From 2bd161a605f1f84a5fc8a4fe8410113a94f79355 Mon Sep 17 00:00:00 2001 From: "David S. Miller" Date: Fri, 27 Sep 2013 13:46:04 -0700 Subject: sparc64: Fix buggy strlcpy() conversion in ldom_reboot(). Commit 117a0c5fc9c2d06045bd217385b2b39ea426b5a6 ("sparc: kernel: using strlcpy() instead of strcpy()") added a bug to ldom_reboot in arch/sparc/kernel/ds.c - strcpy(full_boot_str + strlen("boot "), boot_command); + strlcpy(full_boot_str + strlen("boot "), boot_command, + sizeof(full_boot_str + strlen("boot "))); That last sizeof() expression evaluates to sizeof(size_t) which is not what was intended. Also even the corrected: sizeof(full_boot_str) + strlen("boot ") is not right as the destination buffer length is just plain "sizeof(full_boot_str)" and that's what the final argument should be. Signed-off-by: David S. Miller --- arch/sparc/kernel/ds.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'arch/sparc') diff --git a/arch/sparc/kernel/ds.c b/arch/sparc/kernel/ds.c index 62d6b153ffa2..4d9ac8406f32 100644 --- a/arch/sparc/kernel/ds.c +++ b/arch/sparc/kernel/ds.c @@ -851,7 +851,7 @@ void ldom_reboot(const char *boot_command) strcpy(full_boot_str, "boot "); strlcpy(full_boot_str + strlen("boot "), boot_command, - sizeof(full_boot_str + strlen("boot "))); + sizeof(full_boot_str)); len = strlen(full_boot_str); if (reboot_data_supported) { -- cgit v1.2.3 From 20928bd3f08afb036c096d9559d581926b895918 Mon Sep 17 00:00:00 2001 From: Kees Cook Date: Tue, 1 Oct 2013 22:13:34 -0700 Subject: sparc: fix ldom_reboot buffer overflow harder The length argument to strlcpy was still wrong. It could overflow the end of full_boot_str by 5 bytes. Instead of strcat and strlcpy, just use snprint. Reported-by: Brad Spengler Signed-off-by: Kees Cook Signed-off-by: David S. Miller --- arch/sparc/kernel/ds.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) (limited to 'arch/sparc') diff --git a/arch/sparc/kernel/ds.c b/arch/sparc/kernel/ds.c index 4d9ac8406f32..dff60abbea01 100644 --- a/arch/sparc/kernel/ds.c +++ b/arch/sparc/kernel/ds.c @@ -849,9 +849,8 @@ void ldom_reboot(const char *boot_command) if (boot_command && strlen(boot_command)) { unsigned long len; - strcpy(full_boot_str, "boot "); - strlcpy(full_boot_str + strlen("boot "), boot_command, - sizeof(full_boot_str)); + snprintf(full_boot_str, sizeof(full_boot_str), "boot %s", + boot_command); len = strlen(full_boot_str); if (reboot_data_supported) { -- cgit v1.2.3 From d2f09b1c17158fa870fb4f78babf1b307cd2685b Mon Sep 17 00:00:00 2001 From: Michael Opdenacker Date: Sat, 7 Sep 2013 09:38:09 +0200 Subject: sparc: remove deprecated IRQF_DISABLED This patch proposes to remove the IRQF_DISABLED flag from sparc architecture code. It's a NOOP since 2.6.35 and it will be removed one day. Signed-off-by: Michael Opdenacker Signed-off-by: David S. Miller --- arch/sparc/include/asm/floppy_64.h | 2 +- arch/sparc/kernel/ldc.c | 4 ++-- 2 files changed, 3 insertions(+), 3 deletions(-) (limited to 'arch/sparc') diff --git a/arch/sparc/include/asm/floppy_64.h b/arch/sparc/include/asm/floppy_64.h index e204f902e6c9..7c90c50c200d 100644 --- a/arch/sparc/include/asm/floppy_64.h +++ b/arch/sparc/include/asm/floppy_64.h @@ -254,7 +254,7 @@ static int sun_fd_request_irq(void) once = 1; error = request_irq(FLOPPY_IRQ, sparc_floppy_irq, - IRQF_DISABLED, "floppy", NULL); + 0, "floppy", NULL); return ((error == 0) ? 