October 2025 - Linux-stable-mirror

[PATCH v2 01/11] powerpc/64s/slb: Fix SLB multihit issue during SLB preload

by Ritesh Harjani (IBM)

From: Donet Tom <donettom(a)linux.ibm.com> On systems using the hash MMU, there is a software SLB preload cache that mirrors the entries loaded into the hardware SLB buffer. This preload cache is subject to periodic eviction — typically after every 256 context switches — to remove old entry. To optimize performance, the kernel skips switch_mmu_context() in switch_mm_irqs_off() when the prev and next mm_struct are the same. However, on hash MMU systems, this can lead to inconsistencies between the hardware SLB and the software preload cache. If an SLB entry for a process is evicted from the software cache on one CPU, and the same process later runs on another CPU without executing switch_mmu_context(), the hardware SLB may retain stale entries. If the kernel then attempts to reload that entry, it can trigger an SLB multi-hit error. The following timeline shows how stale SLB entries are created and can cause a multi-hit error when a process moves between CPUs without a MMU context switch. CPU 0 CPU 1 ----- ----- Process P exec swapper/1 load_elf_binary begin_new_exc activate_mm switch_mm_irqs_off switch_mmu_context switch_slb /* * This invalidates all * the entries in the HW * and setup the new HW * SLB entries as per the * preload cache. */ context_switch sched_migrate_task migrates process P to cpu-1 Process swapper/0 context switch (to process P) (uses mm_struct of Process P) switch_mm_irqs_off() switch_slb load_slb++ /* * load_slb becomes 0 here * and we evict an entry from * the preload cache with * preload_age(). We still * keep HW SLB and preload * cache in sync, that is * because all HW SLB entries * anyways gets evicted in * switch_slb during SLBIA. * We then only add those * entries back in HW SLB, * which are currently * present in preload_cache * (after eviction). */ load_elf_binary continues... setup_new_exec() slb_setup_new_exec() sched_switch event sched_migrate_task migrates process P to cpu-0 context_switch from swapper/0 to Process P switch_mm_irqs_off() /* * Since both prev and next mm struct are same we don't call * switch_mmu_context(). This will cause the HW SLB and SW preload * cache to go out of sync in preload_new_slb_context. Because there * was an SLB entry which was evicted from both HW and preload cache * on cpu-1. Now later in preload_new_slb_context(), when we will try * to add the same preload entry again, we will add this to the SW * preload cache and then will add it to the HW SLB. Since on cpu-0 * this entry was never invalidated, hence adding this entry to the HW * SLB will cause a SLB multi-hit error. */ load_elf_binary continues... START_THREAD start_thread preload_new_slb_context /* * This tries to add a new EA to preload cache which was earlier * evicted from both cpu-1 HW SLB and preload cache. This caused the * HW SLB of cpu-0 to go out of sync with the SW preload cache. The * reason for this was, that when we context switched back on CPU-0, * we should have ideally called switch_mmu_context() which will * bring the HW SLB entries on CPU-0 in sync with SW preload cache * entries by setting up the mmu context properly. But we didn't do * that since the prev mm_struct running on cpu-0 was same as the * next mm_struct (which is true for swapper / kernel threads). So * now when we try to add this new entry into the HW SLB of cpu-0, * we hit a SLB multi-hit error. */ WARNING: CPU: 0 PID: 1810970 at arch/powerpc/mm/book3s64/slb.c:62 assert_slb_presence+0x2c/0x50(48 results) 02:47:29 [20157/42149] Modules linked in: CPU: 0 UID: 0 PID: 1810970 Comm: dd Not tainted 6.16.0-rc3-dirty #12 VOLUNTARY Hardware name: IBM pSeries (emulated by qemu) POWER8 (architected) 0x4d0200 0xf000004 of:SLOF,HEAD hv:linux,kvm pSeries NIP: c00000000015426c LR: c0000000001543b4 CTR: 0000000000000000 REGS: c0000000497c77e0 TRAP: 0700 Not tainted (6.16.0-rc3-dirty) MSR: 8000000002823033 <SF,VEC,VSX,FP,ME,IR,DR,RI,LE> CR: 28888482 XER: 00000000 CFAR: c0000000001543b0 IRQMASK: 3 <...> NIP [c00000000015426c] assert_slb_presence+0x2c/0x50 LR [c0000000001543b4] slb_insert_entry+0x124/0x390 Call Trace: 0x7fffceb5ffff (unreliable) preload_new_slb_context+0x100/0x1a0 start_thread+0x26c/0x420 load_elf_binary+0x1b04/0x1c40 bprm_execve+0x358/0x680 do_execveat_common+0x1f8/0x240 sys_execve+0x58/0x70 system_call_exception+0x114/0x300 system_call_common+0x160/0x2c4 >From the above analysis, during early exec the hardware SLB is cleared, and entries from the software preload cache are reloaded into hardware by switch_slb. However, preload_new_slb_context and slb_setup_new_exec also attempt to load some of the same entries, which can trigger a multi-hit. In most cases, these additional preloads simply hit existing entries and add nothing new. Removing these functions avoids redundant preloads and eliminates the multi-hit issue. This patch removes these two functions. We tested process switching performance using the context_switch benchmark on POWER9/hash, and observed no regression. Without this patch: 129041 ops/sec With this patch: 129341 ops/sec We also measured SLB faults during boot, and the counts are essentially the same with and without this patch. SLB faults without this patch: 19727 SLB faults with this patch: 19786 Cc: Madhavan Srinivasan <maddy(a)linux.ibm.com> Cc: Michael Ellerman <mpe(a)ellerman.id.au> Cc: Nicholas Piggin <npiggin(a)gmail.com> Cc: Christophe Leroy <christophe.leroy(a)csgroup.eu> Cc: