* [PATCH v5 0/5] ibmvfc: hard reset fixes
From: Tyrel Datwyler @ 2021-03-02 23:05 UTC (permalink / raw)
To: james.bottomley
Cc: Tyrel Datwyler, martin.petersen, linux-scsi, linux-kernel, brking,
linuxppc-dev
This series contains a minor simplification of ibmvfc_init_sub_crqs() followed
by a couple fixes for sub-CRQ handling which effect hard reset of the
client/host adapter CRQ pair.
changes in v5:
Patches 2-5: Corrected upstream commit ids for Fixes: tags
changes in v4:
Patch 2: dropped Reviewed-by tag and moved sub-crq init to after locked region
Patch 5: moved sub-crq init to after locked region
changes in v3:
* Patch 1 & 5: moved ibmvfc_init_sub_crqs out of locked patch
changes in v2:
* added Reviewed-by tags for patches 1-3
* Patch 4: use rtas_busy_delay to test rc and delay correct amount of time
* Patch 5: (new) similar fix for LPM case where CRQ pair needs re-enablement
Tyrel Datwyler (5):
powerpc/pseries: extract host bridge from pci_bus prior to bus removal
ibmvfc: simplify handling of sub-CRQ initialization
ibmvfc: fix invalid sub-CRQ handles after hard reset
ibmvfc: treat H_CLOSED as success during sub-CRQ registration
ibmvfc: store return code of H_FREE_SUB_CRQ during cleanup
arch/powerpc/platforms/pseries/pci_dlpar.c | 4 +-
drivers/scsi/ibmvscsi/ibmvfc.c | 49 ++++++++++------------
2 files changed, 26 insertions(+), 27 deletions(-)
--
2.27.0
^ permalink raw reply
* [PATCH v5 2/5] ibmvfc: fix invalid sub-CRQ handles after hard reset
From: Tyrel Datwyler @ 2021-03-02 23:05 UTC (permalink / raw)
To: james.bottomley
Cc: Tyrel Datwyler, martin.petersen, linux-scsi, linux-kernel, brking,
linuxppc-dev
In-Reply-To: <20210302230543.9905-1-tyreld@linux.ibm.com>
A hard reset results in a complete transport disconnect such that the
CRQ connection with the partner VIOS is broken. This has the side effect
of also invalidating the associated sub-CRQs. The current code assumes
that the sub-CRQs are perserved resulting in a protocol violation after
trying to reconnect them with the VIOS. This introduces an infinite loop
such that the VIOS forces a disconnect after each subsequent attempt to
re-register with invalid handles.
Avoid the aforementioned issue by releasing the sub-CRQs prior to CRQ
disconnect, and driving a reinitialization of the sub-CRQs once a new
CRQ is registered with the hypervisor.
fixes: 3034ebe26389 ("ibmvfc: add alloc/dealloc routines for SCSI Sub-CRQ Channels")
Signed-off-by: Tyrel Datwyler <tyreld@linux.ibm.com>
Reviewed-by: Brian King <brking@linux.ibm.com>
---
drivers/scsi/ibmvscsi/ibmvfc.c | 21 +++++++++------------
1 file changed, 9 insertions(+), 12 deletions(-)
diff --git a/drivers/scsi/ibmvscsi/ibmvfc.c b/drivers/scsi/ibmvscsi/ibmvfc.c
index 384960036f8b..d34e1a4f74d9 100644
--- a/drivers/scsi/ibmvscsi/ibmvfc.c
+++ b/drivers/scsi/ibmvscsi/ibmvfc.c
@@ -158,6 +158,9 @@ static void ibmvfc_npiv_logout(struct ibmvfc_host *);
static void ibmvfc_tgt_implicit_logout_and_del(struct ibmvfc_target *);
static void ibmvfc_tgt_move_login(struct ibmvfc_target *);
+static void ibmvfc_release_sub_crqs(struct ibmvfc_host *);
+static void ibmvfc_init_sub_crqs(struct ibmvfc_host *);
+
static const char *unknown_error = "unknown error";
static long h_reg_sub_crq(unsigned long unit_address, unsigned long ioba,
@@ -926,8 +929,8 @@ static int ibmvfc_reset_crq(struct ibmvfc_host *vhost)
unsigned long flags;
struct vio_dev *vdev = to_vio_dev(vhost->dev);
struct ibmvfc_queue *crq = &vhost->crq;
- struct ibmvfc_queue *scrq;
- int i;
+
+ ibmvfc_release_sub_crqs(vhost);
/* Close the CRQ */
do {
@@ -947,16 +950,6 @@ static int ibmvfc_reset_crq(struct ibmvfc_host *vhost)
memset(crq->msgs.crq, 0, PAGE_SIZE);
crq->cur = 0;
- if (vhost->scsi_scrqs.scrqs) {
- for (i = 0; i < nr_scsi_hw_queues; i++) {
- scrq = &vhost->scsi_scrqs.scrqs[i];
- spin_lock(scrq->q_lock);
- memset(scrq->msgs.scrq, 0, PAGE_SIZE);
- scrq->cur = 0;
- spin_unlock(scrq->q_lock);
- }
- }
-
/* And re-open it again */
rc = plpar_hcall_norets(H_REG_CRQ, vdev->unit_address,
crq->msg_token, PAGE_SIZE);
@@ -966,9 +959,12 @@ static int ibmvfc_reset_crq(struct ibmvfc_host *vhost)
dev_warn(vhost->dev, "Partner adapter not ready\n");
else if (rc != 0)
dev_warn(vhost->dev, "Couldn't register crq (rc=%d)\n", rc);
+
spin_unlock(vhost->crq.q_lock);
spin_unlock_irqrestore(vhost->host->host_lock, flags);
+ ibmvfc_init_sub_crqs(vhost);
+
return rc;
}
@@ -5692,6 +5688,7 @@ static void ibmvfc_deregister_scsi_channel(struct ibmvfc_host *vhost, int index)
free_irq(scrq->irq, scrq);
irq_dispose_mapping(scrq->irq);
+ scrq->irq = 0;
do {
rc = plpar_hcall_norets(H_FREE_SUB_CRQ, vdev->unit_address,
--
2.27.0
^ permalink raw reply related
* [PATCH v5 3/5] ibmvfc: treat H_CLOSED as success during sub-CRQ registration
From: Tyrel Datwyler @ 2021-03-02 23:05 UTC (permalink / raw)
To: james.bottomley
Cc: Tyrel Datwyler, martin.petersen, linux-scsi, linux-kernel, brking,
linuxppc-dev
In-Reply-To: <20210302230543.9905-1-tyreld@linux.ibm.com>
A non-zero return code for H_REG_SUB_CRQ is currently treated as a
failure resulting in failing sub-CRQ setup. The case of H_CLOSED should
not be treated as a failure. This return code translates to a successful
sub-CRQ registration by the hypervisor, and is meant to communicate back
that there is currently no partner VIOS CRQ connection established as of
yet. This is a common occurrence during a disconnect where the client
adapter can possibly come back up prior to the partner adapter.
For non-zero return code from H_REG_SUB_CRQ treat a H_CLOSED as success
so that sub-CRQs are successfully setup.
