From 0d4d52361b6c29bf771acd4fa461f06d78fb2fac Mon Sep 17 00:00:00 2001 From: Niklas Schnelle Date: Tue, 3 Jan 2023 15:11:07 +0100 Subject: s390/debug: add _ASM_S390_ prefix to header guard Using DEBUG_H without a prefix is very generic and inconsistent with other header guards in arch/s390/include/asm. In fact it collides with the same name in the ath9k wireless driver though that depends on !S390 via disabled wireless support. Let's just use a consistent header guard name and prevent possible future trouble. Signed-off-by: Niklas Schnelle Signed-off-by: Heiko Carstens --- arch/s390/include/asm/debug.h | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'arch/s390') diff --git a/arch/s390/include/asm/debug.h b/arch/s390/include/asm/debug.h index 77f24262c25c..ac665b9670c5 100644 --- a/arch/s390/include/asm/debug.h +++ b/arch/s390/include/asm/debug.h @@ -4,8 +4,8 @@ * * Copyright IBM Corp. 1999, 2020 */ -#ifndef DEBUG_H -#define DEBUG_H +#ifndef _ASM_S390_DEBUG_H +#define _ASM_S390_DEBUG_H #include #include @@ -487,4 +487,4 @@ void debug_register_static(debug_info_t *id, int pages_per_area, int nr_areas); #endif /* MODULE */ -#endif /* DEBUG_H */ +#endif /* _ASM_S390_DEBUG_H */ -- cgit v1.2.3 From 45d619bdaf799196d702a9ae464b07066d6db2f9 Mon Sep 17 00:00:00 2001 From: Alexander Gordeev Date: Wed, 7 Dec 2022 17:15:19 +0100 Subject: s390: expicitly align _edata and _end symbols on page boundary Symbols _edata and _end in the linker script are the only unaligned expicitly on page boundary. Although _end is aligned implicitly by BSS_SECTION macro that is still inconsistent and could lead to a bug if a tool or function would assume that _edata is as aligned as others. For example, vmem_map_init() function does not align symbols _etext, _einittext etc. Should these symbols be unaligned as well, the size of ranges to update were short on one page. Instead of fixing every occurrence of this kind in the code and external tools just force the alignment on these two symbols. Reviewed-by: Heiko Carstens Signed-off-by: Alexander Gordeev Signed-off-by: Heiko Carstens --- arch/s390/kernel/vmlinux.lds.S | 2 ++ 1 file changed, 2 insertions(+) (limited to 'arch/s390') diff --git a/arch/s390/kernel/vmlinux.lds.S b/arch/s390/kernel/vmlinux.lds.S index 5ea3830af0cc..f81d96710595 100644 --- a/arch/s390/kernel/vmlinux.lds.S +++ b/arch/s390/kernel/vmlinux.lds.S @@ -79,6 +79,7 @@ SECTIONS _end_amode31_refs = .; } + . = ALIGN(PAGE_SIZE); _edata = .; /* End of data section */ /* will be freed after init */ @@ -193,6 +194,7 @@ SECTIONS BSS_SECTION(PAGE_SIZE, 4 * PAGE_SIZE, PAGE_SIZE) + . = ALIGN(PAGE_SIZE); _end = . ; /* -- cgit v1.2.3 From a494398bde273143c2352dd373cad8211f7d94b2 Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Thu, 5 Jan 2023 12:13:06 +0900 Subject: s390: define RUNTIME_DISCARD_EXIT to fix link error with GNU ld < 2.36 Nathan Chancellor reports that the s390 vmlinux fails to link with GNU ld < 2.36 since commit 99cb0d917ffa ("arch: fix broken BuildID for arm64 and riscv"). It happens for defconfig, or more specifically for CONFIG_EXPOLINE=y. $ s390x-linux-gnu-ld --version | head -n1 GNU ld (GNU Binutils for Debian) 2.35.2 $ make -s ARCH=s390 CROSS_COMPILE=s390x-linux-gnu- allnoconfig $ ./scripts/config -e CONFIG_EXPOLINE $ make -s ARCH=s390 CROSS_COMPILE=s390x-linux-gnu- olddefconfig $ make -s ARCH=s390 CROSS_COMPILE=s390x-linux-gnu- `.exit.text' referenced in section `.s390_return_reg' of drivers/base/dd.o: defined in discarded section `.exit.text' of drivers/base/dd.o make[1]: *** [scripts/Makefile.vmlinux:34: vmlinux] Error 1 make: *** [Makefile:1252: vmlinux] Error 2 arch/s390/kernel/vmlinux.lds.S wants to keep EXIT_TEXT: .exit.text : { EXIT_TEXT } But, at the same time, EXIT_TEXT is thrown away by DISCARD because s390 does not define RUNTIME_DISCARD_EXIT. I still do not understand why the latter wins after 99cb0d917ffa, but defining RUNTIME_DISCARD_EXIT seems correct because the comment line in arch/s390/kernel/vmlinux.lds.S says: /* * .exit.text is discarded at