0 : -1); } diff --git a/arch/sparc/kernel/ldc.c b/arch/sparc/kernel/ldc.c index 54df554b82d9..e01d75d40329 100644 --- a/arch/sparc/kernel/ldc.c +++ b/arch/sparc/kernel/ldc.c @@ -1249,12 +1249,12 @@ int ldc_bind(struct ldc_channel *lp, const char *name) snprintf(lp->rx_irq_name, LDC_IRQ_NAME_MAX, "%s RX", name); snprintf(lp->tx_irq_name, LDC_IRQ_NAME_MAX, "%s TX", name); - err = request_irq(lp->cfg.rx_irq, ldc_rx, IRQF_DISABLED, + err = request_irq(lp->cfg.rx_irq, ldc_rx, 0, lp->rx_irq_name, lp); if (err) return err; - err = request_irq(lp->cfg.tx_irq, ldc_tx, IRQF_DISABLED, + err = request_irq(lp->cfg.tx_irq, ldc_tx, 0, lp->tx_irq_name, lp); if (err) { free_irq(lp->cfg.rx_irq, lp); -- cgit v1.2.3 From a988fb806d72d4e3a0edbeaece3f2f1172ce44b8 Mon Sep 17 00:00:00 2001 From: Thomas Petazzoni Date: Wed, 11 Sep 2013 12:32:05 +0200 Subject: sparc: fix MSI build failure on Sparc32 Commit ebd97be635 ('PCI: remove ARCH_SUPPORTS_MSI kconfig option') removes the ARCH_SUPPORTS_MSI Kconfig option that allowed architectures to indicate whether they support PCI MSI or not. Now, PCI MSI support can be compiled in on any architecture thanks to the use of weak functions thanks to 4287d824f265 ('PCI: use weak functions for MSI arch-specific functions'). So, architecture specific code is now responsible to ensure that its PCI MSI code builds in all cases, or be appropriately conditionally compiled. On Sparc, the MSI support is only provided for Sparc64, so the ARCH_SUPPORTS_MSI kconfig option was only selected for SPARC64, and not for the Sparc architecture as a whole. Therefore, removing ARCH_SUPPORTS_MSI broke Sparc32 configurations with CONFIG_PCI_MSI=y, because the Sparc-specific MSI code is not designed to be built on Sparc32. To solve this, this commit ensures that the Sparc MSI code is only built on Sparc64. This is done thanks to a new Kconfig Makefile helper option SPARC64_PCI_MSI, modeled after the existing SPARC64_PCI. The SPARC64_PCI_MSI option is an hidden option that is true when both Sparc64 PCI support is enabled and MSI is enabled. The arch/sparc/kernel/pci_msi.c file is now only built when SPARC64_PCI_MSI is true. Signed-off-by: Thomas Petazzoni Reported-by: Guenter Roeck Tested-by: Guenter Roeck Signed-off-by: David S. Miller --- arch/sparc/Kconfig | 7 ++++++- arch/sparc/kernel/Makefile | 3 ++- 2 files changed, 8 insertions(+), 2 deletions(-) (limited to 'arch/sparc') diff --git a/arch/sparc/Kconfig b/arch/sparc/Kconfig index 2137ad667438..78c4fdb91bc5 100644 --- a/arch/sparc/Kconfig +++ b/arch/sparc/Kconfig @@ -506,12 +506,17 @@ config SUN_OPENPROMFS Only choose N if you know in advance that you will not need to modify OpenPROM settings on the running system. -# Makefile helper +# Makefile helpers config SPARC64_PCI bool default y depends on SPARC64 && PCI +config SPARC64_PCI_MSI + bool + default y + depends on SPARC64_PCI && PCI_MSI + endmenu menu "Executable file formats" diff --git a/arch/sparc/kernel/Makefile b/arch/sparc/kernel/Makefile index d432fb20358e..d15cc1794b0e 100644 --- a/arch/sparc/kernel/Makefile +++ b/arch/sparc/kernel/Makefile @@ -1,3 +1,4 @@ + # # Makefile for the linux kernel. # @@ -99,7 +100,7 @@ obj-$(CONFIG_STACKTRACE) += stacktrace.o obj-$(CONFIG_SPARC64_PCI) += pci.o pci_common.o psycho_common.o obj-$(CONFIG_SPARC64_PCI) += pci_psycho.o pci_sabre.o pci_schizo.o obj-$(CONFIG_SPARC64_PCI) += pci_sun4v.o pci_sun4v_asm.o pci_fire.o -obj-$(CONFIG_PCI_MSI) += pci_msi.o +obj-$(CONFIG_SPARC64_PCI_MSI) += pci_msi.o obj-$(CONFIG_COMPAT) += sys32.o sys_sparc32.o signal32.o -- cgit v1.2.3 From d45ed4a4e33ae103053c0a53d280014e7101bb5c Mon Sep 17 00:00:00 2001 From: Alexei Starovoitov Date: Fri, 4 Oct 2013 00:14:06 -0700 Subject: net: fix unsafe set_memory_rw from softirq on x86 system with net.core.bpf_jit_enable = 1 sudo tcpdump -i eth1 'tcp port 22' causes the warning: [ 56.766097] Possible unsafe locking scenario: [ 56.766097] [ 56.780146] CPU0 [ 56.786807] ---- [ 56.793188] lock(&(&vb->lock)->rlock); [ 56.799593] [ 56.805889] lock(&(&vb->lock)->rlock); [ 56.812266] [ 56.812266] *** DEADLOCK *** [ 56.812266] [ 56.830670] 1 lock held by ksoftirqd/1/13: [ 56.836838] #0: (rcu_read_lock){.+.+..}, at: [] vm_unmap_aliases+0x8c/0x380 [ 56.849757] [ 56.849757] stack backtrace: [ 56.862194] CPU: 1 PID: 13 Comm: ksoftirqd/1 Not tainted 3.12.0-rc3+ #45 [ 56.868721] Hardware name: System manufacturer System Product Name/P8Z77 WS, BIOS 3007 07/26/2012 [ 56.882004] ffffffff821944c0 ffff88080bbdb8c8 ffffffff8175a145 0000000000000007 [ 56.895630] ffff88080bbd5f40 ffff88080bbdb928 ffffffff81755b14 0000000000000001 [ 56.909313] ffff880800000001 ffff880800000000 ffffffff8101178f 0000000000000001 [ 56.923006] Call Trace: [ 56.929532] [] dump_stack+0x55/0x76 [ 56.936067] [] print_usage_bug+0x1f7/0x208 [ 56.942445] [] ? save_stack_trace+0x2f/0x50 [ 56.948932] [] ? check_usage_backwards+0x150/0x150 [ 56.955470] [] mark_lock+0x282/0x2c0 [ 56.961945] [] __lock_acquire+0x45d/0x1d50 [ 56.968474] [] ? __lock_acquire+0x2de/0x1d50 [ 56.975140] [] ? cpumask_next_and+0x55/0x90 [ 56.981942] [] lock_acquire+0x92/0x1d0 [ 56.988745] [] ? vm_unmap_aliases+0x16a/0x380 [ 56.995619] [] _raw_spin_lock+0x41/0x50 [ 57.002493] [] ? vm_unmap_aliases+0x16a/0x380 [ 57.009447] [] vm_unmap_aliases+0x16a/0x380 [ 57.016477] [] ? vm_unmap_aliases+0x8c/0x380 [ 57.023607] [] change_page_attr_set_clr+0xc0/0x460 [ 57.030818] [] ? trace_hardirqs_on+0xd/0x10 [ 57.037896] [] ? kmem_cache_free+0xb0/0x2b0 [ 57.044789] [] ? free_object_rcu+0x93/0xa0 [ 57.051720] [] set_memory_rw+0x2f/0x40 [ 57.058727] [] bpf_jit_free+0x2c/0x40 [ 57.065577] [] sk_filter_release_rcu+0x1a/0x30 [ 57.072338] [] rcu_process_callbacks+0x202/0x7c0 [ 57.078962] [] __do_softirq+0xf7/0x3f0 [ 57.085373] [] run_ksoftirqd+0x35/0x70 cannot reuse jited filter memory, since it's readonly, so use original bpf insns memory to hold work_struct defer kfree of sk_filter until jit completed freeing tested on x86_64 and i386 Signed-off-by: Alexei Starovoitov Acked-by: Eric Dumazet Signed-off-by: David