Fixes: 3034ebe26389 ("ibmvfc: add alloc/dealloc routines for SCSI Sub-CRQ Channels")
Signed-off-by: Tyrel Datwyler <tyreld@linux.ibm.com>
Reviewed-by: Brian King <brking@linux.ibm.com>
---
drivers/scsi/ibmvscsi/ibmvfc.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/drivers/scsi/ibmvscsi/ibmvfc.c b/drivers/scsi/ibmvscsi/ibmvfc.c
index d34e1a4f74d9..1d9f961715ca 100644
--- a/drivers/scsi/ibmvscsi/ibmvfc.c
+++ b/drivers/scsi/ibmvscsi/ibmvfc.c
@@ -5636,7 +5636,8 @@ static int ibmvfc_register_scsi_channel(struct ibmvfc_host *vhost,
rc = h_reg_sub_crq(vdev->unit_address, scrq->msg_token, PAGE_SIZE,
&scrq->cookie, &scrq->hw_irq);
- if (rc) {
+ /* H_CLOSED indicates successful register, but no CRQ partner */
+ if (rc && rc != H_CLOSED) {
dev_warn(dev, "Error registering sub-crq: %d\n", rc);
if (rc == H_PARAMETER)
dev_warn_once(dev, "Firmware may not support MQ\n");
--
2.27.0
^ permalink raw reply related
* Re: linux-next: build failure after merge of the powerpc-fixes tree
From: Michael Ellerman @ 2021-03-02 22:49 UTC (permalink / raw)
To: Uwe Kleine-König, Stephen Rothwell, PowerPC
Cc: Linux Next Mailing List, Linux Kernel Mailing List
In-Reply-To: <6113ab65-7b3c-07f0-2813-76ddaa4c7236@kleine-koenig.org>
Uwe Kleine-König <uwe@kleine-koenig.org> writes:
> Hello,
>
> On 3/2/21 3:09 AM, Michael Ellerman wrote:
>> Stephen Rothwell <sfr@canb.auug.org.au> writes:
>>> Hi all,
>>>
>>> After merging the powerpc-fixes tree, today's linux-next build (powerpc
>>> allyesconfig) failed like this:
>>>
>>> drivers/net/ethernet/ibm/ibmvnic.c:5399:13: error: conflicting types for 'ibmvnic_remove'
>>> 5399 | static void ibmvnic_remove(struct vio_dev *dev)
>>> | ^~~~~~~~~~~~~~
>>> drivers/net/ethernet/ibm/ibmvnic.c:81:12: note: previous declaration of 'ibmvnic_remove' was here
>>> 81 | static int ibmvnic_remove(struct vio_dev *);
>>> | ^~~~~~~~~~~~~~
>>>
>>> Caused by commit
>>>
>>> 1bdd1e6f9320 ("vio: make remove callback return void")
>>
>> Gah, is IBMVNIC in any of our defconfigs?! ... no it's not.
>
> Would you accept a patch to add the driver to one of the defconfigs as
> an excuse for the build breakage I created?
Thanks, but I already sent a patch adding it.
We should really have these drivers enabled in our defconfig, so that's
on us.
cheers
^ permalink raw reply
* Re: [PATCH v2 30/37] KVM: PPC: Book3S HV: Implement radix prefetch workaround by disabling MMU
From: Fabiano Rosas @ 2021-03-02 21:21 UTC (permalink / raw)
To: Nicholas Piggin, kvm-ppc; +Cc: linuxppc-dev, Nicholas Piggin
In-Reply-To: <20210225134652.2127648-31-npiggin@gmail.com>
Nicholas Piggin <npiggin@gmail.com> writes:
> Rather than partition the guest PID space and catch and flush a rogue
> guest, instead work around this issue by ensuring the MMU is always
> disabled in HV mode while the guest MMU context is switched in.
>
> This may be a bit less efficient, but it is a lot less complicated and
> allows the P9 path to trivally implement the workaround too. Newer CPUs
> are not subject to this issue.
>
> Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
> ---
> arch/powerpc/include/asm/mmu_context.h | 6 ----
> arch/powerpc/kvm/book3s_hv.c | 10 ++++--
> arch/powerpc/kvm/book3s_hv_interrupt.c | 14 ++++++--
> arch/powerpc/kvm/book3s_hv_rmhandlers.S | 34 ------------------
> arch/powerpc/mm/book3s64/radix_pgtable.c | 27 +++++---------
> arch/powerpc/mm/book3s64/radix_tlb.c | 46 ------------------------
> arch/powerpc/mm/mmu_context.c | 4 +--
> 7 files changed, 28 insertions(+), 113 deletions(-)
>
> diff --git a/arch/powerpc/include/asm/mmu_context.h b/arch/powerpc/include/asm/mmu_context.h
> index 652ce85f9410..bb5c7e5e142e 100644
> --- a/arch/powerpc/include/asm/mmu_context.h
> +++ b/arch/powerpc/include/asm/mmu_context.h
> @@ -122,12 +122,6 @@ static inline bool need_extra_context(struct mm_struct *mm, unsigned long ea)
> }
> #endif
>
> -#if defined(CONFIG_KVM_BOOK3S_HV_POSSIBLE) && defined(CONFIG_PPC_RADIX_MMU)
> -extern void radix_kvm_prefetch_workaround(struct mm_struct *mm);
> -#else
> -static inline void radix_kvm_prefetch_workaround(struct mm_struct *mm) { }
> -#endif
> -
> extern void switch_cop(struct mm_struct *next);
> extern int use_cop(unsigned long acop, struct mm_struct *mm);
> extern void drop_cop(unsigned long acop, struct mm_struct *mm);
> diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c
> index ad16331c3370..c3064075f1d7 100644
> --- a/arch/powerpc/kvm/book3s_hv.c
> +++ b/arch/powerpc/kvm/book3s_hv.c
> @@ -806,6 +806,10 @@ static int kvmppc_h_set_mode(struct kvm_vcpu *vcpu, unsigned long mflags,
> /* KVM does not support mflags=2 (AIL=2) */
> if (mflags != 0 && mflags != 3)
> return H_UNSUPPORTED_FLAG_START;
> + /* Prefetch bug */
> + if (cpu_has_feature(CPU_FTR_P9_RADIX_PREFETCH_BUG) &&
> + kvmhv_vcpu_is_radix(vcpu) && mflags == 3)
> + return H_UNSUPPORTED_FLAG_START;
So does this mean that if the host has the prefetch bug, all of its
guests will run with AIL=0 all the time? And what we're avoiding here is
a guest setting AIL=3 which would (since there's no HAIL) cause
hypervisor interrupts to be taken with MMU on, is that it?
Do we need to add this verification to kvmppc_set_lpcr as well? QEMU
could in theory call the KVM_SET_ONE_REG ioctl and set AIL to any value.
> return H_TOO_HARD;
> default:
> return H_TOO_HARD;
> @@ -4286,8 +4290,7 @@ static int kvmppc_vcpu_run_hv(struct kvm_vcpu *vcpu)
> * The TLB prefetch bug fixup is only in the kvmppc_run_vcpu
> * path, which also handles hash and dependent threads mode.