runtime, not link time, * to deal with references from __bug_table */ Nathan also found that binutils commit 21401fc7bf67 ("Duplicate output sections in scripts") cured this issue, so we cannot reproduce it with binutils 2.36+, but it is better to not rely on it. Fixes: 99cb0d917ffa ("arch: fix broken BuildID for arm64 and riscv") Link: https://lore.kernel.org/all/Y7Jal56f6UBh1abE@dev-arch.thelio-3990X/ Reported-by: Nathan Chancellor Signed-off-by: Masahiro Yamada Link: https://lore.kernel.org/r/20230105031306.1455409-1-masahiroy@kernel.org Signed-off-by: Heiko Carstens --- arch/s390/kernel/vmlinux.lds.S | 2 ++ 1 file changed, 2 insertions(+) (limited to 'arch/s390') diff --git a/arch/s390/kernel/vmlinux.lds.S b/arch/s390/kernel/vmlinux.lds.S index f81d96710595..cbf9c1b0beda 100644 --- a/arch/s390/kernel/vmlinux.lds.S +++ b/arch/s390/kernel/vmlinux.lds.S @@ -17,6 +17,8 @@ /* Handle ro_after_init data on our own. */ #define RO_AFTER_INIT_DATA +#define RUNTIME_DISCARD_EXIT + #define EMITS_PT_NOTE #include -- cgit v1.2.3 From f993d24a948d22710148dae2c48b8a87155f6cb9 Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Sat, 7 Jan 2023 01:10:23 +0900 Subject: s390: fix -Wundef warning for CONFIG_KERNEL_ZSTD Since commit 80b6093b55e3 ("kbuild: add -Wundef to KBUILD_CPPFLAGS for W=1 builds"), building with W=1 detects misuse of #(el)if. $ make W=1 ARCH=s390 CROSS_COMPILE=s390x-linux-gnu- [snip] arch/s390/boot/decompressor.c:28:7: warning: "CONFIG_KERNEL_ZSTD" is not defined, evaluates to 0 [-Wundef] 28 | #elif CONFIG_KERNEL_ZSTD | ^~~~~~~~~~~~~~~~~~ This issue has been hidden because arch/s390/boot/Makefile overwrites KBUILD_CFLAGS, dropping -Wundef. CONFIG_KERNEL_ZSTD is a bool option. #elif defined() should be used. The line #ifdef CONFIG_KERNEL_BZIP2 is fine, but I changed it for consistency. Signed-off-by: Masahiro Yamada Link: https://lore.kernel.org/r/20230106161024.2373602-1-masahiroy@kernel.org Signed-off-by: Heiko Carstens --- arch/s390/boot/decompressor.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'arch/s390') diff --git a/arch/s390/boot/decompressor.c b/arch/s390/boot/decompressor.c index e27c2140d620..8dcd7af2911a 100644 --- a/arch/s390/boot/decompressor.c +++ b/arch/s390/boot/decompressor.c @@ -23,9 +23,9 @@ #define memmove memmove #define memzero(s, n) memset((s), 0, (n)) -#ifdef CONFIG_KERNEL_BZIP2 +#if defined(CONFIG_KERNEL_BZIP2) #define BOOT_HEAP_SIZE 0x400000 -#elif CONFIG_KERNEL_ZSTD +#elif defined(CONFIG_KERNEL_ZSTD) #define BOOT_HEAP_SIZE 0x30000 #else #define BOOT_HEAP_SIZE 0x10000 -- cgit v1.2.3 From c2337a40e04dde1692b5b0a46ecc59f89aaba8a1 Mon Sep 17 00:00:00 2001 From: Alexander Egorenkov Date: Mon, 14 Nov 2022 11:40:08 +0100 Subject: s390/kexec: fix ipl report address for kdump This commit addresses the following erroneous situation with file-based kdump executed on a system with a valid IPL report. On s390, a kdump kernel, its initrd and IPL report if present are loaded into a special and reserved on boot memory region - crashkernel. When a system crashes and kdump was activated before, the purgatory code is entered first which swaps the crashkernel and [0 - crashkernel size] memory regions. Only after that the kdump kernel is entered. For this reason, the pointer to an IPL report in lowcore must point to the IPL report after the swap and not to the address of the IPL report that was located in crashkernel memory region before the swap. Failing to do so, makes the kdump's decompressor try to read memory from the crashkernel memory region which already contains the production's kernel memory. The situation described above caused spontaneous kdump failures/hangs on systems where the Secure IPL is activated because on such systems an IPL report is always present. In that case kdump's decompressor tried to parse an IPL report which frequently lead to illegal memory accesses because an IPL report contains addresses to various data. Cc: Fixes: 99feaa717e55 ("s390/kexec_file: Create ipl report and pass to next kernel") Reviewed-by: Vasily Gorbik Signed-off-by: Alexander Egorenkov Signed-off-by: Heiko Carstens --- arch/s390/kernel/machine_kexec_file.