S. Miller --- arch/arm/net/bpf_jit_32.c | 1 + arch/powerpc/net/bpf_jit_comp.c | 1 + arch/s390/net/bpf_jit_comp.c | 4 +++- arch/sparc/net/bpf_jit_comp.c | 1 + arch/x86/net/bpf_jit_comp.c | 18 +++++++++++++----- include/linux/filter.h | 15 +++++++++++---- include/net/sock.h | 6 ++---- net/core/filter.c | 8 ++++---- 8 files changed, 36 insertions(+), 18 deletions(-) (limited to 'arch/sparc') diff --git a/arch/arm/net/bpf_jit_32.c b/arch/arm/net/bpf_jit_32.c index f50d223a0bd3..99b44e0e8d86 100644 --- a/arch/arm/net/bpf_jit_32.c +++ b/arch/arm/net/bpf_jit_32.c @@ -930,4 +930,5 @@ void bpf_jit_free(struct sk_filter *fp) { if (fp->bpf_func != sk_run_filter) module_free(NULL, fp->bpf_func); + kfree(fp); } diff --git a/arch/powerpc/net/bpf_jit_comp.c b/arch/powerpc/net/bpf_jit_comp.c index bf56e33f8257..2345bdb4d917 100644 --- a/arch/powerpc/net/bpf_jit_comp.c +++ b/arch/powerpc/net/bpf_jit_comp.c @@ -691,4 +691,5 @@ void bpf_jit_free(struct sk_filter *fp) { if (fp->bpf_func != sk_run_filter) module_free(NULL, fp->bpf_func); + kfree(fp); } diff --git a/arch/s390/net/bpf_jit_comp.c b/arch/s390/net/bpf_jit_comp.c index 709239285869..a5df511e27a2 100644 --- a/arch/s390/net/bpf_jit_comp.c +++ b/arch/s390/net/bpf_jit_comp.c @@ -881,7 +881,9 @@ void bpf_jit_free(struct sk_filter *fp) struct bpf_binary_header *header = (void *)addr; if (fp->bpf_func == sk_run_filter) - return; + goto free_filter; set_memory_rw(addr, header->pages); module_free(NULL, header); +free_filter: + kfree(fp); } diff --git a/arch/sparc/net/bpf_jit_comp.c b/arch/sparc/net/bpf_jit_comp.c index 9c7be59e6f5a..218b6b23c378 100644 --- a/arch/sparc/net/bpf_jit_comp.c +++ b/arch/sparc/net/bpf_jit_comp.c @@ -808,4 +808,5 @@ void bpf_jit_free(struct sk_filter *fp) { if (fp->bpf_func != sk_run_filter) module_free(NULL, fp->bpf_func); + kfree(fp); } diff --git a/arch/x86/net/bpf_jit_comp.c b/arch/x86/net/bpf_jit_comp.c index 79c216aa0e2b..516593e1ce33 100644 --- a/arch/x86/net/bpf_jit_comp.c +++ b/arch/x86/net/bpf_jit_comp.c @@ -772,13 +772,21 @@ out: return; } +static void bpf_jit_free_deferred(struct work_struct *work) +{ + struct sk_filter *fp = container_of(work, struct sk_filter, work); + unsigned long addr = (unsigned long)fp->bpf_func & PAGE_MASK; + struct bpf_binary_header *header = (void *)addr; + + set_memory_rw(addr, header->pages); + module_free(NULL, header); + kfree(fp); +} + void bpf_jit_free(struct sk_filter *fp) { if (fp->bpf_func != sk_run_filter) { - unsigned long addr = (unsigned long)fp->bpf_func & PAGE_MASK; - struct bpf_binary_header *header = (void *)addr; - - set_memory_rw(addr, header->pages); - module_free(NULL, header); + INIT_WORK(&fp->work, bpf_jit_free_deferred); + schedule_work(&fp->work); } } diff --git a/include/linux/filter.h b/include/linux/filter.h index a6ac84871d6d..ff4e40cd45b1 100644 --- a/include/linux/filter.h +++ b/include/linux/filter.h @@ -6,6 +6,7 @@ #include #include +#include #include #ifdef CONFIG_COMPAT @@ -25,15 +26,19 @@ struct sk_filter { atomic_t refcnt; unsigned int len; /* Number of filter blocks */ + struct rcu_head rcu; unsigned int (*bpf_func)(const struct sk_buff *skb, const