Paul Mackerras <paulus(a)ozlabs.org> Cc: Aneesh Kumar K.V <aneesh.kumar(a)kernel.org> Cc: Donet Tom <donettom(a)linux.ibm.com> Cc: <linuxppc-dev(a)lists.ozlabs.org> Fixes: 5434ae74629a ("powerpc/64s/hash: Add a SLB preload cache") cc: <stable(a)vger.kernel.org> Suggested-by: Nicholas Piggin <npiggin(a)gmail.com> Signed-off-by: Donet Tom <donettom(a)linux.ibm.com> Signed-off-by: Ritesh Harjani (IBM) <ritesh.list(a)gmail.com> --- arch/powerpc/include/asm/book3s/64/mmu-hash.h | 1 - arch/powerpc/kernel/process.c | 5 -- arch/powerpc/mm/book3s64/internal.h | 2 - arch/powerpc/mm/book3s64/mmu_context.c | 2 - arch/powerpc/mm/book3s64/slb.c | 88 ------------------- 5 files changed, 98 deletions(-) diff --git a/arch/powerpc/include/asm/book3s/64/mmu-hash.h b/arch/powerpc/include/asm/book3s/64/mmu-hash.h index 346351423207..af12e2ba8eb8 100644 --- a/arch/powerpc/include/asm/book3s/64/mmu-hash.h +++ b/arch/powerpc/include/asm/book3s/64/mmu-hash.h @@ -524,7 +524,6 @@ void slb_save_contents(struct slb_entry *slb_ptr); void slb_dump_contents(struct slb_entry *slb_ptr); extern void slb_vmalloc_update(void); -void preload_new_slb_context(unsigned long start, unsigned long sp); #ifdef CONFIG_PPC_64S_HASH_MMU void slb_set_size(u16 size); diff --git a/arch/powerpc/kernel/process.c b/arch/powerpc/kernel/process.c index eb23966ac0a9..a45fe147868b 100644 --- a/arch/powerpc/kernel/process.c +++ b/arch/powerpc/kernel/process.c @@ -1897,8 +1897,6 @@ int copy_thread(struct task_struct *p, const struct kernel_clone_args *args) return 0; } -void preload_new_slb_context(unsigned long start, unsigned long sp); - /* * Set up a thread for executing a new program */ @@ -1906,9 +1904,6 @@ void start_thread(struct pt_regs *regs, unsigned long start, unsigned long sp) { #ifdef CONFIG_PPC64 unsigned long load_addr = regs->gpr[2]; /* saved by ELF_PLAT_INIT */ - - if (IS_ENABLED(CONFIG_PPC_BOOK3S_64) && !radix_enabled()) - preload_new_slb_context(start, sp); #endif #ifdef CONFIG_PPC_TRANSACTIONAL_MEM diff --git a/arch/powerpc/mm/book3s64/internal.h b/arch/powerpc/mm/book3s64/internal.h index a57a25f06a21..c26a6f0c90fc 100644 --- a/arch/powerpc/mm/book3s64/internal.h +++ b/arch/powerpc/mm/book3s64/internal.h @@ -24,8 +24,6 @@ static inline bool stress_hpt(void) void hpt_do_stress(unsigned long ea, unsigned long hpte_group); -void slb_setup_new_exec(void); - void exit_lazy_flush_tlb(struct mm_struct *mm, bool always_flush); #endif /* ARCH_POWERPC_MM_BOOK3S64_INTERNAL_H */ diff --git a/arch/powerpc/mm/book3s64/mmu_context.c b/arch/powerpc/mm/book3s64/mmu_context.c index 4e1e45420bd4..fb9dcf9ca599 100644 --- a/arch/powerpc/mm/book3s64/mmu_context.c +++ b/arch/powerpc/mm/book3s64/mmu_context.c @@ -150,8 +150,6 @@ static int hash__init_new_context(struct mm_struct *mm) void hash__setup_new_exec(void) { slice_setup_new_exec(); - - slb_setup_new_exec(); } #else static inline int hash__init_new_context(struct mm_struct *mm) diff --git a/arch/powerpc/mm/book3s64/slb.c b/arch/powerpc/mm/book3s64/slb.c index 6b783552403c..7e053c561a09 100644 --- a/arch/powerpc/mm/book3s64/slb.c +++ b/arch/powerpc/mm/book3s64/slb.c @@ -328,94 +328,6 @@ static void preload_age(struct thread_info *ti) ti->slb_preload_tail = (ti->slb_preload_tail + 1) % SLB_PRELOAD_NR; } -void slb_setup_new_exec(void) -{ - struct thread_info *ti = current_thread_info(); - struct mm_struct *mm = current->mm; - unsigned long exec = 0x10000000; - - WARN_ON(irqs_disabled()); - - /* - * preload cache can only be used to determine whether a SLB - * entry exists if it does not start to overflow. - */ - if (ti->slb_preload_nr + 2 > SLB_PRELOAD_NR) - return; - - hard_irq_disable(); - - /* - * We have no good place to clear the slb preload cache on exec, - * flush_thread is about the earliest arch hook but that happens - * after we switch to the mm and have already preloaded the SLBEs. - * - * For the most part that's probably okay to use entries from the - * previous exec, they will age out if unused. It may turn out to - * be an advantage to clear the cache before switching to it, - * however. - */ - - /* - * preload some userspace segments into the SLB. - * Almost all 32 and 64bit PowerPC executables are linked at - * 0x10000000 so it makes sense to preload this segment. - */ - if (!is_kernel_addr(exec)) { - if (preload_add(ti, exec)) - slb_allocate_user(mm, exec); - } - - /* Libraries and mmaps. */ - if (!is_kernel_addr(mm->mmap_base)) { - if (preload_add(ti, mm->mmap_base)) - slb_allocate_user(mm, mm->mmap_base); - } - - /* see switch_slb */ - asm volatile("isync" : : : "memory"); - - local_irq_enable(); -} - -void preload_new_slb_context(unsigned long start, unsigned long sp) -{ - struct thread_info *ti = current_thread_info(); - struct mm_struct *mm = current->mm; - unsigned long heap = mm->start_brk; - - WARN_ON(irqs_disabled()); - - /* see above */ - if (ti->slb_preload_nr + 3 > SLB_PRELOAD_NR) - return; - - hard_irq_disable(); - - /* Userspace entry address. */ - if (!is_kernel_addr(start)) { - if (preload_add(ti, start)) - slb_allocate_user(mm, start); - } - - /* Top of stack, grows down. */ - if (!is_kernel_addr(sp)) { - if (preload_add(ti, sp)) - slb_allocate_user(mm, sp); - } - - /* Bottom of heap, grows up. */ - if (heap && !is_kernel_addr(heap)) { - if (preload_add(ti, heap)) - slb_allocate_user(mm, heap); - } - - /* see switch_slb */ - asm volatile("isync" : : : "memory"); - - local_irq_enable(); -} - static void slb_cache_slbie_kernel(unsigned int index) { unsigned long slbie_data = get_paca()->slb_cache[index]; -- 2.51.0