> */
> - if (kvm->arch.threads_indep && kvm_is_radix(kvm) &&
> - !cpu_has_feature(CPU_FTR_P9_RADIX_PREFETCH_BUG))
> + if (kvm->arch.threads_indep && kvm_is_radix(kvm))
> r = kvmhv_run_single_vcpu(vcpu, ~(u64)0,
> vcpu->arch.vcore->lpcr);
> else
> @@ -4914,6 +4917,9 @@ static int kvmppc_core_init_vm_hv(struct kvm *kvm)
> if (!indep_threads_mode && !cpu_has_feature(CPU_FTR_HVMODE)) {
> pr_warn("KVM: Ignoring indep_threads_mode=N in nested hypervisor\n");
> kvm->arch.threads_indep = true;
> + } else if (!indep_threads_mode && cpu_has_feature(CPU_FTR_P9_RADIX_PREFETCH_BUG)) {
> + pr_warn("KVM: Ignoring indep_threads_mode=N on pre-DD2.2 POWER9\n");
> + kvm->arch.threads_indep = true;
> } else {
> kvm->arch.threads_indep = indep_threads_mode;
> }
> diff --git a/arch/powerpc/kvm/book3s_hv_interrupt.c b/arch/powerpc/kvm/book3s_hv_interrupt.c
> index b93d861d8538..9784da3f8565 100644
> --- a/arch/powerpc/kvm/book3s_hv_interrupt.c
> +++ b/arch/powerpc/kvm/book3s_hv_interrupt.c
> @@ -223,6 +223,9 @@ int kvmhv_vcpu_entry_p9(struct kvm_vcpu *vcpu, u64 time_limit, unsigned long lpc
>
> mtspr(SPRN_AMOR, ~0UL);
>
> + if (cpu_has_feature(CPU_FTR_P9_RADIX_PREFETCH_BUG))
> + __mtmsrd(msr & ~(MSR_IR|MSR_DR|MSR_RI), 0);
> +
> switch_mmu_to_guest_radix(kvm, vcpu, lpcr);
>
> /*
> @@ -231,7 +234,8 @@ int kvmhv_vcpu_entry_p9(struct kvm_vcpu *vcpu, u64 time_limit, unsigned long lpc
> */
> mtspr(SPRN_HDEC, hdec);
>
> - __mtmsrd(0, 1); /* clear RI */
> + if (!cpu_has_feature(CPU_FTR_P9_RADIX_PREFETCH_BUG))
> + __mtmsrd(0, 1); /* clear RI */
>
> mtspr(SPRN_DAR, vcpu->arch.shregs.dar);
> mtspr(SPRN_DSISR, vcpu->arch.shregs.dsisr);
> @@ -338,8 +342,6 @@ int kvmhv_vcpu_entry_p9(struct kvm_vcpu *vcpu, u64 time_limit, unsigned long lpc
>
> radix_clear_slb();
>
> - __mtmsrd(msr, 0);
> -
> accumulate_time(vcpu, &vcpu->arch.rm_exit);
>
> /* Advance host PURR/SPURR by the amount used by guest */
> @@ -406,6 +408,12 @@ int kvmhv_vcpu_entry_p9(struct kvm_vcpu *vcpu, u64 time_limit, unsigned long lpc
>
> switch_mmu_to_host_radix(kvm, host_pidr);
>
> + /*
> + * If we are in real mode, don't switch MMU on until the MMU is
> + * switched to host, to avoid the P9 radix prefetch bug.
> + */
> + __mtmsrd(msr, 0);
> +
> end_timing(vcpu);
>
> return trap;
> diff --git a/arch/powerpc/kvm/book3s_hv_rmhandlers.S b/arch/powerpc/kvm/book3s_hv_rmhandlers.S
> index 6118e8a97ddd..61f71a7df238 100644
> --- a/arch/powerpc/kvm/book3s_hv_rmhandlers.S
> +++ b/arch/powerpc/kvm/book3s_hv_rmhandlers.S
> @@ -1710,40 +1710,6 @@ END_FTR_SECTION_IFSET(CPU_FTR_ARCH_300)
> eieio
> tlbsync
> ptesync
> -
> -BEGIN_FTR_SECTION
> - /* Radix: Handle the case where the guest used an illegal PID */
> - LOAD_REG_ADDR(r4, mmu_base_pid)
> - lwz r3, VCPU_GUEST_PID(r9)
> - lwz r5, 0(r4)
> - cmpw cr0,r3,r5
> - blt 2f
> -
> - /*
> - * Illegal PID, the HW might have prefetched and cached in the TLB
> - * some translations for the LPID 0 / guest PID combination which
> - * Linux doesn't know about, so we need to flush that PID out of
> - * the TLB. First we need to set LPIDR to 0 so tlbiel applies to
> - * the right context.
> - */
> - li r0,0
> - mtspr SPRN_LPID,r0
> - isync
> -
> - /* Then do a congruence class local flush */
> - ld r6,VCPU_KVM(r9)
> - lwz r0,KVM_TLB_SETS(r6)
> - mtctr r0
> - li r7,0x400 /* IS field = 0b01 */
> - ptesync
> - sldi r0,r3,32 /* RS has PID */
> -1: PPC_TLBIEL(7,0,2,1,1) /* RIC=2, PRS=1, R=1 */
> - addi r7,r7,0x1000
> - bdnz 1b
> - ptesync
> -END_FTR_SECTION_IFSET(CPU_FTR_P9_RADIX_PREFETCH_BUG)
> -
> -2:
> #endif /* CONFIG_PPC_RADIX_MMU */
>
> /*
> diff --git a/arch/powerpc/mm/book3s64/radix_pgtable.c b/arch/powerpc/mm/book3s64/radix_pgtable.c
> index 98f0b243c1ab..1ea95891a79e 100644
> --- a/arch/powerpc/mm/book3s64/radix_pgtable.c
> +++ b/arch/powerpc/mm/book3s64/radix_pgtable.c
> @@ -357,30 +357,19 @@ static void __init radix_init_pgtable(void)
> }
>
> /* Find out how many PID bits are supported */
> - if (!cpu_has_feature(CPU_FTR_P9_RADIX_PREFETCH_BUG)) {
> - if (!mmu_pid_bits)
> - mmu_pid_bits = 20;
> - mmu_base_pid = 1;
> - } else if (cpu_has_feature(CPU_FTR_HVMODE)) {
> - if (!mmu_pid_bits)
> - mmu_pid_bits = 20;
> -#ifdef CONFIG_KVM_BOOK3S_HV_POSSIBLE
> + if (!cpu_has_feature(CPU_FTR_HVMODE) &&
> + cpu_has_feature(CPU_FTR_P9_RADIX_PREFETCH_BUG)) {
> /*
> - * When KVM is possible, we only use the top half of the
> - * PID space to avoid collisions between host and guest PIDs
> - * which can cause problems due to prefetch when exiting the
> - * guest with AIL=3
> + * Older versions of KVM on these machines perfer if the
> + * guest only uses the low 19 PID bits.
> */
> - mmu_base_pid = 1 << (mmu_pid_bits - 1);
> -#else
> - mmu_base_pid = 1;
> -#endif
> - } else {
> - /* The guest uses the bottom half of the PID space */
> if (!mmu_pid_bits)
> mmu_pid_bits = 19;
> - mmu_base_pid = 1;
> + } else {
> + if (!mmu_pid_bits)
> + mmu_pid_bits = 20;
> }
> + mmu_base_pid = 1;
>
> /*
> * Allocate Partition table and process table for the
> diff --git a/arch/powerpc/mm/book3s64/radix_tlb.c b/arch/powerpc/mm/book3s64/radix_tlb.c
> index 409e61210789..312236a6b085 100644
> --- a/arch/powerpc/mm/book3s64/radix_tlb.c
> +++ b/arch/powerpc/mm/book3s64/radix_tlb.c
> @@ -1336,49 +1336,3 @@ void radix__flush_tlb_all(void)
> : : "r"(rb), "i"(r), "i"(prs), "i"(ric), "r"(0) : "memory");
> asm volatile("eieio; tlbsync; ptesync": : :"memory");
> }
> -
> -#ifdef CONFIG_KVM_BOOK3S_HV_POSSIBLE
> -extern void radix_kvm_prefetch_workaround(struct mm_struct *mm)
> -{
> - unsigned long pid = mm->context.id;
> -
> - if (unlikely(pid == MMU_NO_CONTEXT))
> - return;
> -
> - if (!cpu_has_feature(CPU_FTR_P9_RADIX_PREFETCH_BUG))
> - return;
> -
> - /*
> - * If this context hasn't run on that CPU before and KVM is
> - * around, there's a slim chance that the guest on another
> - * CPU just brought in obsolete translation into the TLB of
> - * this CPU due to a bad prefetch using the guest PID on
> - * the way into the hypervisor.
> - *
> - * We work around this here. If KVM is possible, we check if
> - * any sibling thread is in KVM. If it is, the window may exist
> - * and thus we flush that PID from the core.
> - *
> - * A potential future improvement would be to mark which PIDs
> - * have never been used on the system and avoid it if the PID
> - * is new and the process has no other cpumask bit set.