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) (limited to 'arch/s390') diff --git a/arch/s390/kernel/machine_kexec_file.c b/arch/s390/kernel/machine_kexec_file.c index fc6d5f58debe..2df94d32140c 100644 --- a/arch/s390/kernel/machine_kexec_file.c +++ b/arch/s390/kernel/machine_kexec_file.c @@ -187,8 +187,6 @@ static int kexec_file_add_ipl_report(struct kimage *image, data->memsz = ALIGN(data->memsz, PAGE_SIZE); buf.mem = data->memsz; - if (image->type == KEXEC_TYPE_CRASH) - buf.mem += crashk_res.start; ptr = (void *)ipl_cert_list_addr; end = ptr + ipl_cert_list_size; @@ -225,6 +223,9 @@ static int kexec_file_add_ipl_report(struct kimage *image, data->kernel_buf + offsetof(struct lowcore, ipl_parmblock_ptr); *lc_ipl_parmblock_ptr = (__u32)buf.mem; + if (image->type == KEXEC_TYPE_CRASH) + buf.mem += crashk_res.start; + ret = kexec_add_buffer(&buf); out: return ret; -- cgit v1.2.3 From 82d3edb50a11bf3c5ef63294d5358ba230181413 Mon Sep 17 00:00:00 2001 From: Heiko Carstens Date: Thu, 5 Jan 2023 15:44:20 +0100 Subject: s390/cpum_sf: add READ_ONCE() semantics to compare and swap loops The current cmpxchg_double() loops within the perf hw sampling code do not have READ_ONCE() semantics to read the old value from memory. This allows the compiler to generate code which reads the "old" value several times from memory, which again allows for inconsistencies. For example: /* Reset trailer (using compare-double-and-swap) */ do { te_flags = te->flags & ~SDB_TE_BUFFER_FULL_MASK; te_flags |= SDB_TE_ALERT_REQ_MASK; } while (!cmpxchg_double(&te->flags, &te->overflow, te->flags, te->overflow, te_flags, 0ULL)); The compiler could generate code where te->flags used within the cmpxchg_double() call may be refetched from memory and which is not necessarily identical to the previous read version which was used to generate te_flags. Which in turn means that an incorrect update could happen. Fix this by adding READ_ONCE() semantics to all cmpxchg_double() loops. Given that READ_ONCE() cannot generate code on s390 which atomically reads 16 bytes, use a private compare-and-swap-double implementation to achieve that. Also replace cmpxchg_double() with the private implementation to be able to re-use the old value within the loops. As a side effect this converts the whole code to only use bit fields to read and modify bits within the hws trailer header. Reported-by: Alexander Gordeev Acked-by: Alexander Gordeev Acked-by: Hendrik Brueckner Reviewed-by: Thomas Richter Cc: Link: https://lore.kernel.org/linux-s390/Y71QJBhNTIatvxUT@osiris/T/#ma14e2a5f7aa8ed4b94b6f9576799b3ad9c60f333 Signed-off-by: Heiko Carstens --- arch/s390/include/asm/cpu_mf.h | 31 ++++++------ arch/s390/kernel/perf_cpum_sf.c | 101 ++++++++++++++++++++++++---------------- 2 files changed, 77 insertions(+), 55 deletions(-) (limited to 'arch/s390') diff --git a/arch/s390/include/asm/cpu_mf.h b/arch/s390/include/asm/cpu_mf.h index feaba12dbecb..efa103b52a1a 100644 --- a/arch/s390/include/asm/cpu_mf.h +++ b/arch/s390/include/asm/cpu_mf.h @@ -131,19 +131,21 @@ struct hws_combined_entry { struct hws_diag_entry diag; /* Diagnostic-sampling data entry */ } __packed; -struct hws_trailer_entry { - union { - struct { - unsigned int f:1; /* 0 - Block Full Indicator */ - unsigned int a:1; /* 1 - Alert request control */ - unsigned int t:1; /* 2 - Timestamp format */ - unsigned int :29; /* 3 - 31: Reserved */ - unsigned int bsdes:16; /* 32-47: size of basic SDE */ - unsigned int dsdes:16; /* 48-63: size of diagnostic SDE */ - }; - unsigned long long flags; /* 0 - 63: All indicators */ +union hws_trailer_header { + struct { + unsigned int f:1; /* 0 - Block Full Indicator */ + unsigned int a:1; /* 1 - Alert request control */ + unsigned int t:1; /* 2 - Timestamp format */ + unsigned int :29; /* 3 - 31: Reserved */ + unsigned int bsdes:16; /* 32-47: size of basic SDE */ + unsigned int dsdes:16; /* 48-63: size of diagnostic SDE */ + unsigned long