1 week, 4 days

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[PATCH v5 0/3] phy: qcom: edp: Add missing ref clock to x1e80100

by Abel Vesa

According to documentation, the DP PHY on x1e80100 has another clock called ref. The current X Elite devices supported upstream work fine without this clock, because the boot firmware leaves this clock enabled. But we should not rely on that. Also, when it comes to power management, this clock needs to be also disabled on suspend. So even though this change breaks the ABI, it is needed in order to make we disable this clock on runtime PM, when that is going to be enabled in the driver. So rework the driver to allow different number of clocks, fix the dt-bindings schema and add the clock to the DT node as well. Signed-off-by: Abel Vesa <abel.vesa(a)linaro.org> --- Changes in v5: - Picked-up Bjorn's R-b tags. - Replaced "parse" with "get" on clocks acquiring failure. - Link to v4: https://lore.kernel.org/r/20251029-phy-qcom-edp-add-missing-refclk-v4-0-adb… Changes in v4: - Picked Dmitry's R-b tag for the driver patch - Added x1e80100 substring to subject of dts patch - Link to v3 (resend): https://lore.kernel.org/r/20251014-phy-qcom-edp-add-missing-refclk-v3-0-078… Changes in v3 (resend) - picked-up Krzysztof's R-b tag for bindings patch - Link to v3: https://lore.kernel.org/r/20250909-phy-qcom-edp-add-missing-refclk-v3-0-4ec… Changes in v3: - Use dev_err_probe() on clocks parsing failure. - Explain why the ABI break is necessary. - Drop the extra 'clk' suffix from the clock name. So ref instead of refclk. - Link to v2: https://lore.kernel.org/r/20250903-phy-qcom-edp-add-missing-refclk-v2-0-d88… Changes in v2: - Fix schema by adding the minItems, as suggested by Krzysztof. - Use devm_clk_bulk_get_all, as suggested by Konrad. - Rephrase the commit messages to reflect the flexible number of clocks. - Link to v1: https://lore.kernel.org/r/20250730-phy-qcom-edp-add-missing-refclk-v1-0-6f7… --- Abel Vesa (3): dt-bindings: phy: qcom-edp: Add missing clock for X Elite phy: qcom: edp: Make the number of clocks flexible arm64: dts: qcom: x1e80100: Add missing TCSR ref clock to the DP PHYs .../devicetree/bindings/phy/qcom,edp-phy.yaml | 28 +++++++++++++++++++++- arch/arm64/boot/dts/qcom/hamoa.dtsi | 12 ++++++---- drivers/phy/qualcomm/phy-qcom-edp.c | 16 ++++++------- 3 files changed, 43 insertions(+), 13 deletions(-) --- base-commit: 131f3d9446a6075192cdd91f197989d98302faa6 change-id: 20250730-phy-qcom-edp-add-missing-refclk-5ab82828f8e7 Best regards, -- Abel Vesa <abel.vesa(a)linaro.org>