> - */
> - if (cpu_has_feature(CPU_FTR_HVMODE) && radix_enabled()) {
> - int cpu = smp_processor_id();
> - int sib = cpu_first_thread_sibling(cpu);
> - bool flush = false;
> -
> - for (; sib <= cpu_last_thread_sibling(cpu) && !flush; sib++) {
> - if (sib == cpu)
> - continue;
> - if (!cpu_possible(sib))
> - continue;
> - if (paca_ptrs[sib]->kvm_hstate.kvm_vcpu)
> - flush = true;
> - }
> - if (flush)
> - _tlbiel_pid(pid, RIC_FLUSH_ALL);
> - }
> -}
> -EXPORT_SYMBOL_GPL(radix_kvm_prefetch_workaround);
> -#endif /* CONFIG_KVM_BOOK3S_HV_POSSIBLE */
> diff --git a/arch/powerpc/mm/mmu_context.c b/arch/powerpc/mm/mmu_context.c
> index 18f20da0d348..7479d39976c9 100644
> --- a/arch/powerpc/mm/mmu_context.c
> +++ b/arch/powerpc/mm/mmu_context.c
> @@ -81,9 +81,7 @@ void switch_mm_irqs_off(struct mm_struct *prev, struct mm_struct *next,
> if (cpu_has_feature(CPU_FTR_ALTIVEC))
> asm volatile ("dssall");
>
> - if (new_on_cpu)
> - radix_kvm_prefetch_workaround(next);
> - else
> + if (!new_on_cpu)
> membarrier_arch_switch_mm(prev, next, tsk);
>
> /*
^ permalink raw reply
* Re: [PATCH] ibmvnic: Fix possibly uninitialized old_num_tx_queues variable warning.
From: Sukadev Bhattiprolu @ 2021-03-02 20:55 UTC (permalink / raw)
To: Michal Suchanek
Cc: netdev, linux-kernel, Jakub Kicinski, Lijun Pan, Dany Madden,
Paul Mackerras, linuxppc-dev, David S. Miller
In-Reply-To: <20210302194747.21704-1-msuchanek@suse.de>
Michal Suchanek [msuchanek@suse.de] wrote:
> GCC 7.5 reports:
> ../drivers/net/ethernet/ibm/ibmvnic.c: In function 'ibmvnic_reset_init':
> ../drivers/net/ethernet/ibm/ibmvnic.c:5373:51: warning: 'old_num_tx_queues' may be used uninitialized in this function [-Wmaybe-uninitialized]
> ../drivers/net/ethernet/ibm/ibmvnic.c:5373:6: warning: 'old_num_rx_queues' may be used uninitialized in this function [-Wmaybe-uninitialized]
>
> The variable is initialized only if(reset) and used only if(reset &&
> something) so this is a false positive. However, there is no reason to
> not initialize the variables unconditionally avoiding the warning.
Yeah, its a false positive, but initializing doesn't hurt.
>
> Fixes: 635e442f4a48 ("ibmvnic: merge ibmvnic_reset_init and ibmvnic_init")
> Signed-off-by: Michal Suchanek <msuchanek@suse.de>
Reviewed-by: Sukadev Bhattiprolu <sukadev@linux.ibm.com>
^ permalink raw reply
* Re: Build regressions/improvements in v5.12-rc1
From: Geert Uytterhoeven @ 2021-03-02 20:01 UTC (permalink / raw)
To: Alex Deucher
Cc: Alex Deucher, linuxppc-dev, LKML, amd-gfx list,
Christian König
In-Reply-To: <CADnq5_O-j8EWL+Eb8zK-7WqUuWKWETVWYRQNFdS_ymUSgo1jrg@mail.gmail.com>
Hi Alex,
On Tue, Mar 2, 2021 at 8:30 PM Alex Deucher <alexdeucher@gmail.com> wrote:
> On Mon, Mar 1, 2021 at 9:21 AM Geert Uytterhoeven <geert@linux-m68k.org> wrote:
> > On Mon, 1 Mar 2021, Geert Uytterhoeven wrote:
> > > Below is the list of build error/warning regressions/improvements in
> > > v5.12-rc1[1] compared to v5.11[2].
> > >
> > > Summarized:
> > > - build errors: +2/-0
> >
> > > [1] http://kisskb.ellerman.id.au/kisskb/branch/linus/head/fe07bfda2fb9cdef8a4d4008a409bb02f35f1bd8/ (all 192 configs)
> > > [2] http://kisskb.ellerman.id.au/kisskb/branch/linus/head/f40ddce88593482919761f74910f42f4b84c004b/ (all 192 configs)
> > >
> > >
> > > *** ERRORS ***
> > >
> > > 2 error regressions:
> > > + /kisskb/src/drivers/gpu/drm/amd/amdgpu/../display/dc/calcs/dcn_calcs.c: error: implicit declaration of function 'disable_kernel_vsx' [-Werror=implicit-function-declaration]: => 674:2
> > > + /kisskb/src/drivers/gpu/drm/amd/amdgpu/../display/dc/calcs/dcn_calcs.c: error: implicit declaration of function 'enable_kernel_vsx' [-Werror=implicit-function-declaration]: => 638:2
> >
> > powerpc-gcc4.9/ppc64_book3e_allmodconfig
> >
> > This was fixed in v5.11-rc1, but reappeared in v5.12-rc1?
>
> Do you know what fixed in for 5.11? I guess for PPC64 we depend on CONFIG_VSX?
Looking at the kisskb build logs for v5.11*, it seems compilation never
got to drivers/gpu/drm/ due to internal compiler errors that weren't caught
by my scripts. So the errors listed above were not really fixed.
Gr{oetje,eeting}s,
Geert
--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org
In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds
^ permalink raw reply
* [PATCH] ibmvnic: Fix possibly uninitialized old_num_tx_queues variable warning.
From: Michal Suchanek @ 2021-03-02 19:47 UTC (permalink / raw)
To: netdev
Cc: Sukadev Bhattiprolu, linux-kernel, Jakub Kicinski, Lijun Pan,
Dany Madden, Paul Mackerras, Michal Suchanek, linuxppc-dev,
David S. Miller
GCC 7.5 reports:
../drivers/net/ethernet/ibm/ibmvnic.c: In function 'ibmvnic_reset_init':
../drivers/net/ethernet/ibm/ibmvnic.c:5373:51: warning: 'old_num_tx_queues' may be used uninitialized in this function [-Wmaybe-uninitialized]
../drivers/net/ethernet/ibm/ibmvnic.c:5373:6: warning: 'old_num_rx_queues' may be used uninitialized in this function [-Wmaybe-uninitialized]
The variable is initialized only if(reset) and used only if(reset &&
something) so this is a false positive. However, there is no reason to
not initialize the variables unconditionally avoiding the warning.