long overflow; /* 64 - Overflow Count */ }; - unsigned long long overflow; /* 64 - sample Overflow count */ + __uint128_t val; +}; + +struct hws_trailer_entry { + union hws_trailer_header header; /* 0 - 15 Flags + Overflow Count */ unsigned char timestamp[16]; /* 16 - 31 timestamp */ unsigned long long reserved1; /* 32 -Reserved */ unsigned long long reserved2; /* */ @@ -290,14 +292,11 @@ static inline unsigned long sample_rate_to_freq(struct hws_qsi_info_block *qsi, return USEC_PER_SEC * qsi->cpu_speed / rate; } -#define SDB_TE_ALERT_REQ_MASK 0x4000000000000000UL -#define SDB_TE_BUFFER_FULL_MASK 0x8000000000000000UL - /* Return TOD timestamp contained in an trailer entry */ static inline unsigned long long trailer_timestamp(struct hws_trailer_entry *te) { /* TOD in STCKE format */ - if (te->t) + if (te->header.t) return *((unsigned long long *) &te->timestamp[1]); /* TOD in STCK format */ diff --git a/arch/s390/kernel/perf_cpum_sf.c b/arch/s390/kernel/perf_cpum_sf.c index 332a49965130..ce886a03545a 100644 --- a/arch/s390/kernel/perf_cpum_sf.c +++ b/arch/s390/kernel/perf_cpum_sf.c @@ -163,14 +163,15 @@ static void free_sampling_buffer(struct sf_buffer *sfb) static int alloc_sample_data_block(unsigned long *sdbt, gfp_t gfp_flags) { - unsigned long sdb, *trailer; + struct hws_trailer_entry *te; + unsigned long sdb; /* Allocate and initialize sample-data-block */ sdb = get_zeroed_page(gfp_flags); if (!sdb) return -ENOMEM; - trailer = trailer_entry_ptr(sdb); - *trailer = SDB_TE_ALERT_REQ_MASK; + te = (struct hws_trailer_entry *)trailer_entry_ptr(sdb); + te->header.a = 1; /* Link SDB into the sample-data-block-table */ *sdbt = sdb; @@ -1206,7 +1207,7 @@ static void hw_collect_samples(struct perf_event *event, unsigned long *sdbt, "%s: Found unknown" " sampling data entry: te->f %i" " basic.def %#4x (%p)\n", __func__, - te->f, sample->def, sample); + te->header.f, sample->def, sample); /* Sample slot is not yet written or other record. * * This condition can occur if the buffer was reused @@ -1217,7 +1218,7 @@ static void hw_collect_samples(struct perf_event *event, unsigned long *sdbt, * that are not full. Stop processing if the first * invalid format was detected. */ - if (!te->f) + if (!te->header.f) break; } @@ -1227,6 +1228,16 @@ static void hw_collect_samples(struct perf_event *event, unsigned long *sdbt, } } +static inline __uint128_t __cdsg(__uint128_t *ptr, __uint128_t old, __uint128_t new) +{ + asm volatile( + " cdsg %[old],%[new],%[ptr]\n" + : [old] "+d" (old), [ptr] "+QS" (*ptr) + : [new] "d" (new) + : "memory", "cc"); + return old; +} + /* hw_perf_event_update() - Process sampling buffer * @event: The perf event * @flush_all: Flag to also flush partially filled sample-data-blocks @@ -1243,10 +1254,11 @@ static void hw_collect_samples(struct perf_event *event, unsigned long *sdbt, */ static void hw_perf_event_update(struct perf_event *event, int flush_all) { + unsigned long long event_overflow, sampl_overflow, num_sdb; + union hws_trailer_header old, prev, new; struct hw_perf_event *hwc = &event->hw; struct hws_trailer_entry *te; unsigned long *sdbt; - unsigned long long event_overflow, sampl_overflow, num_sdb, te_flags; int done; /* @@ -1266,25 +1278,25 @@ static void hw_perf_event_update(struct perf_event *event, int flush_all) te = (struct hws_trailer_entry *) trailer_entry_ptr(*sdbt); /* Leave loop if no more work to do (block full indicator) */ - if (!te->f) { + if (!te->header.f) { done = 1; if (!flush_all) break; } /* Check the sample overflow count */ - if (te->overflow) + if (te->header.overflow) /* Account sample overflows and, if a particular limit * is reached, extend the sampling buffer. * For details, see sfb_account_overflows(). */ - sampl_overflow += te->overflow; + sampl_overflow += te->header.overflow; /* Timestamps are valid for full sample-data-blocks only */ debug_sprintf_event(sfdbg, 6, "%s: sdbt %#lx " "overflow %llu timestamp %#llx\n", - __func__, (unsigned long)sdbt, te->overflow, - (te->f) ? trailer_timestamp(te) : 0ULL); + __func__, (unsigned