1 week, 4 days

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[PATCH v4 0/3] phy: qcom: edp: Add missing ref clock to x1e80100

by Abel Vesa

According to documentation, the DP PHY on x1e80100 has another clock called ref. The current X Elite devices supported upstream work fine without this clock, because the boot firmware leaves this clock enabled. But we should not rely on that. Also, when it comes to power management, this clock needs to be also disabled on suspend. So even though this change breaks the ABI, it is needed in order to make we disable this clock on runtime PM, when that is going to be enabled in the driver. So rework the driver to allow different number of clocks, fix the dt-bindings schema and add the clock to the DT node as well. Signed-off-by: Abel Vesa <abel.vesa(a)linaro.org> --- Changes in v4: - Picked Dmitry's R-b tag for the driver patch - Added x1e80100 substring to subject of dts patch - Link to v3 (resend): https://lore.kernel.org/r/20251014-phy-qcom-edp-add-missing-refclk-v3-0-078… Changes in v3 (resend) - picked-up Krzysztof's R-b tag for bindings patch - Link to v3: https://lore.kernel.org/r/20250909-phy-qcom-edp-add-missing-refclk-v3-0-4ec… Changes in v3: - Use dev_err_probe() on clocks parsing failure. - Explain why the ABI break is necessary. - Drop the extra 'clk' suffix from the clock name. So ref instead of refclk. - Link to v2: https://lore.kernel.org/r/20250903-phy-qcom-edp-add-missing-refclk-v2-0-d88… Changes in v2: - Fix schema by adding the minItems, as suggested by Krzysztof. - Use devm_clk_bulk_get_all, as suggested by Konrad. - Rephrase the commit messages to reflect the flexible number of clocks. - Link to v1: https://lore.kernel.org/r/20250730-phy-qcom-edp-add-missing-refclk-v1-0-6f7… --- Abel Vesa (3): dt-bindings: phy: qcom-edp: Add missing clock for X Elite phy: qcom: edp: Make the number of clocks flexible arm64: dts: qcom: x1e80100: Add missing TCSR ref clock to the DP PHYs .../devicetree/bindings/phy/qcom,edp-phy.yaml | 28 +++++++++++++++++++++- arch/arm64/boot/dts/qcom/hamoa.dtsi | 12 ++++++---- drivers/phy/qualcomm/phy-qcom-edp.c | 16 ++++++------- 3 files changed, 43 insertions(+), 13 deletions(-) --- base-commit: f9ba12abc5282bf992f9a9ae87ad814fd03a0270 change-id: 20250730-phy-qcom-edp-add-missing-refclk-5ab82828f8e7 Best regards, -- Abel Vesa <abel.vesa(a)linaro.org>

1 week, 4 days

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[PATCH v2 1/4] ASoC: cs4271: Fix cs4271 I2C and SPI drivers automatic module loading

by Herve Codina

In commit c973b8a7dc50 ("ASoC: cs4271: Split SPI and I2C code into different modules") the driver was slit into a core, an SPI and an I2C part. However, the MODULE_DEVICE_TABLE(of, cs4271_dt_ids) was in the core part and so, module loading based on module.alias (based on DT compatible string matching) loads the core part but not the SPI or I2C parts. In order to have the I2C or the SPI module loaded automatically, move the MODULE_DEVICE_TABLE(of, ...) the core to I2C and SPI parts. Also move cs4271_dt_ids itself from the core part to I2C and SPI parts as both the call to MODULE_DEVICE_TABLE(of, ...) and the cs4271_dt_ids table itself need to be in the same file. Fixes: c973b8a7dc50 ("ASoC: cs4271: Split SPI and I2C code into different modules") Cc: stable(a)vger.kernel.org Signed-off-by: Herve Codina <herve.codina(a)bootlin.com> --- sound/soc/codecs/cs4271-i2c.c | 6 ++++++ sound/soc/codecs/cs4271-spi.c | 13 +++++++++++++ sound/soc/codecs/cs4271.c | 9 --------- sound/soc/codecs/cs4271.h | 1 - 4 files changed, 19 insertions(+), 10 deletions(-) diff --git a/sound/soc/codecs/cs4271-i2c.c b/sound/soc/codecs/cs4271-i2c.c index 1d210b969173..cefb8733fc61 100644 --- a/sound/soc/codecs/cs4271-i2c.c +++ b/sound/soc/codecs/cs4271-i2c.c @@ -28,6 +28,12 @@ static const struct i2c_device_id cs4271_i2c_id[] = { }; MODULE_DEVICE_TABLE(i2c, cs4271_i2c_id); +static const struct of_device_id cs4271_dt_ids[] = { + { .compatible = "cirrus,cs4271", }, + { } +}; +MODULE_DEVICE_TABLE(of, cs4271_dt_ids); + static struct i2c_driver cs4271_i2c_driver = { .driver = { .name = "cs4271", diff --git a/sound/soc/codecs/cs4271-spi.c b/sound/soc/codecs/cs4271-spi.c index 4feb80436bd9..28dd7b8f3507 100644 --- a/sound/soc/codecs/cs4271-spi.c +++ b/sound/soc/codecs/cs4271-spi.c @@ -23,11 +23,24 @@ static int cs4271_spi_probe(struct spi_device *spi) return cs4271_probe(&spi->dev, devm_regmap_init_spi(spi, &config)); } +static const struct spi_device_id cs4271_id_spi[] = { + { "cs4271", 0 }, + {} +}; +MODULE_DEVICE_TABLE(spi, cs4271_id_spi); + +static const struct of_device_id cs4271_dt_ids[] = { + { .compatible = "cirrus,cs4271", }, + { } +}; +MODULE_DEVICE_TABLE(of, cs4271_dt_ids); + static struct spi_driver cs4271_spi_driver = { .driver = { .name = "cs4271", .of_match_table = of_match_ptr(cs4271_dt_ids), }, + .id_table = cs4271_id_spi, .probe = cs4271_spi_probe, }; module_spi_driver(cs4271_spi_driver); diff --git a/sound/soc/codecs/cs4271.c b/sound/soc/codecs/cs4271.c index 6a3cca3d26c7..ff9c6628224c 100644 --- a/sound/soc/codecs/cs4271.c +++ b/sound/soc/codecs/cs4271.c @@ -543,15 +543,6 @@ static int cs4271_soc_resume(struct snd_soc_component *component) #define cs4271_soc_resume NULL #endif /* CONFIG_PM */ -#ifdef CONFIG_OF -const struct of_device_id cs4271_dt_ids[] = { - { .compatible = "cirrus,cs4271", }, - { } -}; -MODULE_DEVICE_TABLE(of, cs4271_dt_ids); -EXPORT_SYMBOL_GPL(cs4271_dt_ids); -#endif - static int cs4271_component_probe(struct snd_soc_component *component) { struct cs4271_private *cs4271 = snd_soc_component_get_drvdata(component); diff --git a/sound/soc/codecs/cs4271.h b/sound/soc/codecs/cs4271.h index 290283a9149e..4965ce085875 100644 --- a/sound/soc/codecs/cs4271.h +++ b/sound/soc/codecs/cs4271.h @@ -4,7 +4,6 @@ #include <linux/regmap.h> -extern const struct of_device_id cs4271_dt_ids[]; extern const struct regmap_config cs4271_regmap_config; int cs4271_probe(struct device *dev, struct regmap *regmap); -- 2.51.0