Fixes: 635e442f4a48 ("ibmvnic: merge ibmvnic_reset_init and ibmvnic_init")
Signed-off-by: Michal Suchanek <msuchanek@suse.de>
---
drivers/net/ethernet/ibm/ibmvnic.c | 8 +++-----
1 file changed, 3 insertions(+), 5 deletions(-)
diff --git a/drivers/net/ethernet/ibm/ibmvnic.c b/drivers/net/ethernet/ibm/ibmvnic.c
index 118a4bd3f877..3bad762083c5 100644
--- a/drivers/net/ethernet/ibm/ibmvnic.c
+++ b/drivers/net/ethernet/ibm/ibmvnic.c
@@ -5219,16 +5219,14 @@ static int ibmvnic_reset_init(struct ibmvnic_adapter *adapter, bool reset)
{
struct device *dev = &adapter->vdev->dev;
unsigned long timeout = msecs_to_jiffies(20000);
- u64 old_num_rx_queues, old_num_tx_queues;
+ u64 old_num_rx_queues = adapter->req_rx_queues;
+ u64 old_num_tx_queues = adapter->req_tx_queues;
int rc;
adapter->from_passive_init = false;
- if (reset) {
- old_num_rx_queues = adapter->req_rx_queues;
- old_num_tx_queues = adapter->req_tx_queues;
+ if (reset)
reinit_completion(&adapter->init_done);
- }
adapter->init_done_rc = 0;
rc = ibmvnic_send_crq_init(adapter);
--
2.26.2
^ permalink raw reply related
* Re: [PATCH v2 6/7] cmdline: Gives architectures opportunity to use generically defined boot cmdline manipulation
From: kernel test robot @ 2021-03-02 19:30 UTC (permalink / raw)
To: Christophe Leroy, Benjamin Herrenschmidt, Paul Mackerras,
Michael Ellerman, danielwa, robh, daniel
Cc: linux-arch, devicetree, kbuild-all, linuxppc-dev, linux-kernel
In-Reply-To: <2eb6fad3470256fff5c9f33cd876f344abb1628b.1614705851.git.christophe.leroy@csgroup.eu>
[-- Attachment #1: Type: text/plain, Size: 3721 bytes --]
Hi Christophe,
I love your patch! Yet something to improve:
[auto build test ERROR on powerpc/next]
[also build test ERROR on robh/for-next linus/master v5.12-rc1 next-20210302]
[cannot apply to mpe/next]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch]
url: https://github.com/0day-ci/linux/commits/Christophe-Leroy/Improve-boot-command-line-handling/20210303-014039
base: https://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux.git next
config: sh-randconfig-s031-20210302 (attached as .config)
compiler: sh4-linux-gcc (GCC) 9.3.0
reproduce:
wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# apt-get install sparse
# sparse version: v0.6.3-241-geaceeafa-dirty
# https://github.com/0day-ci/linux/commit/edc3f8320d1dcb21a71e4cfdb26a3d2b64215c30
git remote add linux-review https://github.com/0day-ci/linux
git fetch --no-tags linux-review Christophe-Leroy/Improve-boot-command-line-handling/20210303-014039
git checkout edc3f8320d1dcb21a71e4cfdb26a3d2b64215c30
# save the attached .config to linux build tree
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross C=1 CF='-fdiagnostic-prefix -D__CHECK_ENDIAN__' ARCH=sh
If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>
All errors (new ones prefixed by >>):
arch/sh/Kconfig:760:warning: choice value used outside its choice group
>> init/Kconfig:142:error: recursive dependency detected!
init/Kconfig:142: choice <choice> contains symbol CMDLINE
init/Kconfig:132: symbol CMDLINE depends on CMDLINE_EXTEND
init/Kconfig:155: symbol CMDLINE_EXTEND is part of choice <choice>
For a resolution refer to Documentation/kbuild/kconfig-language.rst
subsection "Kconfig recursive dependency limitations"
vim +142 init/Kconfig
103
104 config BROKEN
105 bool
106
107 config BROKEN_ON_SMP
108 bool
109 depends on BROKEN || !SMP
110 default y
111
112 config INIT_ENV_ARG_LIMIT
113 int
114 default 32 if !UML
115 default 128 if UML
116 help
117 Maximum of each of the number of arguments and environment
118 variables passed to init from the kernel command line.
119
120 config HAVE_CMDLINE
121 bool
122
123 config CMDLINE_BOOL
124 bool "Default bootloader kernel arguments"
125 depends on HAVE_CMDLINE
126 help
127 On some platforms, there is currently no way for the boot loader to
128 pass arguments to the kernel. For these platforms, you can supply
129 some command-line options at build time by entering them here. In
130 most cases you will need to specify the root device here.
131
132 config CMDLINE
133 string "Initial kernel command string"
134 depends on CMDLINE_BOOL
135 default DEFAULT_CMDLINE
136 help
137 On some platforms, there is currently no way for the boot loader to
138 pass arguments to the kernel. For these platforms, you can supply
139 some command-line options at build time by entering them here. In
140 most cases you will need to specify the root device here.
141
> 142 choice
143 prompt "Kernel command line type" if CMDLINE != ""
144 default CMDLINE_FROM_BOOTLOADER
145 help
146 Selects the way you want to use the default kernel arguments.
147
---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org
[-- Attachment #2: .config.gz --]
[-- Type: application/gzip, Size: 30198 bytes --]
^ permalink raw reply
* Re: Build regressions/improvements in v5.12-rc1
From: Alex Deucher @ 2021-03-02 19:30 UTC (permalink / raw)
To: Geert Uytterhoeven
Cc: Alex Deucher, linuxppc-dev, LKML, amd-gfx list,
Christian König
In-Reply-To: <alpine.DEB.2.22.394.2103011342520.710098@ramsan.of.borg>
On Mon, Mar 1, 2021 at 9:21 AM Geert Uytterhoeven <geert@linux-m68k.org> wrote:
>
> On Mon, 1 Mar 2021, Geert Uytterhoeven wrote:
> > Below is the list of build error/warning regressions/improvements in
> > v5.12-rc1[1] compared to v5.11[2].
> >
> > Summarized:
> > - build errors: +2/-0
>
> > [1] http://kisskb.ellerman.id.au/kisskb/branch/linus/head/fe07bfda2fb9cdef8a4d4008a409bb02f35f1bd8/ (all 192 configs)
> > [2] http://kisskb.ellerman.id.au/kisskb/branch/linus/head/f40ddce88593482919761f74910f42f4b84c004b/ (all 192 configs)
> >
> >
> > *** ERRORS ***
> >
> > 2 error regressions:
> > + /kisskb/src/drivers/gpu/drm/amd/amdgpu/../display/dc/calcs/dcn_calcs.c: error: implicit declaration of function 'disable_kernel_vsx' [-Werror=implicit-function-declaration]: => 674:2
> > + /kisskb/src/drivers/gpu/drm/amd/amdgpu/../display/dc/calcs/dcn_calcs.c: error: implicit declaration of function 'enable_kernel_vsx' [-Werror=implicit-function-declaration]: => 638:2
>
> powerpc-gcc4.9/ppc64_book3e_allmodconfig
>
> This was fixed in v5.11-rc1, but reappeared in v5.12-rc1?
Do you know what fixed in for 5.11? I guess for PPC64 we depend on CONFIG_VSX?
Alex
>
> Gr{oetje,eeting}s,
>
> Geert
>
> --
> Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org
>
> In personal conversations with technical people, I call myself a hacker. But
> when I'm talking to journalists I just say "programmer" or something like that.
> -- Linus Torvalds
> _______________________________________________
> amd-gfx mailing list
> amd-gfx@lists.freedesktop.org
> https://lists.freedesktop.org/mailman/listinfo/amd-gfx
^ permalink raw reply
* Re: [PATCH 40/44] tty: hvc, drop unneeded forward declarations
From: Tyrel Datwyler @ 2021-03-02 19:09 UTC (permalink / raw)
To: Jiri Slaby, gregkh; +Cc: linuxppc-dev, linux-kernel, linux-serial
In-Reply-To: <20210302062214.29627-40-jslaby@suse.cz>
On 3/1/21 10:22 PM, Jiri Slaby wrote:
> Forward declarations make the code larger and rewrites harder. Harder as
> they are often omitted from global changes. Remove forward declarations
> which are not really needed, i.e. the definition of the function is
> before its first use.
