc_skey_enable(self); + + /* rewind to reexecute intercepted instruction */ + run->psw_addr = run->psw_addr - ilen; + pr_info("rewind guest addr to 0x%.16llx\n", run->psw_addr); + return true; + default: + return false; + } +} + +/* + * Handle the SIEIC exit * * fail on codes not expected in the test cases + * Returns if interception is handled / execution can be continued */ static bool uc_handle_sieic(FIXTURE_DATA(uc_kvm) * self) { @@ -315,7 +383,10 @@ static bool uc_handle_sieic(FIXTURE_DATA(uc_kvm) * self) case ICPT_INST: /* end execution in caller on intercepted instruction */ pr_info("sie instruction interception\n"); - return false; + return uc_handle_insn_ic(self); + case ICPT_KSS: + uc_skey_enable(self); + return true; case ICPT_OPEREXC: /* operation exception */ TEST_FAIL("sie exception on %.4x%.8x", sie_block->ipa, sie_block->ipb); @@ -472,4 +543,59 @@ TEST_F(uc_kvm, uc_gprs) ASSERT_EQ(1, sync_regs->gprs[0]); }
+TEST_F(uc_kvm, uc_skey) +{ + struct kvm_sync_regs *sync_regs = &self->run->s.regs; + u64 test_vaddr = VM_MEM_SIZE - (SZ_1M / 2); + struct kvm_run *run = self->run; + const u8 skeyvalue = 0x34; + + /* copy test_skey_asm to code_hva / code_gpa */ + TH_LOG("copy code %p to vm mapped memory %p / %p", + &test_skey_asm, (void *)self->code_hva, (void *)self->code_gpa); + memcpy((void *)self->code_hva, &test_skey_asm, PAGE_SIZE); + + /* set register content for test_skey_asm to access not mapped memory */ + sync_regs->gprs[1] = skeyvalue; + sync_regs->gprs[5] = self->base_gpa; + sync_regs->gprs[6] = test_vaddr; + run->kvm_dirty_regs |= KVM_SYNC_GPRS; + + /* DAT disabled + 64 bit mode */ + run->psw_mask = 0x0000000180000000ULL; + run->psw_addr = self->code_gpa; + + ASSERT_EQ(0, uc_run_once(self)); + ASSERT_EQ(true, uc_handle_exit(self)); + ASSERT_EQ(1, sync_regs->gprs[0]); + + /* ISKE */ + ASSERT_EQ(0, uc_run_once(self)); + ASSERT_EQ(false, uc_handle_exit(self)); + ASSERT_EQ(2, sync_regs->gprs[0]); + /* assert initial skey (ACC = 0, R & C = 1) */ + ASSERT_EQ(0x06, sync_regs->gprs[1]); + uc_assert_diag44(self); + + /* SSKE + ISKE */ + sync_regs->gprs[1] = skeyvalue; + run->kvm_dirty_regs |= KVM_SYNC_GPRS; + ASSERT_EQ(0, uc_run_once(self)); + ASSERT_EQ(false, uc_handle_exit(self)); + ASSERT_EQ(3, sync_regs->gprs[0]); + ASSERT_EQ(skeyvalue, sync_regs->gprs[1]); + uc_assert_diag44(self); + + /* RRBE + ISKE */ + sync_regs->gprs[1] = skeyvalue; + run->kvm_dirty_regs |= KVM_SYNC_GPRS; + ASSERT_EQ(0, uc_run_once(self)); + ASSERT_EQ(false, uc_handle_exit(self)); + ASSERT_EQ(4, sync_regs->gprs[0]); + /* assert R reset but rest of skey unchanged */ + ASSERT_EQ(skeyvalue & 0xfa, sync_regs->gprs[1]); + ASSERT_EQ(0, sync_regs->gprs[1] & 0x04); + uc_assert_diag44(self); +} + TEST_HARNESS_MAIN
On 10/15/24 4:15 PM, Christoph Schlameuss wrote:
Add a test case manipulating s390 storage keys from within the ucontrol VM.
Storage key instruction (ISKE, SSKE and RRBE) intercepts and Keyless-subset facility are disabled on first use, where the skeys are setup by KVM in non ucontrol VMs.
Signed-off-by: Christoph Schlameuss schlameuss@linux.ibm.com
Acked-by: Janosch Frank frankja@linux.ibm.com
Add a test case verifying KVM_SET_USER_MEMORY_REGION and KVM_SET_USER_MEMORY_REGION2 cannot be executed on ucontrol VMs.