1 week, 4 days

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[PATCH v2] Bluetooth: rfcomm: fix modem control handling

by Johan Hovold

The RFCOMM driver confuses the local and remote modem control signals, which specifically means that the reported DTR and RTS state will instead reflect the remote end (i.e. DSR and CTS). This issue dates back to the original driver (and a follow-on update) merged in 2002, which resulted in a non-standard implementation of TIOCMSET that allowed controlling also the TS07.10 IC and DV signals by mapping them to the RI and DCD input flags, while TIOCMGET failed to return the actual state of DTR and RTS. Note that the bogus control of input signals in tiocmset() is just dead code as those flags will have been masked out by the tty layer since 2003. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Cc: stable(a)vger.kernel.org Signed-off-by: Johan Hovold <johan(a)kernel.org> --- Changes in v2 - fix a compilation issue discovered before sending v1 but never folded into the actual patch... net/bluetooth/rfcomm/tty.c | 26 +++++++++++--------------- 1 file changed, 11 insertions(+), 15 deletions(-) diff --git a/net/bluetooth/rfcomm/tty.c b/net/bluetooth/rfcomm/tty.c index 376ce6de84be..b783526ab588 100644 --- a/net/bluetooth/rfcomm/tty.c +++ b/net/bluetooth/rfcomm/tty.c @@ -643,8 +643,8 @@ static void rfcomm_dev_modem_status(struct rfcomm_dlc *dlc, u8 v24_sig) tty_port_tty_hangup(&dev->port, true); dev->modem_status = - ((v24_sig & RFCOMM_V24_RTC) ? (TIOCM_DSR | TIOCM_DTR) : 0) | - ((v24_sig & RFCOMM_V24_RTR) ? (TIOCM_RTS | TIOCM_CTS) : 0) | + ((v24_sig & RFCOMM_V24_RTC) ? TIOCM_DSR : 0) | + ((v24_sig & RFCOMM_V24_RTR) ? TIOCM_CTS : 0) | ((v24_sig & RFCOMM_V24_IC) ? TIOCM_RI : 0) | ((v24_sig & RFCOMM_V24_DV) ? TIOCM_CD : 0); } @@ -1055,10 +1055,14 @@ static void rfcomm_tty_hangup(struct tty_struct *tty) static int rfcomm_tty_tiocmget(struct tty_struct *tty) { struct rfcomm_dev *dev = tty->driver_data; + struct rfcomm_dlc *dlc = dev->dlc; + u8 v24_sig; BT_DBG("tty %p dev %p", tty, dev); - return dev->modem_status; + rfcomm_dlc_get_modem_status(dlc, &v24_sig); + + return (v24_sig & (TIOCM_DTR | TIOCM_RTS)) | dev->modem_status; } static int rfcomm_tty_tiocmset(struct tty_struct *tty, unsigned int set, unsigned int clear) @@ -1071,23 +1075,15 @@ static int rfcomm_tty_tiocmset(struct tty_struct *tty, unsigned int set, unsigne rfcomm_dlc_get_modem_status(dlc, &v24_sig); - if (set & TIOCM_DSR || set & TIOCM_DTR) + if (set & TIOCM_DTR) v24_sig |= RFCOMM_V24_RTC; - if (set & TIOCM_RTS || set & TIOCM_CTS) + if (set & TIOCM_RTS) v24_sig |= RFCOMM_V24_RTR; - if (set & TIOCM_RI) - v24_sig |= RFCOMM_V24_IC; - if (set & TIOCM_CD) - v24_sig |= RFCOMM_V24_DV; - if (clear & TIOCM_DSR || clear & TIOCM_DTR) + if (clear & TIOCM_DTR) v24_sig &= ~RFCOMM_V24_RTC; - if (clear & TIOCM_RTS || clear & TIOCM_CTS) + if (clear & TIOCM_RTS) v24_sig &= ~RFCOMM_V24_RTR; - if (clear & TIOCM_RI) - v24_sig &= ~RFCOMM_V24_IC; - if (clear & TIOCM_CD) - v24_sig &= ~RFCOMM_V24_DV; rfcomm_dlc_set_modem_status(dlc, v24_sig); -- 2.49.1