>
> Signed-off-by: Jiri Slaby <jslaby@suse.cz>
> Cc: linuxppc-dev@lists.ozlabs.org
Reviewed-by: Tyrel Datwyler <tyreld@linux.ibm.com>
> ---
> drivers/tty/hvc/hvcs.c | 25 -------------------------
> 1 file changed, 25 deletions(-)
>
> diff --git a/drivers/tty/hvc/hvcs.c b/drivers/tty/hvc/hvcs.c
> index c90848919644..0b89d878a108 100644
> --- a/drivers/tty/hvc/hvcs.c
> +++ b/drivers/tty/hvc/hvcs.c
> @@ -290,36 +290,11 @@ static LIST_HEAD(hvcs_structs);
> static DEFINE_SPINLOCK(hvcs_structs_lock);
> static DEFINE_MUTEX(hvcs_init_mutex);
>
> -static void hvcs_unthrottle(struct tty_struct *tty);
> -static void hvcs_throttle(struct tty_struct *tty);
> -static irqreturn_t hvcs_handle_interrupt(int irq, void *dev_instance);
> -
> -static int hvcs_write(struct tty_struct *tty,
> - const unsigned char *buf, int count);
> -static int hvcs_write_room(struct tty_struct *tty);
> -static int hvcs_chars_in_buffer(struct tty_struct *tty);
> -
> -static int hvcs_has_pi(struct hvcs_struct *hvcsd);
> -static void hvcs_set_pi(struct hvcs_partner_info *pi,
> - struct hvcs_struct *hvcsd);
> static int hvcs_get_pi(struct hvcs_struct *hvcsd);
> static int hvcs_rescan_devices_list(void);
>
> -static int hvcs_partner_connect(struct hvcs_struct *hvcsd);
> static void hvcs_partner_free(struct hvcs_struct *hvcsd);
>
> -static int hvcs_enable_device(struct hvcs_struct *hvcsd,
> - uint32_t unit_address, unsigned int irq, struct vio_dev *dev);
> -
> -static int hvcs_open(struct tty_struct *tty, struct file *filp);
> -static void hvcs_close(struct tty_struct *tty, struct file *filp);
> -static void hvcs_hangup(struct tty_struct * tty);
> -
> -static int hvcs_probe(struct vio_dev *dev,
> - const struct vio_device_id *id);
> -static int hvcs_remove(struct vio_dev *dev);
> -static int __init hvcs_module_init(void);
> -static void __exit hvcs_module_exit(void);
> static int hvcs_initialize(void);
>
> #define HVCS_SCHED_READ 0x00000001
>
^ permalink raw reply
* Re: [RFC PATCH v1] powerpc: Enable KFENCE for PPC32
From: Segher Boessenkool @ 2021-03-02 18:48 UTC (permalink / raw)
To: Michael Ellerman
Cc: Marco Elver, LKML, kasan-dev, Paul Mackerras, Alexander Potapenko,
linuxppc-dev, Dmitry Vyukov
In-Reply-To: <87h7ltss18.fsf@mpe.ellerman.id.au>
On Tue, Mar 02, 2021 at 10:40:03PM +1100, Michael Ellerman wrote:
> >> -- Change the unwinder, if it's possible for ppc32.
> >
> > I don't think it is possible.
>
> I think this actually is the solution.
>
> It seems the good architectures have all added support for
> arch_stack_walk(), and we have not.
I have no idea what arch_stack_walk does, but some background info:
PowerPC functions that do save the LR (== the return address), and/or
that set up a new stack frame, do not do this at the start of the
function necessarily (it is a lot faster to postpone this, even if you
always have to do it). So, in a leaf function it isn't always known if
this has been done (in all callers further up it is always done, of
course). If you have DWARF unwind info all is fine of course, but you
do not have that in the kernel.
> So I think it's probably on us to update to that new API. Or at least
> update our save_stack_trace() to fabricate an entry using the NIP, as it
> seems that's what callers expect.
This sounds very expensive? If it is only a debug feature that won't
be used in production that does not matter, but it worries me.
Segher
^ permalink raw reply
* Re: [PATCH v2 0/7] Improve boot command line handling
From: Christophe Leroy @ 2021-03-02 17:39 UTC (permalink / raw)
To: Daniel Walker
Cc: linux-arch, robh, daniel, devicetree, linux-kernel,
Paul Mackerras, linuxppc-dev
In-Reply-To: <20210302173523.GE109100@zorba>
Le 02/03/2021 à 18:35, Daniel Walker a écrit :
> On Tue, Mar 02, 2021 at 05:25:16PM +0000, Christophe Leroy wrote:
>> The purpose of this series is to improve and enhance the
>> handling of kernel boot arguments.
>>
>> It is first focussed on powerpc but also extends the capability
>> for other arches.
>>
>> This is based on suggestion from Daniel Walker <danielwa@cisco.com>
>>
>
>
> I don't see a point in your changes at this time. My changes are much more
> mature, and you changes don't really make improvements.
>
Cool, I'm eager to see them.
Christophe
^ permalink raw reply
* Re: [PATCH v2 0/7] Improve boot command line handling
From: Daniel Walker @ 2021-03-02 17:35 UTC (permalink / raw)
To: Christophe Leroy
Cc: linux-arch, robh, daniel, devicetree, linux-kernel,
Paul Mackerras, linuxppc-dev
In-Reply-To: <cover.1614705851.git.christophe.leroy@csgroup.eu>
On Tue, Mar 02, 2021 at 05:25:16PM +0000, Christophe Leroy wrote:
> The purpose of this series is to improve and enhance the
> handling of kernel boot arguments.
>
> It is first focussed on powerpc but also extends the capability
> for other arches.
>
> This is based on suggestion from Daniel Walker <danielwa@cisco.com>
>
I don't see a point in your changes at this time. My changes are much more
mature, and you changes don't really make improvements.
Daniel
^ permalink raw reply
* [PATCH v2 7/7] powerpc: use generic CMDLINE manipulations
From: Christophe Leroy @ 2021-03-02 17:25 UTC (permalink / raw)
To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman,
danielwa, robh, daniel
Cc: linux-arch, devicetree, linuxppc-dev, linux-kernel
In-Reply-To: <cover.1614705851.git.christophe.leroy@csgroup.eu>
This patch moves powerpc to the centraly defined CMDLINE options.
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
arch/powerpc/Kconfig | 43 +++----------------------------------------
1 file changed, 3 insertions(+), 40 deletions(-)
diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index 0ab406f14513..0e1736a2a621 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -195,6 +195,7 @@ config PPC
select HAVE_CBPF_JIT if !PPC64
select HAVE_STACKPROTECTOR if PPC64 && $(cc-option,-mstack-protector-guard=tls -mstack-protector-guard-reg=r13)
select HAVE_STACKPROTECTOR if PPC32 && $(cc-option,-mstack-protector-guard=tls -mstack-protector-guard-reg=r2)
+ select HAVE_CMDLINE
select HAVE_CONTEXT_TRACKING if PPC64
select HAVE_DEBUG_KMEMLEAK
select HAVE_DEBUG_STACKOVERFLOW
@@ -886,47 +887,9 @@ config PPC_DENORMALISATION
Add support for handling denormalisation of single precision
values. Useful for bare metal only. If unsure say Y here.
-config CMDLINE
- string "Initial kernel command string"
+config DEFAULT_CMDLINE
+ string
default ""
- help
- On some platforms, there is currently no way for the boot loader to
- pass arguments to the kernel. For these platforms, you can supply
- some command-line options at build time by entering them here. In
- most cases you will need to specify the root device here.
-
-choice
- prompt "Kernel command line type" if CMDLINE != ""
- default CMDLINE_FROM_BOOTLOADER
-
-config CMDLINE_FROM_BOOTLOADER
- bool "Use bootloader kernel arguments if available"
- help
- Uses the command-line options passed by the boot loader. If
- the boot loader doesn't provide any, the default kernel command
- string provided in CMDLINE will be used.
-
-config CMDLINE_EXTEND
- bool "Extend bootloader kernel arguments"
- help
- The command-line arguments provided by the boot loader will be
- appended to the default kernel command string.
-
-config CMDLINE_PREPEND
- bool "Prepend bootloader kernel arguments"
- help
- The default kernel command string will be prepend to the
- command-line arguments provided during boot.
-
-config CMDLINE_FORCE
- bool "Always use the default kernel command string"
- help
- Always use the default kernel command string, even if the boot
- loader passes other arguments to the kernel.
- This is useful if you cannot or don't want to change the
- command-line options your boot loader passes to the kernel.