struct sock_filter *filter); - struct rcu_head rcu; - struct sock_filter insns[0]; + union { + struct sock_filter insns[0]; + struct work_struct work; + }; }; -static inline unsigned int sk_filter_len(const struct sk_filter *fp) +static inline unsigned int sk_filter_size(unsigned int proglen) { - return fp->len * sizeof(struct sock_filter) + sizeof(*fp); + return max(sizeof(struct sk_filter), + offsetof(struct sk_filter, insns[proglen])); } extern int sk_filter(struct sock *sk, struct sk_buff *skb); @@ -67,11 +72,13 @@ static inline void bpf_jit_dump(unsigned int flen, unsigned int proglen, } #define SK_RUN_FILTER(FILTER, SKB) (*FILTER->bpf_func)(SKB, FILTER->insns) #else +#include static inline void bpf_jit_compile(struct sk_filter *fp) { } static inline void bpf_jit_free(struct sk_filter *fp) { + kfree(fp); } #define SK_RUN_FILTER(FILTER, SKB) sk_run_filter(SKB, FILTER->insns) #endif diff --git a/include/net/sock.h b/include/net/sock.h index 1d37a8086bed..808cbc2ec6c1 100644 --- a/include/net/sock.h +++ b/include/net/sock.h @@ -1630,16 +1630,14 @@ static inline void sk_filter_release(struct sk_filter *fp) static inline void sk_filter_uncharge(struct sock *sk, struct sk_filter *fp) { - unsigned int size = sk_filter_len(fp); - - atomic_sub(size, &sk->sk_omem_alloc); + atomic_sub(sk_filter_size(fp->len), &sk->sk_omem_alloc); sk_filter_release(fp); } static inline void sk_filter_charge(struct sock *sk, struct sk_filter *fp) { atomic_inc(&fp->refcnt); - atomic_add(sk_filter_len(fp), &sk->sk_omem_alloc); + atomic_add(sk_filter_size(fp->len), &sk->sk_omem_alloc); } /* diff --git a/net/core/filter.c b/net/core/filter.c index 6438f29ff266..01b780856db2 100644 --- a/net/core/filter.c +++ b/net/core/filter.c @@ -644,7 +644,6 @@ void sk_filter_release_rcu(struct rcu_head *rcu) struct sk_filter *fp = container_of(rcu, struct sk_filter, rcu); bpf_jit_free(fp); - kfree(fp); } EXPORT_SYMBOL(sk_filter_release_rcu); @@ -683,7 +682,7 @@ int sk_unattached_filter_create(struct sk_filter **pfp, if (fprog->filter == NULL) return -EINVAL; - fp = kmalloc(fsize + sizeof(*fp), GFP_KERNEL); + fp = kmalloc(sk_filter_size(fprog->len), GFP_KERNEL); if (!fp) return -ENOMEM; memcpy(fp->insns, fprog->filter, fsize); @@ -723,6 +722,7 @@ int sk_attach_filter(struct sock_fprog *fprog, struct sock *sk) { struct sk_filter *fp, *old_fp; unsigned int fsize = sizeof(struct sock_filter) * fprog->len; + unsigned int sk_fsize = sk_filter_size(fprog->len); int err; if (sock_flag(sk, SOCK_FILTER_LOCKED)) @@ -732,11 +732,11 @@ int sk_attach_filter(struct sock_fprog *fprog, struct sock *sk) if (fprog->filter == NULL) return -EINVAL; - fp = sock_kmalloc(sk, fsize+sizeof(*fp), GFP_KERNEL); + fp = sock_kmalloc(sk, sk_fsize, GFP_KERNEL); if (!fp) return -ENOMEM; if (copy_from_user(fp->insns, fprog->filter, fsize)) { - sock_kfree_s(sk, fp, fsize+sizeof(*fp)); + sock_kfree_s(sk, fp, sk_fsize); return -EFAULT; } -- cgit v1.2.3 From 3f0116c3238a96bc18ad4b4acefe4e7be32fa861 Mon Sep 17 00:00:00 2001 From: Ingo Molnar Date: Thu, 10 Oct 2013 10:16:30 +0200 Subject: compiler/gcc4: Add quirk for 'asm goto' miscompilation bug Fengguang Wu, Oleg