1 week, 4 days

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btrfs task hung in `lock_extent` syzbot report and CVE-2024-35784

by Andrey Kalachev

Hi. I've check c-repro [1] on 6.1.y branch and found that repro still produce the crash on 6.1.y. I notice that syzbot bisection result [2] is incorrect: indeed, the hung was fixed by upstream commit b0ad381fa769 ("btrfs: fix deadlock with fiemap and extent locking"). Also, I saw CVE-2024-35784 [3][4] vulnerability, that have direct relation with that syzbot report. Therefore, syzbot reproducer provided additional way to check for CVE-2024-35784. I attempted to fix CVE-2024-35784 in stable 6.1.y (over v6.1.157), and found that the initial fix commit b0ad381fa769 ("btrfs: fix deadlock with fiemap and extent locking") introduced regressions [5][6]. IMHO here is the minimum patch series to eliminate CVE-2024-35784 from 6.1.y: b0ad381fa769 ("btrfs: fix deadlock with fiemap and extent locking") (Initial fix of the CVE-2024-35784) a1a4a9ca77f1 ("btrfs: fix race between ordered extent completion and fiemap") (Fixes: b0ad381fa769) 978b63f7464a ("btrfs: fix race when detecting delalloc ranges during fiemap") (Fixes: b0ad381fa769) 1cab1375ba6d ("btrfs: reuse cloned extent buffer during fiemap to avoid re-allocations") (Optimization: 978b63f7464a) 53e24158684b ("btrfs: set start on clone before calling copy_extent_buffer_full") (Fixes: 1cab1375ba6d) Required patches attached. Only two patches in the series have minor backport modifications due to v6.1.157 btrfs code differences. The remaining patches are identical to the upstream. Regards, AK Reported-by: syzbot+f8217aae382555004877(a)syzkaller.appspotmail.com ---- [1] https://syzkaller.appspot.com/text?tag=ReproC&x=12b4c88b280000 [2] https://syzkaller.appspot.com/bug?extid=f8217aae382555004877 [3] https://lore.kernel.org/all/2024051704-CVE-2024-35784-6dec@gregkh/ [4] https://cve.org/CVERecord/?id=CVE-2024-35784 [5] https://lore.kernel.org/linux-btrfs/cover.1709202499.git.fdmanana@suse.com/ [6] https://lore.kernel.org/all/20240304211551.880347593@linuxfoundation.org/

1 week, 4 days

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[PATCH v2 1/3] KVM: arm64: Make all 32bit ID registers fully writable