long)sdbt, te->header.overflow, + (te->header.f) ? trailer_timestamp(te) : 0ULL); /* Collect all samples from a single sample-data-block and * flag if an (perf) event overflow happened. If so, the PMU @@ -1294,12 +1306,16 @@ static void hw_perf_event_update(struct perf_event *event, int flush_all) num_sdb++; /* Reset trailer (using compare-double-and-swap) */ + /* READ_ONCE() 16 byte header */ + prev.val = __cdsg(&te->header.val, 0, 0); do { - te_flags = te->flags & ~SDB_TE_BUFFER_FULL_MASK; - te_flags |= SDB_TE_ALERT_REQ_MASK; - } while (!cmpxchg_double(&te->flags, &te->overflow, - te->flags, te->overflow, - te_flags, 0ULL)); + old.val = prev.val; + new.val = prev.val; + new.f = 0; + new.a = 1; + new.overflow = 0; + prev.val = __cdsg(&te->header.val, old.val, new.val); + } while (prev.val != old.val); /* Advance to next sample-data-block */ sdbt++; @@ -1384,7 +1400,7 @@ static void aux_output_end(struct perf_output_handle *handle) range_scan = AUX_SDB_NUM_ALERT(aux); for (i = 0, idx = aux->head; i < range_scan; i++, idx++) { te = aux_sdb_trailer(aux, idx); - if (!(te->flags & SDB_TE_BUFFER_FULL_MASK)) + if (!te->header.f) break; } /* i is num of SDBs which are full */ @@ -1392,7 +1408,7 @@ static void aux_output_end(struct perf_output_handle *handle) /* Remove alert indicators in the buffer */ te = aux_sdb_trailer(aux, aux->alert_mark); - te->flags &= ~SDB_TE_ALERT_REQ_MASK; + te->header.a = 0; debug_sprintf_event(sfdbg, 6, "%s: SDBs %ld range %ld head %ld\n", __func__, i, range_scan, aux->head); @@ -1437,9 +1453,9 @@ static int aux_output_begin(struct perf_output_handle *handle, idx = aux->empty_mark + 1; for (i = 0; i < range_scan; i++, idx++) { te = aux_sdb_trailer(aux, idx); - te->flags &= ~(SDB_TE_BUFFER_FULL_MASK | - SDB_TE_ALERT_REQ_MASK); - te->overflow = 0; + te->header.f = 0; + te->header.a = 0; + te->header.overflow = 0; } /* Save the position of empty SDBs */ aux->empty_mark = aux->head + range - 1; @@ -1448,7 +1464,7 @@ static int aux_output_begin(struct perf_output_handle *handle, /* Set alert indicator */ aux->alert_mark = aux->head + range/2 - 1; te = aux_sdb_trailer(aux, aux->alert_mark); - te->flags = te->flags | SDB_TE_ALERT_REQ_MASK; + te->header.a = 1; /* Reset hardware buffer head */ head = AUX_SDB_INDEX(aux, aux->head); @@ -1475,14 +1491,17 @@ static int aux_output_begin(struct perf_output_handle *handle, static bool aux_set_alert(struct aux_buffer *aux, unsigned long alert_index, unsigned long long *overflow) { - unsigned long long orig_overflow, orig_flags, new_flags; + union hws_trailer_header old, prev, new; struct hws_trailer_entry *te; te = aux_sdb_trailer(aux, alert_index); + /* READ_ONCE() 16 byte header */ + prev.val = __cdsg(&te->header.val, 0, 0); do { - orig_flags = te->flags; - *overflow = orig_overflow = te->overflow; - if (orig_flags & SDB_TE_BUFFER_FULL_MASK) { + old.val = prev.val; + new.val = prev.val; + *overflow = old.overflow; + if (old.f) { /* * SDB is already set by hardware. * Abort and try to set somewhere @@ -1490,10 +1509,10 @@ static bool aux_set_alert(struct aux_buffer *aux, unsigned long alert_index, */ return false; } - new_flags = orig_flags | SDB_TE_ALERT_REQ_MASK; - } while (!cmpxchg_double(&te->flags, &te->overflow, - orig_flags, orig_overflow, - new_flags, 0ULL)); + new.a = 1; + new.overflow = 0; + prev.val = __cdsg(&te->header.val, old.val, new.val); + } while (prev.val != old.val); return true; } @@ -1522,8 +1541,9 @@ static bool aux_set_alert(struct aux_buffer *aux, unsigned long alert_index, static bool aux_reset_buffer(struct aux_buffer *aux, unsigned long range, unsigned long long *overflow) { - unsigned long long orig_overflow, orig_flags, new_flags; unsigned long i, range_scan, idx, idx_old; + union hws_trailer_header old, prev, new; + unsigned long long orig_overflow; struct hws_trailer_entry *te; debug_sprintf_event(sfdbg, 6, "%s: range %ld head %ld alert %ld " @@ -1554,17 +1574,20 @@ static bool aux_reset_buffer(struct aux_buffer *aux, unsigned long range, idx_old = idx = aux->empty_mark + 1; for (i = 0; i < range_scan; i++, idx++) { te = aux_sdb_trailer(aux, idx); + /* READ_ONCE() 16 byte header */ + prev.val = __cdsg(&te->header.val, 0, 0); do { - orig_flags = te->flags; - orig_overflow = te->overflow; - new_flags = orig_flags & ~SDB_TE_BUFFER_FULL_MASK; + old.val = prev.val; + new.val = prev.val; + orig_overflow = old.overflow; + new.f = 0; + new.overflow = 0; if (idx == aux->alert_mark) - new_flags |= SDB_TE_ALERT_REQ_MASK; + new.a = 1; else - new_flags &= ~SDB_TE_ALERT_REQ_MASK; - } while (!cmpxchg_double(&te->flags, &te->overflow, - orig_flags, orig_overflow, - new_flags, 0ULL)); + new.a = 0; + prev.val = __cdsg(&te->header.val, old.val, new.val); + } while (prev.val != old.val); *overflow += orig_overflow; } -- cgit v1.2.3 From e3f360db08d55a14112bd27454e616a24296a8b0 Mon Sep 17 00:00:00 2001 From: Heiko Carstens Date: Mon, 9 Jan 2023 11:51:20 +0100 Subject: s390/percpu: add READ_ONCE() to arch_this_cpu_to_op_simple() Make sure that *ptr__ within arch_this_cpu_to_op_simple() is only dereferenced once by using READ_ONCE(). Otherwise the compiler could generate incorrect code. Cc: Reviewed-by: Alexander Gordeev Signed-off-by: Heiko Carstens --- arch/s390/include/asm/percpu.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'arch/s390') diff --git a/arch/s390/include/asm/percpu.h b/arch/s390/include/asm/percpu.h index cb5fc0690435..081837b391e3 100644 --- a/arch/s390/include/asm/percpu.h +++ b/arch/s390/include/asm/percpu.h @@ -31,7 +31,7 @@ pcp_op_T__ *ptr__; \ preempt_disable_notrace(); \ ptr__ = raw_cpu_ptr(&(pcp)); \ - prev__ = *ptr__; \ + prev__ = READ_ONCE(*ptr__); \ do { \ old__ = prev__; \ new__ = old__ op (val); \ -- cgit v1.2.3 From 42400d99e9f0728c17240edb9645637ead40f6b9 Mon Sep 17 00:00:00 2001 From: Heiko Carstens Date: Mon, 9 Jan 2023 15:54:56 +0100 Subject: KVM: s390: interrupt: use READ_ONCE() before cmpxchg() Use READ_ONCE() before cmpxchg() to prevent that the compiler generates code that fetches the to be compared old value several times from memory. Reviewed-by: Christian Borntraeger Acked-by: Christian Borntraeger Reviewed-by: Claudio Imbrenda Link: https://lore.kernel.org/r/20230109145456.2895385-1-hca@linux.ibm.com Signed-off-by: Heiko Carstens --- arch/s390/kvm/interrupt.c | 12 ++++++++---- 1 file changed, 8 insertions(+), 4 deletions(-) (limited to 'arch/s390') diff --git a/arch/s390/kvm/interrupt.c b/arch/s390/kvm/interrupt.c index 1dae78deddf2..ab26aa53ee37 100644 --- a/arch/s390/kvm/interrupt.c +++ b/arch/s390/kvm/interrupt.c @@ -83,8 +83,9 @@ static int sca_inject_ext_call(struct kvm_vcpu *vcpu, int src_id) struct esca_block *sca = vcpu->kvm->arch.sca; union esca_sigp_ctrl *sigp_ctrl = &(sca->cpu[vcpu->vcpu_id].sigp_ctrl); - union esca_sigp_ctrl new_val = {0}, old_val = *sigp_ctrl; + union esca_sigp_ctrl new_val = {0}, old_val; + old_val = READ_ONCE(*sigp_ctrl); new_val.scn = src_id; new_val.c = 1; old_val.c = 0; @@ -95,8 +96,9 @@ static int sca_inject_ext_call(struct kvm_vcpu *vcpu, int src_id) struct bsca_block *sca = vcpu->kvm->arch.sca; union bsca_sigp_ctrl *sigp_ctrl = &(sca->cpu[vcpu->vcpu_id].sigp_ctrl); - union bsca_sigp_ctrl new_val = {0}, old_val = *sigp_ctrl; + union bsca_sigp_ctrl new_val = {0}, old_val; + old_val = READ_ONCE(*sigp_ctrl); new_val.scn = src_id; new_val.c = 1; old_val.c = 0; @@ -126,16 +128,18 @@ static void sca_clear_ext_call(struct kvm_vcpu *vcpu) struct esca_block *sca = vcpu->kvm->arch.sca; union esca_sigp_ctrl *sigp_ctrl = &(sca->cpu[vcpu->vcpu_id].sigp_ctrl); - union esca_sigp_ctrl old = *sigp_ctrl; + union esca_sigp_ctrl old; + old = READ_ONCE(*sigp_ctrl); expect = old.value; rc = cmpxchg(&sigp_ctrl->value, old.value, 0); } else { struct bsca_block *sca = vcpu->kvm->arch.sca; union bsca_sigp_ctrl *sigp_ctrl = &(sca->cpu[vcpu->vcpu_id].sigp_ctrl); - union bsca_sigp_ctrl old = *sigp_ctrl; + union bsca_sigp_ctrl old; + old = READ_ONCE(*sigp_ctrl); expect = old.value; rc = cmpxchg(&sigp_ctrl->value, old.value, 0); } -- cgit v1.2.3 From 1ecf7bd9c267ab85aff3c4a17fe56bc9754a13be Mon Sep 17 00:00:00 