-
-endchoice
config EXTRA_TARGETS
string "Additional default image types"
--
2.25.0
^ permalink raw reply related
* [PATCH v2 6/7] cmdline: Gives architectures opportunity to use generically defined boot cmdline manipulation
From: Christophe Leroy @ 2021-03-02 17:25 UTC (permalink / raw)
To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman,
danielwa, robh, daniel
Cc: linux-arch, devicetree, linuxppc-dev, linux-kernel
In-Reply-To: <cover.1614705851.git.christophe.leroy@csgroup.eu>
Most architectures have similar boot command line manipulation
options. This patchs adds the definition in init/Kconfig, gated by
CONFIG_HAVE_CMDLINE that the architectures can select to use them.
In order to use this, a few architectures will have to change their
CONFIG options:
- riscv has to replace CMDLINE_FALLBACK by CMDLINE_FROM_BOOTLOADER
- architectures using CONFIG_CMDLINE_OVERRIDE or
CONFIG_CMDLINE_OVERWRITE have to replace them by CONFIG_CMDLINE_FORCE.
Architectures also have to define CONFIG_DEFAULT_CMDLINE.
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
init/Kconfig | 56 ++++++++++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 56 insertions(+)
diff --git a/init/Kconfig b/init/Kconfig
index 22946fe5ded9..a0f2ad9467df 100644
--- a/init/Kconfig
+++ b/init/Kconfig
@@ -117,6 +117,62 @@ config INIT_ENV_ARG_LIMIT
Maximum of each of the number of arguments and environment
variables passed to init from the kernel command line.
+config HAVE_CMDLINE
+ bool
+
+config CMDLINE_BOOL
+ bool "Default bootloader kernel arguments"
+ depends on HAVE_CMDLINE
+ help
+ On some platforms, there is currently no way for the boot loader to
+ pass arguments to the kernel. For these platforms, you can supply
+ some command-line options at build time by entering them here. In
+ most cases you will need to specify the root device here.
+
+config CMDLINE
+ string "Initial kernel command string"
+ depends on CMDLINE_BOOL
+ default DEFAULT_CMDLINE
+ help
+ On some platforms, there is currently no way for the boot loader to
+ pass arguments to the kernel. For these platforms, you can supply
+ some command-line options at build time by entering them here. In
+ most cases you will need to specify the root device here.
+
+choice
+ prompt "Kernel command line type" if CMDLINE != ""
+ default CMDLINE_FROM_BOOTLOADER
+ help
+ Selects the way you want to use the default kernel arguments.
+
+config CMDLINE_FROM_BOOTLOADER
+ bool "Use bootloader kernel arguments if available"
+ help
+ Uses the command-line options passed by the boot loader. If
+ the boot loader doesn't provide any, the default kernel command
+ string provided in CMDLINE will be used.
+
+config CMDLINE_EXTEND
+ bool "Extend bootloader kernel arguments"
+ help
+ The default kernel command string will be appended to the
+ command-line arguments provided during boot.
+
+config CMDLINE_PREPEND
+ bool "Prepend bootloader kernel arguments"
+ help
+ The default kernel command string will be prepend to the
+ command-line arguments provided during boot.
+
+config CMDLINE_FORCE
+ bool "Always use the default kernel command string"
+ help
+ Always use the default kernel command string, even if the boot
+ loader passes other arguments to the kernel.
+ This is useful if you cannot or don't want to change the
+ command-line options your boot loader passes to the kernel.
+endchoice
+
config COMPILE_TEST
bool "Compile also drivers which will not load"
depends on !UML && !S390
--
2.25.0
^ permalink raw reply related
* [PATCH v2 5/7] powerpc: add capability to prepend default command line
From: Christophe Leroy @ 2021-03-02 17:25 UTC (permalink / raw)
To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman,
danielwa, robh, daniel
Cc: linux-arch, devicetree, linuxppc-dev, linux-kernel
In-Reply-To: <cover.1614705851.git.christophe.leroy@csgroup.eu>
This patch activates the capability to prepend default
arguments to the command line.
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
arch/powerpc/Kconfig | 6 ++++++
1 file changed, 6 insertions(+)
diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index 386ae12d8523..0ab406f14513 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -912,6 +912,12 @@ config CMDLINE_EXTEND
The command-line arguments provided by the boot loader will be
appended to the default kernel command string.
+config CMDLINE_PREPEND
+ bool "Prepend bootloader kernel arguments"
+ help
+ The default kernel command string will be prepend to the
+ command-line arguments provided during boot.
+
config CMDLINE_FORCE
bool "Always use the default kernel command string"
help
--
2.25.0
^ permalink raw reply related
* [PATCH v2 3/7] powerpc: convert to generic builtin command line
From: Christophe Leroy @ 2021-03-02 17:25 UTC (permalink / raw)
To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman,
danielwa, robh, daniel
Cc: linux-arch, devicetree, linuxppc-dev, linux-kernel
In-Reply-To: <cover.1614705851.git.christophe.leroy@csgroup.eu>
This updates the powerpc code to use the new cmdline building function.
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
arch/powerpc/kernel/prom_init.c | 35 +++++----------------------------
1 file changed, 5 insertions(+), 30 deletions(-)
diff --git a/arch/powerpc/kernel/prom_init.c b/arch/powerpc/kernel/prom_init.c
index ccf77b985c8f..24157e526f80 100644
--- a/arch/powerpc/kernel/prom_init.c
+++ b/arch/powerpc/kernel/prom_init.c
@@ -27,6 +27,7 @@
#include <linux/initrd.h>
#include <linux/bitops.h>
#include <linux/pgtable.h>
+#include <linux/cmdline.h>
#include <asm/prom.h>
#include <asm/rtas.h>
#include <asm/page.h>
@@ -152,7 +153,7 @@ static struct prom_t __prombss prom;
static unsigned long __prombss prom_entry;
static char __prombss of_stdout_device[256];
-static char __prombss prom_scratch[256];
+static char __prombss prom_scratch[COMMAND_LINE_SIZE];
static unsigned long __prombss dt_header_start;
static unsigned long __prombss dt_struct_start, dt_struct_end;
@@ -304,26 +305,6 @@ static char __init *prom_strstr(const char *s1, const char *s2)
return NULL;
}
-static size_t __init prom_strlcat(char *dest, const char *src, size_t count)
-{
- size_t dsize = prom_strlen(dest);
- size_t len = prom_strlen(src);
- size_t res = dsize + len;
-
- /* This would be a bug */
- if (dsize >= count)
- return count;
-
- dest += dsize;
- count -= dsize;
- if (len >= count)
- len = count-1;
- memcpy(dest, src, len);
- dest[len] = 0;
- return res;
-
-}
-
#ifdef CONFIG_PPC_PSERIES
static int __init prom_strtobool(const char *s, bool *res)
{
@@ -768,19 +749,13 @@ static unsigned long prom_memparse(const char *ptr, const char **retptr)
static void __init early_cmdline_parse(void)
{
const char *opt;
-
- char *p;
int l = 0;
- prom_cmd_line[0] = 0;
- p = prom_cmd_line;
-
if (!IS_ENABLED(CONFIG_CMDLINE_FORCE) && (long)prom.chosen > 0)
- l = prom_getprop(prom.chosen, "bootargs", p, COMMAND_LINE_SIZE-1);
+ l = prom_getprop(prom.chosen, "bootargs", prom_scratch,
+ COMMAND_LINE_SIZE - 1);
- if (IS_ENABLED(CONFIG_CMDLINE_EXTEND) || l <= 0 || p[0] == '\0')
- prom_strlcat(prom_cmd_line, " " CONFIG_CMDLINE,
- sizeof(prom_cmd_line));
+ cmdline_build(prom_cmd_line, l > 0 ? prom_scratch : NULL, sizeof(prom_scratch));
prom_printf("command line: %s\n", prom_cmd_line);
--
2.25.0
^ permalink raw reply related
* [PATCH v2 4/7] cmdline: Add capability to prepend the command line
From: Christophe Leroy @ 2021-03-02 17:25 UTC (permalink / raw)
To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman,
danielwa, robh, daniel
Cc: linux-arch, devicetree, linuxppc-dev, linux-kernel
In-Reply-To: <cover.1614705851.git.christophe.leroy@csgroup.eu>
This patchs adds an option of prepend a text to the command
line instead of appending it.