by Marc Zyngier

32bit ID registers aren't getting much love these days, and are often missed in updates. One of these updates broke restoring a GICv2 guest on a GICv3 machine. Instead of performing a piecemeal fix, just bite the bullet and make all 32bit ID regs fully writable. KVM itself never relies on them for anything, and if the VMM wants to mess up the guest, so be it. Fixes: 5cb57a1aff755 ("KVM: arm64: Zero ID_AA64PFR0_EL1.GIC when no GICv3 is presented to the guest") Reported-by: Peter Maydell <peter.maydell(a)linaro.org> Signed-off-by: Marc Zyngier <maz(a)kernel.org> Cc: stable(a)vger.kernel.org --- arch/arm64/kvm/sys_regs.c | 59 ++++++++++++++++++++------------------- 1 file changed, 31 insertions(+), 28 deletions(-) diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c index e67eb39ddc118..ad82264c6cbe1 100644 --- a/arch/arm64/kvm/sys_regs.c +++ b/arch/arm64/kvm/sys_regs.c @@ -2595,19 +2595,23 @@ static bool bad_redir_trap(struct kvm_vcpu *vcpu, .val = 0, \ } -/* sys_reg_desc initialiser for known cpufeature ID registers */ -#define AA32_ID_SANITISED(name) { \ - ID_DESC(name), \ - .visibility = aa32_id_visibility, \ - .val = 0, \ -} - /* sys_reg_desc initialiser for writable ID registers */ #define ID_WRITABLE(name, mask) { \ ID_DESC(name), \ .val = mask, \ } +/* + * 32bit ID regs are fully writable when the guest is 32bit + * capable. Nothing in the KVM code should rely on 32bit features + * anyway, only 64bit, so let the VMM do its worse. + */ +#define AA32_ID_WRITABLE(name) { \ + ID_DESC(name), \ + .visibility = aa32_id_visibility, \ + .val = GENMASK(31, 0), \ +} + /* sys_reg_desc initialiser for cpufeature ID registers that need filtering */ #define ID_FILTERED(sysreg, name, mask) { \ ID_DESC(sysreg), \ @@ -3128,40 +3132,39 @@ static const struct sys_reg_desc sys_reg_descs[] = { /* AArch64 mappings of the AArch32 ID registers */ /* CRm=1 */ - AA32_ID_SANITISED(ID_PFR0_EL1), - AA32_ID_SANITISED(ID_PFR1_EL1), + AA32_ID_WRITABLE(ID_PFR0_EL1), + AA32_ID_WRITABLE(ID_PFR1_EL1), { SYS_DESC(SYS_ID_DFR0_EL1), .access = access_id_reg, .get_user = get_id_reg, .set_user = set_id_dfr0_el1, .visibility = aa32_id_visibility, .reset = read_sanitised_id_dfr0_el1, - .val = ID_DFR0_EL1_PerfMon_MASK | - ID_DFR0_EL1_CopDbg_MASK, }, + .val = GENMASK(31, 0) }, ID_HIDDEN(ID_AFR0_EL1), - AA32_ID_SANITISED(ID_MMFR0_EL1), - AA32_ID_SANITISED(ID_MMFR1_EL1), - AA32_ID_SANITISED(ID_MMFR2_EL1), - AA32_ID_SANITISED(ID_MMFR3_EL1), + AA32_ID_WRITABLE(ID_MMFR0_EL1), + AA32_ID_WRITABLE(ID_MMFR1_EL1), + AA32_ID_WRITABLE(ID_MMFR2_EL1), + AA32_ID_WRITABLE(ID_MMFR3_EL1), /* CRm=2 */ - AA32_ID_SANITISED(ID_ISAR0_EL1), - AA32_ID_SANITISED(ID_ISAR1_EL1), - AA32_ID_SANITISED(ID_ISAR2_EL1), - AA32_ID_SANITISED(ID_ISAR3_EL1), - AA32_ID_SANITISED(ID_ISAR4_EL1), - AA32_ID_SANITISED(ID_ISAR5_EL1), - AA32_ID_SANITISED(ID_MMFR4_EL1), - AA32_ID_SANITISED(ID_ISAR6_EL1), + AA32_ID_WRITABLE(ID_ISAR0_EL1), + AA32_ID_WRITABLE(ID_ISAR1_EL1), + AA32_ID_WRITABLE(ID_ISAR2_EL1), + AA32_ID_WRITABLE(ID_ISAR3_EL1), + AA32_ID_WRITABLE(ID_ISAR4_EL1), + AA32_ID_WRITABLE(ID_ISAR5_EL1), + AA32_ID_WRITABLE(ID_MMFR4_EL1), + AA32_ID_WRITABLE(ID_ISAR6_EL1), /* CRm=3 */ - AA32_ID_SANITISED(MVFR0_EL1), - AA32_ID_SANITISED(MVFR1_EL1), - AA32_ID_SANITISED(MVFR2_EL1), + AA32_ID_WRITABLE(MVFR0_EL1), + AA32_ID_WRITABLE(MVFR1_EL1), + AA32_ID_WRITABLE(MVFR2_EL1), ID_UNALLOCATED(3,3), - AA32_ID_SANITISED(ID_PFR2_EL1), + AA32_ID_WRITABLE(ID_PFR2_EL1), ID_HIDDEN(ID_DFR1_EL1), - AA32_ID_SANITISED(ID_MMFR5_EL1), + AA32_ID_WRITABLE(ID_MMFR5_EL1), ID_UNALLOCATED(3,7), /* AArch64 ID registers */ -- 2.47.3

1 week, 4 days

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[PATCH] can: rcar_canfd: Fix controller mode setting for RZ/G2L SoCs

by Biju

From: Biju Das <biju.das.jz(a)bp.renesas.com> The commit 5cff263606a1 ("can: rcar_canfd: Fix controller mode setting") applies to all SoCs except the RZ/G2L family of SoCs. As per RZ/G2L hardware manual "Figure 28.16 CAN Setting Procedure after the MCU is Reset" CAN mode needs to be set before channel reset. Add the mode_before_ch_rst variable to struct rcar_canfd_hw_info to handle this difference. The above commit also breaks CANFD functionality on RZ/G3E. Adapt this change to RZ/G3E, as well as it works ok by following the initialisation sequence of RZ/G2L. Fixes: 5cff263606a1 ("can: rcar_canfd: Fix controller mode setting") Cc: stable(a)vger.kernel.org Signed-off-by: Biju Das <biju.das.jz(a)bp.renesas.com> --- drivers/net/can/rcar/rcar_canfd.c | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-) diff --git a/drivers/net/can/rcar/rcar_canfd.c b/drivers/net/can/rcar/rcar_canfd.c index 49ab65274b51..1724fa5dace6 100644 --- a/drivers/net/can/rcar/rcar_canfd.c +++ b/drivers/net/can/rcar/rcar_canfd.c @@ -444,6 +444,7 @@ struct rcar_canfd_hw_info { unsigned ch_interface_mode:1; /* Has channel interface mode */ unsigned shared_can_regs:1; /* Has shared classical can registers */ unsigned external_clk:1; /* Has external clock */ + unsigned mode_before_ch_rst:1; /* Has set mode before channel reset */ }; /* Channel priv data */ @@ -615,6 +616,7 @@ static const struct rcar_canfd_hw_info rcar_gen3_hw_info = { .ch_interface_mode = 0, .shared_can_regs = 0, .external_clk = 1, + .mode_before_ch_rst = 0, }; static const struct rcar_canfd_hw_info rcar_gen4_hw_info = { @@ -632,6 +634,7 @@ static const struct rcar_canfd_hw_info rcar_gen4_hw_info = { .ch_interface_mode = 1, .shared_can_regs = 1, .external_clk = 1, + .mode_before_ch_rst = 0, }; static const struct rcar_canfd_hw_info rzg2l_hw_info = { @@ -649,6 +652,7 @@ static const struct rcar_canfd_hw_info rzg2l_hw_info = { .ch_interface_mode = 0, .shared_can_regs = 0, .external_clk = 1, + .mode_before_ch_rst = 1, }; static const struct rcar_canfd_hw_info r9a09g047_hw_info = { @@ -666,6 +670,7 @@ static const struct rcar_canfd_hw_info r9a09g047_hw_info = { .ch_interface_mode = 1, .shared_can_regs = 1, .external_clk = 0, + .mode_before_ch_rst = 1, }; /* Helper functions */ @@ -806,6 +811,10 @@ static int rcar_canfd_reset_controller(struct rcar_canfd_global *gpriv) /* Reset Global error flags */ rcar_canfd_write(gpriv->base, RCANFD_GERFL, 0x0); + /* RZ/G2L SoC needs setting the mode before channel reset */ + if (gpriv->info->mode_before_ch_rst) + rcar_canfd_set_mode(gpriv); + /* Transition all Channels to reset mode */ for_each_set_bit(ch, &gpriv->channels_mask, gpriv->info->max_channels) { rcar_canfd_clear_bit(gpriv->base, @@ -826,7 +835,8 @@ static int rcar_canfd_reset_controller(struct rcar_canfd_global *gpriv) } /* Set the controller into appropriate mode */ - rcar_canfd_set_mode(gpriv); + if (!gpriv->info->mode_before_ch_rst) + rcar_canfd_set_mode(gpriv); return 0; } -- 2.43.0