2001 From: Heiko Carstens Date: Wed, 11 Jan 2023 15:04:47 +0100 Subject: s390: update defconfigs Signed-off-by: Heiko Carstens --- arch/s390/configs/debug_defconfig | 7 ++++--- arch/s390/configs/defconfig | 6 ++++-- arch/s390/configs/zfcpdump_defconfig | 2 +- 3 files changed, 9 insertions(+), 6 deletions(-) (limited to 'arch/s390') diff --git a/arch/s390/configs/debug_defconfig b/arch/s390/configs/debug_defconfig index a7b4e1d82758..74b35ec2ad28 100644 --- a/arch/s390/configs/debug_defconfig +++ b/arch/s390/configs/debug_defconfig @@ -190,7 +190,6 @@ CONFIG_NFT_CT=m CONFIG_NFT_LOG=m CONFIG_NFT_LIMIT=m CONFIG_NFT_NAT=m -CONFIG_NFT_OBJREF=m CONFIG_NFT_REJECT=m CONFIG_NFT_COMPAT=m CONFIG_NFT_HASH=m @@ -569,6 +568,7 @@ CONFIG_INPUT_EVDEV=y # CONFIG_INPUT_MOUSE is not set # CONFIG_SERIO is not set CONFIG_LEGACY_PTY_COUNT=0 +# CONFIG_LEGACY_TIOCSTI is not set CONFIG_VIRTIO_CONSOLE=m CONFIG_HW_RANDOM_VIRTIO=m CONFIG_HANGCHECK_TIMER=m @@ -660,6 +660,7 @@ CONFIG_CONFIGFS_FS=m CONFIG_ECRYPT_FS=m CONFIG_CRAMFS=m CONFIG_SQUASHFS=m +CONFIG_SQUASHFS_CHOICE_DECOMP_BY_MOUNT=y CONFIG_SQUASHFS_XATTR=y CONFIG_SQUASHFS_LZ4=y CONFIG_SQUASHFS_LZO=y @@ -705,6 +706,7 @@ CONFIG_SECURITY_LOCKDOWN_LSM_EARLY=y CONFIG_SECURITY_LANDLOCK=y CONFIG_INTEGRITY_SIGNATURE=y CONFIG_INTEGRITY_ASYMMETRIC_KEYS=y +CONFIG_INTEGRITY_PLATFORM_KEYRING=y CONFIG_IMA=y CONFIG_IMA_DEFAULT_HASH_SHA256=y CONFIG_IMA_WRITE_POLICY=y @@ -781,6 +783,7 @@ CONFIG_ZCRYPT=m CONFIG_PKEY=m CONFIG_CRYPTO_PAES_S390=m CONFIG_CRYPTO_DEV_VIRTIO=m +CONFIG_SYSTEM_BLACKLIST_KEYRING=y CONFIG_CORDIC=m CONFIG_CRYPTO_LIB_CURVE25519=m CONFIG_CRYPTO_LIB_CHACHA20POLY1305=m @@ -848,7 +851,6 @@ CONFIG_PREEMPT_TRACER=y CONFIG_SCHED_TRACER=y CONFIG_FTRACE_SYSCALLS=y CONFIG_BLK_DEV_IO_TRACE=y -CONFIG_BPF_KPROBE_OVERRIDE=y CONFIG_HIST_TRIGGERS=y CONFIG_FTRACE_STARTUP_TEST=y # CONFIG_EVENT_TRACE_STARTUP_TEST is not set @@ -870,7 +872,6 @@ CONFIG_FAIL_MAKE_REQUEST=y CONFIG_FAIL_IO_TIMEOUT=y CONFIG_FAIL_FUTEX=y CONFIG_FAULT_INJECTION_DEBUG_FS=y -CONFIG_FAIL_FUNCTION=y CONFIG_FAULT_INJECTION_STACKTRACE_FILTER=y CONFIG_LKDTM=m CONFIG_TEST_MIN_HEAP=y diff --git a/arch/s390/configs/defconfig b/arch/s390/configs/defconfig index 2bc2d0fe5774..cec71268e3bc 100644 --- a/arch/s390/configs/defconfig +++ b/arch/s390/configs/defconfig @@ -181,7 +181,6 @@ CONFIG_NFT_CT=m CONFIG_NFT_LOG=m CONFIG_NFT_LIMIT=m CONFIG_NFT_NAT=m -CONFIG_NFT_OBJREF=m CONFIG_NFT_REJECT=m CONFIG_NFT_COMPAT=m CONFIG_NFT_HASH=m @@ -559,6 +558,7 @@ CONFIG_INPUT_EVDEV=y # CONFIG_INPUT_MOUSE is not set # CONFIG_SERIO is not set CONFIG_LEGACY_PTY_COUNT=0 +# CONFIG_LEGACY_TIOCSTI is not set CONFIG_VIRTIO_CONSOLE=m CONFIG_HW_RANDOM_VIRTIO=m CONFIG_HANGCHECK_TIMER=m @@ -645,6 +645,7 @@ CONFIG_CONFIGFS_FS=m CONFIG_ECRYPT_FS=m CONFIG_CRAMFS=m CONFIG_SQUASHFS=m +CONFIG_SQUASHFS_CHOICE_DECOMP_BY_MOUNT=y CONFIG_SQUASHFS_XATTR=y CONFIG_SQUASHFS_LZ4=y CONFIG_SQUASHFS_LZO=y @@ -688,6 +689,7 @@ CONFIG_SECURITY_LOCKDOWN_LSM_EARLY=y CONFIG_SECURITY_LANDLOCK=y CONFIG_INTEGRITY_SIGNATURE=y CONFIG_INTEGRITY_ASYMMETRIC_KEYS=y +CONFIG_INTEGRITY_PLATFORM_KEYRING=y CONFIG_IMA=y CONFIG_IMA_DEFAULT_HASH_SHA256=y CONFIG_IMA_WRITE_POLICY=y @@ -766,6 +768,7 @@ CONFIG_ZCRYPT=m CONFIG_PKEY=m CONFIG_CRYPTO_PAES_S390=m CONFIG_CRYPTO_DEV_VIRTIO=m +CONFIG_SYSTEM_BLACKLIST_KEYRING=y CONFIG_CORDIC=m CONFIG_PRIME_NUMBERS=m CONFIG_CRYPTO_LIB_CURVE25519=m @@ -798,7 +801,6 @@ CONFIG_STACK_TRACER=y CONFIG_SCHED_TRACER=y CONFIG_FTRACE_SYSCALLS=y CONFIG_BLK_DEV_IO_TRACE=y -CONFIG_BPF_KPROBE_OVERRIDE=y CONFIG_HIST_TRIGGERS=y CONFIG_SAMPLES=y CONFIG_SAMPLE_TRACE_PRINTK=m diff --git a/arch/s390/configs/zfcpdump_defconfig b/arch/s390/configs/zfcpdump_defconfig index ae14ab0b864d..a9c0c81d1de9 100644 --- a/arch/s390/configs/zfcpdump_defconfig +++ b/arch/s390/configs/zfcpdump_defconfig @@ -13,7 +13,6 @@ CONFIG_TUNE_ZEC12=y # CONFIG_COMPAT is not set CONFIG_NR_CPUS=2 CONFIG_HZ_100=y -# CONFIG_RELOCATABLE is not set # CONFIG_CHSC_SCH is not set # CONFIG_SCM_BUS is not set CONFIG_CRASH_DUMP=y @@ -50,6 +49,7 @@ CONFIG_ZFCP=y # CONFIG_INPUT_KEYBOARD