Nesterov and Peter Zijlstra tracked down a kernel crash to a GCC bug: GCC miscompiles certain 'asm goto' constructs, as outlined here: http://gcc.gnu.org/bugzilla/show_bug.cgi?id=58670 Implement a workaround suggested by Jakub Jelinek. Reported-and-tested-by: Fengguang Wu Reported-by: Oleg Nesterov Reported-by: Peter Zijlstra Suggested-by: Jakub Jelinek Reviewed-by: Richard Henderson Cc: Linus Torvalds Cc: Andrew Morton Cc: Signed-off-by: Ingo Molnar --- arch/arm/include/asm/jump_label.h | 2 +- arch/mips/include/asm/jump_label.h | 2 +- arch/powerpc/include/asm/jump_label.h | 2 +- arch/s390/include/asm/jump_label.h | 2 +- arch/sparc/include/asm/jump_label.h | 2 +- arch/x86/include/asm/cpufeature.h | 6 +++--- arch/x86/include/asm/jump_label.h | 2 +- arch/x86/include/asm/mutex_64.h | 4 ++-- include/linux/compiler-gcc4.h | 15 +++++++++++++++ 9 files changed, 26 insertions(+), 11 deletions(-) (limited to 'arch/sparc') diff --git a/arch/arm/include/asm/jump_label.h b/arch/arm/include/asm/jump_label.h index bfc198c75913..863c892b4aaa 100644 --- a/arch/arm/include/asm/jump_label.h +++ b/arch/arm/include/asm/jump_label.h @@ -16,7 +16,7 @@ static __always_inline bool arch_static_branch(struct static_key *key) { - asm goto("1:\n\t" + asm_volatile_goto("1:\n\t" JUMP_LABEL_NOP "\n\t" ".pushsection __jump_table, \"aw\"\n\t" ".word 1b, %l[l_yes], %c0\n\t" diff --git a/arch/mips/include/asm/jump_label.h b/arch/mips/include/asm/jump_label.h index 4d6d77ed9b9d..e194f957ca8c 100644 --- a/arch/mips/include/asm/jump_label.h +++ b/arch/mips/include/asm/jump_label.h @@ -22,7 +22,7 @@ static __always_inline bool arch_static_branch(struct static_key *key) { - asm goto("1:\tnop\n\t" + asm_volatile_goto("1:\tnop\n\t" "nop\n\t" ".pushsection __jump_table, \"aw\"\n\t" WORD_INSN " 1b, %l[l_yes], %0\n\t" diff --git a/arch/powerpc/include/asm/jump_label.h b/arch/powerpc/include/asm/jump_label.h index ae098c438f00..f016bb699b5f 100644 --- a/arch/powerpc/include/asm/jump_label.h +++ b/arch/powerpc/include/asm/jump_label.h @@ -19,7 +19,7 @@ static __always_inline bool arch_static_branch(struct static_key *key) { - asm goto("1:\n\t" + asm_volatile_goto("1:\n\t" "nop\n\t" ".pushsection __jump_table, \"aw\"\n\t" JUMP_ENTRY_TYPE "1b, %l[l_yes], %c0\n\t" diff --git a/arch/s390/include/asm/jump_label.h b/arch/s390/include/asm/jump_label.h index 6c32190dc73e..346b1c85ffb4 100644 --- a/arch/s390/include/asm/jump_label.h +++ b/arch/s390/include/asm/jump_label.h @@ -15,7 +15,7 @@ static __always_inline bool arch_static_branch(struct static_key *key) { - asm goto("0: brcl 0,0\n" + asm_volatile_goto("0: brcl 0,0\n" ".pushsection __jump_table, \"aw\"\n" ASM_ALIGN "\n" ASM_PTR " 0b, %l[label], %0\n" diff --git a/arch/sparc/include/asm/jump_label.h b/arch/sparc/include/asm/jump_label.h index 5080d16a832f..ec2e2e2aba7d 100644 --- a/arch/sparc/include/asm/jump_label.h +++ b/arch/sparc/include/asm/jump_label.h @@ -9,7 +9,7 @@ static __always_inline bool arch_static_branch(struct static_key *key) { - asm goto("1:\n\t" + asm_volatile_goto("1:\n\t" "nop\n\t" "nop\n\t" ".pushsection __jump_table, \"aw\"\n\t" diff --git a/arch/x86/include/asm/cpufeature.h b/arch/x86/include/asm/cpufeature.h index d3f5c63078d8..89270b4318db 100644 --- a/arch/x86/include/asm/cpufeature.h +++ b/arch/x86/include/asm/cpufeature.h @@ -374,7 +374,7 @@ static __always_inline __pure bool __static_cpu_has(u16 bit) * Catch too early usage of this before alternatives * have run. */ - asm goto("1: jmp %l[t_warn]\n" + asm_volatile_goto("1: jmp %l[t_warn]\n" "2:\n" ".section .altinstructions,\"a\"\n" " .long 1b - .