1 week, 4 days

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[PATCH 5.4.y] iommu/amd: Fix 2G+ memory-size overflow in unmap_sg()

by Jinhui Guo

Since npages is declared as int, shifting npages << PAGE_SHIFT for a 2 GB+ scatter-gather list overflows before reaching __unmap_single(), leading to incorrect unmapping. A 2 GB region equals 524,288 pages. The expression npages << PAGE_SHIFT yields 0x80000000, which exceeds INT32_MAX (0x7FFFFFFF). Casting to size_t therefore produces 0xFFFFFFFF80000000, an overflow value that breaks the unmap size calculation. Fix the overflow by casting npages to size_t before the PAGE_SHIFT left-shift. Fixes: 89736a0ee81d ("Revert "iommu/amd: Remove the leftover of bypass support"") Cc: stable(a)vger.kernel.org # 5.4 Signed-off-by: Jinhui Guo <guojinhui.liam(a)bytedance.com> --- Hi, We hit an IO_PAGE_FAULT on AMD with 5.4-stable when mapping a 2 GB scatter-gather list. The fault is caused by an overflow in unmap_sg(): on stable-5.4 the SG-mmap path was never moved to the IOMMU framework, so the bug exists only in this branch. Regards, Jinhui drivers/iommu/amd_iommu.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/iommu/amd_iommu.c b/drivers/iommu/amd_iommu.c index a30aac41af42..60872d7be52b 100644 --- a/drivers/iommu/amd_iommu.c +++ b/drivers/iommu/amd_iommu.c @@ -2682,7 +2682,7 @@ static void unmap_sg(struct device *dev, struct scatterlist *sglist, dma_dom = to_dma_ops_domain(domain); npages = sg_num_pages(dev, sglist, nelems); - __unmap_single(dma_dom, startaddr, npages << PAGE_SHIFT, dir); + __unmap_single(dma_dom, startaddr, (size_t)npages << PAGE_SHIFT, dir); } /* -- 2.20.1

1 week, 4 days

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[PATCH 1/3] KVM: arm64: Make ID_PFR1_EL1.GIC writable

by Marc Zyngier

Similarly to ID_AA64PFR0_EL1.GIC, relax ID_PFR1_EL1.GIC to be writable. Fixes: 5cb57a1aff755 ("KVM: arm64: Zero ID_AA64PFR0_EL1.GIC when no GICv3 is presented to the guest") Reported-by: Peter Maydell <peter.maydell(a)linaro.org> Signed-off-by: Marc Zyngier <maz(a)kernel.org> Cc: stable(a)vger.kernel.org --- arch/arm64/kvm/sys_regs.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c index b29f72478a50d..73dcefe51a3e7 100644 --- a/arch/arm64/kvm/sys_regs.c +++ b/arch/arm64/kvm/sys_regs.c @@ -2528,6 +2528,12 @@ static bool bad_redir_trap(struct kvm_vcpu *vcpu, .val = mask, \ } +#define AA32_ID_WRITABLE(name, mask) { \ + ID_DESC(name), \ + .visibility = aa32_id_visibility, \ + .val = mask, \ +} + /* sys_reg_desc initialiser for cpufeature ID registers that need filtering */ #define ID_FILTERED(sysreg, name, mask) { \ ID_DESC(sysreg), \ @@ -3040,7 +3046,7 @@ static const struct sys_reg_desc sys_reg_descs[] = { /* AArch64 mappings of the AArch32 ID registers */ /* CRm=1 */ AA32_ID_SANITISED(ID_PFR0_EL1), - AA32_ID_SANITISED(ID_PFR1_EL1), + AA32_ID_WRITABLE(ID_PFR1_EL1, ID_PFR1_EL1_GIC), { SYS_DESC(SYS_ID_DFR0_EL1), .access = access_id_reg, .get_user = get_id_reg, -- 2.47.3

1 week, 4 days

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