Executing this test case on not patched kernels will cause a null pointer dereference in the host kernel. This is fixed with commit: commit 7816e58967d0 ("kvm: s390: Reject memory region operations for ucontrol VMs")
Signed-off-by: Christoph Schlameuss schlameuss@linux.ibm.com Reviewed-by: Janosch Frank frankja@linux.ibm.com --- .../selftests/kvm/s390x/ucontrol_test.c | 22 +++++++++++++++++++ 1 file changed, 22 insertions(+)
diff --git a/tools/testing/selftests/kvm/s390x/ucontrol_test.c b/tools/testing/selftests/kvm/s390x/ucontrol_test.c index 9568a4e03e4b..ae077bf838c8 100644 --- a/tools/testing/selftests/kvm/s390x/ucontrol_test.c +++ b/tools/testing/selftests/kvm/s390x/ucontrol_test.c @@ -439,6 +439,28 @@ static void uc_assert_diag44(FIXTURE_DATA(uc_kvm) * self) TEST_ASSERT_EQ(0x440000, sie_block->ipb); }
+TEST_F(uc_kvm, uc_no_user_region) +{ + struct kvm_userspace_memory_region region = { + .slot = 1, + .guest_phys_addr = self->code_gpa, + .memory_size = VM_MEM_EXT_SIZE, + .userspace_addr = (uintptr_t)self->code_hva, + }; + struct kvm_userspace_memory_region2 region2 = { + .slot = 1, + .guest_phys_addr = self->code_gpa, + .memory_size = VM_MEM_EXT_SIZE, + .userspace_addr = (uintptr_t)self->code_hva, + }; + + ASSERT_EQ(-1, ioctl(self->vm_fd, KVM_SET_USER_MEMORY_REGION, ®ion)); + ASSERT_EQ(EINVAL, errno); + + ASSERT_EQ(-1, ioctl(self->vm_fd, KVM_SET_USER_MEMORY_REGION2, ®ion2)); + ASSERT_EQ(EINVAL, errno); +} + TEST_F(uc_kvm, uc_map_unmap) { struct kvm_sync_regs *sync_regs = &self->run->s.regs;
Checkpatch thinks that we're doing a multiplication but we're obviously not. Fix 4 instances where we adhered to wrong checkpatch advice.
Signed-off-by: Christoph Schlameuss schlameuss@linux.ibm.com --- tools/testing/selftests/kvm/s390x/ucontrol_test.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-)
diff --git a/tools/testing/selftests/kvm/s390x/ucontrol_test.c b/tools/testing/selftests/kvm/s390x/ucontrol_test.c index ae077bf838c8..db8776269373 100644 --- a/tools/testing/selftests/kvm/s390x/ucontrol_test.c +++ b/tools/testing/selftests/kvm/s390x/ucontrol_test.c @@ -369,7 +369,7 @@ static bool uc_handle_insn_ic(FIXTURE_DATA(uc_kvm) *self) * * fail on codes not expected in the test cases * Returns if interception is handled / execution can be continued */ -static bool uc_handle_sieic(FIXTURE_DATA(uc_kvm) * self) +static bool uc_handle_sieic(FIXTURE_DATA(uc_kvm) *self) { struct kvm_s390_sie_block *sie_block = self->sie_block; struct kvm_run *run = self->run; @@ -397,7 +397,7 @@ static bool uc_handle_sieic(FIXTURE_DATA(uc_kvm) * self) }
/* verify VM state on exit */ -static bool uc_handle_exit(FIXTURE_DATA(uc_kvm) * self) +static bool uc_handle_exit(FIXTURE_DATA(uc_kvm) *self) { struct kvm_run *run = self->run;
@@ -417,7 +417,7 @@ static bool uc_handle_exit(FIXTURE_DATA(uc_kvm) * self) }
/* run the VM until interrupted */ -static int uc_run_once(FIXTURE_DATA(uc_kvm) * self) +static int uc_run_once(FIXTURE_DATA(uc_kvm) *self) { int rc;
@@ -428,7 +428,7 @@ static int uc_run_once(FIXTURE_DATA(uc_kvm) * self) return rc; }
-static void uc_assert_diag44(FIXTURE_DATA(uc_kvm) * self) +static void uc_assert_diag44(FIXTURE_DATA(uc_kvm) *self) { struct kvm_s390_sie_block *sie_block = self->sie_block;
The length of the interrupt parameters (IP) are: a: 2 bytes b: 4 bytes
Signed-off-by: Christoph Schlameuss schlameuss@linux.ibm.com --- tools/testing/selftests/kvm/s390x/ucontrol_test.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/tools/testing/selftests/kvm/s390x/ucontrol_test.c b/tools/testing/selftests/kvm/s390x/ucontrol_test.c index db8776269373..e69e22504428 100644 --- a/tools/testing/selftests/kvm/s390x/ucontrol_test.c +++ b/tools/testing/selftests/kvm/s390x/ucontrol_test.c @@ -375,7 +375,7 @@ static bool uc_handle_sieic(FIXTURE_DATA(uc_kvm) *self) struct kvm_run *run = self->run;
/* check SIE interception code */ - pr_info("sieic: 0x%.2x 0x%.4x 0x%.4x\n", + pr_info("sieic: 0x%.2x 0x%.4x 0x%.8x\n", run->s390_sieic.icptcode, run->s390_sieic.ipa, run->s390_sieic.ipb);
linux-kselftest-mirror@lists.linaro.org
-
Christoph Schlameuss -
Janosch Frank