is not set # CONFIG_INPUT_MOUSE is not set # CONFIG_SERIO is not set +# CONFIG_LEGACY_TIOCSTI is not set # CONFIG_HVC_IUCV is not set # CONFIG_HW_RANDOM_S390 is not set # CONFIG_HMC_DRV is not set -- cgit v1.2.3 From 41e1992665a2701fa025a8b76970c43b4148446f Mon Sep 17 00:00:00 2001 From: Heiko Carstens Date: Tue, 17 Jan 2023 19:00:59 +0100 Subject: s390: workaround invalid gcc-11 out of bounds read warning MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit GCC 11.1.0 and 11.2.0 generate a wrong warning when compiling the kernel e.g. with allmodconfig: arch/s390/kernel/setup.c: In function ‘setup_lowcore_dat_on’: ./include/linux/fortify-string.h:57:33: error: ‘__builtin_memcpy’ reading 128 bytes from a region of size 0 [-Werror=stringop-overread] ... arch/s390/kernel/setup.c:526:9: note: in expansion of macro ‘memcpy’ 526 | memcpy(abs_lc->cregs_save_area, S390_lowcore.cregs_save_area, | ^~~~~~ This could be addressed by using absolute_pointer() with the S390_lowcore macro, but this is not a good idea since this generates worse code for performance critical paths. Therefore simply use a for loop to copy the array in question and get rid of the warning. Reported-by: Geert Uytterhoeven Signed-off-by: Heiko Carstens --- arch/s390/kernel/setup.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) (limited to 'arch/s390') diff --git a/arch/s390/kernel/setup.c b/arch/s390/kernel/setup.c index 2b6091349daa..696c9e007a36 100644 --- a/arch/s390/kernel/setup.c +++ b/arch/s390/kernel/setup.c @@ -508,6 +508,7 @@ static void __init setup_lowcore_dat_on(void) { struct lowcore *abs_lc; unsigned long flags; + int i; __ctl_clear_bit(0, 28); S390_lowcore.external_new_psw.mask |= PSW_MASK_DAT; @@ -523,8 +524,8 @@ static void __init setup_lowcore_dat_on(void) abs_lc = get_abs_lowcore(&flags); abs_lc->restart_flags = RESTART_FLAG_CTLREGS; abs_lc->program_new_psw = S390_lowcore.program_new_psw; - memcpy(abs_lc->cregs_save_area, S390_lowcore.cregs_save_area, - sizeof(abs_lc->cregs_save_area)); + for (i = 0; i < 16; i++) + abs_lc->cregs_save_area[i] = S390_lowcore.cregs_save_area[i]; put_abs_lowcore(abs_lc, flags); } -- cgit v1.2.3 From 7ab41c2c08a32132ba8c14624910e2fe8ce4ba4b Mon Sep 17 00:00:00 2001 From: Vasily Gorbik Date: Sun, 29 Jan 2023 23:47:23 +0100 Subject: s390/decompressor: specify __decompress() buf len to avoid overflow Historically calls to __decompress() didn't specify "out_len" parameter on many architectures including s390, expecting that no writes beyond uncompressed kernel image are performed. This has changed since commit 2aa14b1ab2c4 ("zstd: import usptream v1.5.2") which includes zstd library commit 6a7ede3dfccb ("Reduce size of dctx by reutilizing dst buffer (#2751)"). Now zstd decompression code might store literal buffer in the unwritten portion of the destination buffer. Since "out_len" is not set, it is considered to be unlimited and hence free to use for optimization needs. On s390 this might corrupt initrd or ipl report which are often placed right after the decompressor buffer. Luckily the size of uncompressed kernel image is already known to the decompressor, so to avoid the problem simply specify it in the "out_len" parameter. Link: https://github.com/facebook/zstd/commit/6a7ede3dfccb Signed-off-by: Vasily Gorbik Tested-by: Alexander Egorenkov Link: https://lore.kernel.org/r/patch-1.thread-41c676.git-41c676c2d153.your-ad-here.call-01675030179-ext-9637@work.hours Signed-off-by: Heiko Carstens --- arch/s390/boot/decompressor.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'arch/s390') diff --git a/arch/s390/boot/decompressor.c b/arch/s390/boot/decompressor.c index 8dcd7af2911a..b519a1f045d8 100644 --- a/arch/s390/boot/decompressor.c +++ b/arch/s390/boot/decompressor.c @@ -80,6 +80,6 @@ void *decompress_kernel(void) void *output = (void *)decompress_offset; __decompress(_compressed_start, _compressed_end - _compressed_start, - NULL, NULL, output, 0, NULL, error); + NULL, NULL, output, vmlinux.image_size, NULL, error); return output; } -- cgit v1.2.3