\n" @@ -388,7 +388,7 @@ static __always_inline __pure bool __static_cpu_has(u16 bit) #endif - asm goto("1: jmp %l[t_no]\n" + asm_volatile_goto("1: jmp %l[t_no]\n" "2:\n" ".section .altinstructions,\"a\"\n" " .long 1b - .\n" @@ -453,7 +453,7 @@ static __always_inline __pure bool _static_cpu_has_safe(u16 bit) * have. Thus, we force the jump to the widest, 4-byte, signed relative * offset even though the last would often fit in less bytes. */ - asm goto("1: .byte 0xe9\n .long %l[t_dynamic] - 2f\n" + asm_volatile_goto("1: .byte 0xe9\n .long %l[t_dynamic] - 2f\n" "2:\n" ".section .altinstructions,\"a\"\n" " .long 1b - .\n" /* src offset */ diff --git a/arch/x86/include/asm/jump_label.h b/arch/x86/include/asm/jump_label.h index 64507f35800c..6a2cefb4395a 100644 --- a/arch/x86/include/asm/jump_label.h +++ b/arch/x86/include/asm/jump_label.h @@ -18,7 +18,7 @@ static __always_inline bool arch_static_branch(struct static_key *key) { - asm goto("1:" + asm_volatile_goto("1:" ".byte " __stringify(STATIC_KEY_INIT_NOP) "\n\t" ".pushsection __jump_table, \"aw\" \n\t" _ASM_ALIGN "\n\t" diff --git a/arch/x86/include/asm/mutex_64.h b/arch/x86/include/asm/mutex_64.h index e7e6751648ed..07537a44216e 100644 --- a/arch/x86/include/asm/mutex_64.h +++ b/arch/x86/include/asm/mutex_64.h @@ -20,7 +20,7 @@ static inline void __mutex_fastpath_lock(atomic_t *v, void (*fail_fn)(atomic_t *)) { - asm volatile goto(LOCK_PREFIX " decl %0\n" + asm_volatile_goto(LOCK_PREFIX " decl %0\n" " jns %l[exit]\n" : : "m" (v->counter) : "memory", "cc" @@ -75,7 +75,7 @@ static inline int __mutex_fastpath_lock_retval(atomic_t *count) static inline void __mutex_fastpath_unlock(atomic_t *v, void (*fail_fn)(atomic_t *)) { - asm volatile goto(LOCK_PREFIX " incl %0\n" + asm_volatile_goto(LOCK_PREFIX " incl %0\n" " jg %l[exit]\n" : : "m" (v->counter) : "memory", "cc" diff --git a/include/linux/compiler-gcc4.h b/include/linux/compiler-gcc4.h index 842de225055f..ded429966c1f 100644 --- a/include/linux/compiler-gcc4.h +++ b/include/linux/compiler-gcc4.h @@ -65,6 +65,21 @@ #define __visible __attribute__((externally_visible)) #endif +/* + * GCC 'asm goto' miscompiles certain code sequences: + * + * http://gcc.gnu.org/bugzilla/show_bug.cgi?id=58670 + * + * Work it around via a compiler barrier quirk suggested by Jakub Jelinek. + * Fixed in GCC 4.8.2 and later versions. + * + * (asm goto is automatically volatile - the naming reflects this.) + */ +#if GCC_VERSION <= 40801 +# define asm_volatile_goto(x...) do { asm goto(x); asm (""); } while (0) +#else +# define asm_volatile_goto(x...) do { asm goto(x); } while (0) +#endif #ifdef CONFIG_ARCH_USE_BUILTIN_BSWAP #if GCC_VERSION >= 40400 -- cgit v1.2.3