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
include/linux/cmdline.h | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)
diff --git a/include/linux/cmdline.h b/include/linux/cmdline.h
index ae3610bb0ee2..144346051e01 100644
--- a/include/linux/cmdline.h
+++ b/include/linux/cmdline.h
@@ -31,7 +31,7 @@ static __always_inline size_t cmdline_strlcat(char *dest, const char *src, size_
}
/*
- * This function will append a builtin command line to the command
+ * This function will append or prepend a builtin command line to the command
* line provided by the bootloader. Kconfig options can be used to alter
* the behavior of this builtin command line.
* @dest: The destination of the final appended/prepended string.
@@ -50,6 +50,9 @@ static __always_inline void cmdline_build(char *dest, const char *src, size_t le
cmdline_strlcat(dest, CONFIG_CMDLINE, length);
return;
}
+
+ if (IS_ENABLED(CONFIG_CMDLINE_PREPEND) && sizeof(CONFIG_CMDLINE) > 1)
+ cmdline_strlcat(dest, CONFIG_CMDLINE " ", length);
#endif
if (dest != src)
cmdline_strlcat(dest, src, length);
--
2.25.0
^ permalink raw reply related
* [PATCH v2 1/7] cmdline: Add generic function to build command line.
From: Christophe Leroy @ 2021-03-02 17:25 UTC (permalink / raw)
To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman,
danielwa, robh, daniel
Cc: linux-arch, devicetree, linuxppc-dev, linux-kernel
In-Reply-To: <cover.1614705851.git.christophe.leroy@csgroup.eu>
This code provides architectures with a way to build command line
based on what is built in the kernel and what is handed over by the
bootloader, based on selected compile-time options.
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
include/linux/cmdline.h | 62 +++++++++++++++++++++++++++++++++++++++++
1 file changed, 62 insertions(+)
create mode 100644 include/linux/cmdline.h
diff --git a/include/linux/cmdline.h b/include/linux/cmdline.h
new file mode 100644
index 000000000000..ae3610bb0ee2
--- /dev/null
+++ b/include/linux/cmdline.h
@@ -0,0 +1,62 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _LINUX_CMDLINE_H
+#define _LINUX_CMDLINE_H
+
+static __always_inline size_t cmdline_strlen(const char *s)
+{
+ const char *sc;
+
+ for (sc = s; *sc != '\0'; ++sc)
+ ; /* nothing */
+ return sc - s;
+}
+
+static __always_inline size_t cmdline_strlcat(char *dest, const char *src, size_t count)
+{
+ size_t dsize = cmdline_strlen(dest);
+ size_t len = cmdline_strlen(src);
+ size_t res = dsize + len;
+
+ /* This would be a bug */
+ if (dsize >= count)
+ return count;
+
+ dest += dsize;
+ count -= dsize;
+ if (len >= count)
+ len = count - 1;
+ memcpy(dest, src, len);
+ dest[len] = 0;
+ return res;
+}
+
+/*
+ * This function will append a builtin command line to the command
+ * line provided by the bootloader. Kconfig options can be used to alter
+ * the behavior of this builtin command line.
+ * @dest: The destination of the final appended/prepended string.
+ * @src: The starting string or NULL if there isn't one. Must not equal dest.
+ * @length: the length of dest buffer.
+ */
+static __always_inline void cmdline_build(char *dest, const char *src, size_t length)
+{
+ if (length <= 0)
+ return;
+
+ dest[0] = 0;
+
+#ifdef CONFIG_CMDLINE
+ if (IS_ENABLED(CONFIG_CMDLINE_FORCE) || !src || !src[0]) {
+ cmdline_strlcat(dest, CONFIG_CMDLINE, length);
+ return;
+ }
+#endif
+ if (dest != src)
+ cmdline_strlcat(dest, src, length);
+#ifdef CONFIG_CMDLINE
+ if (IS_ENABLED(CONFIG_CMDLINE_EXTEND) && sizeof(CONFIG_CMDLINE) > 1)
+ cmdline_strlcat(dest, " " CONFIG_CMDLINE, length);
+#endif
+}
+
+#endif /* _LINUX_CMDLINE_H */
--
2.25.0
^ permalink raw reply related
* [PATCH v2 0/7] Improve boot command line handling
From: Christophe Leroy @ 2021-03-02 17:25 UTC (permalink / raw)
To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman,
danielwa, robh, daniel
Cc: linux-arch, devicetree, linuxppc-dev, linux-kernel
The purpose of this series is to improve and enhance the
handling of kernel boot arguments.
It is first focussed on powerpc but also extends the capability
for other arches.
This is based on suggestion from Daniel Walker <danielwa@cisco.com>
Christophe Leroy (7):
cmdline: Add generic function to build command line.
drivers: of: use cmdline building function
powerpc: convert to generic builtin command line
cmdline: Add capability to prepend the command line
powerpc: add capability to prepend default command line
cmdline: Gives architectures opportunity to use generically defined
boot cmdline manipulation
powerpc: use generic CMDLINE manipulations
arch/powerpc/Kconfig | 37 ++-----------------
arch/powerpc/kernel/prom_init.c | 35 +++---------------
drivers/of/fdt.c | 23 ++----------
include/linux/cmdline.h | 65 +++++++++++++++++++++++++++++++++
init/Kconfig | 56 ++++++++++++++++++++++++++++
5 files changed, 133 insertions(+), 83 deletions(-)
create mode 100644 include/linux/cmdline.h
--
2.25.0
^ permalink raw reply
* [PATCH v2 2/7] drivers: of: use cmdline building function
From: Christophe Leroy @ 2021-03-02 17:25 UTC (permalink / raw)
To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman,
danielwa, robh, daniel
Cc: linux-arch, devicetree, linuxppc-dev, linux-kernel
In-Reply-To: <cover.1614705851.git.christophe.leroy@csgroup.eu>
This patch uses the new cmdline building function to
concatenate the of provided cmdline with built-in parts
based on compile-time options.
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
drivers/of/fdt.c | 23 ++++-------------------
1 file changed, 4 insertions(+), 19 deletions(-)
diff --git a/drivers/of/fdt.c b/drivers/of/fdt.c
index dcc1dd96911a..cf2b95b8f298 100644
--- a/drivers/of/fdt.c
+++ b/drivers/of/fdt.c
@@ -25,6 +25,7 @@
#include <linux/serial_core.h>
#include <linux/sysfs.h>
#include <linux/random.h>
+#include <linux/cmdline.h>
#include <asm/setup.h> /* for COMMAND_LINE_SIZE */
#include <asm/page.h>
@@ -1050,26 +1051,10 @@ int __init early_init_dt_scan_chosen(unsigned long node, const char *uname,
/* Retrieve command line */
p = of_get_flat_dt_prop(node, "bootargs", &l);
- if (p != NULL && l > 0)
- strlcpy(data, p, min(l, COMMAND_LINE_SIZE));
+ if (l <= 0)
+ p = NULL;
- /*
- * CONFIG_CMDLINE is meant to be a default in case nothing else
- * managed to set the command line, unless CONFIG_CMDLINE_FORCE
- * is set in which case we override whatever was found earlier.
- */
-#ifdef CONFIG_CMDLINE
-#if defined(CONFIG_CMDLINE_EXTEND)
- strlcat(data, " ", COMMAND_LINE_SIZE);
- strlcat(data, CONFIG_CMDLINE, COMMAND_LINE_SIZE);
-#elif defined(CONFIG_CMDLINE_FORCE)
- strlcpy(data, CONFIG_CMDLINE, COMMAND_LINE_SIZE);
-#else
- /* No arguments from boot loader, use kernel's cmdl*/
- if (!((char *)data)[0])
- strlcpy(data, CONFIG_CMDLINE, COMMAND_LINE_SIZE);
-#endif
-#endif /* CONFIG_CMDLINE */
+ cmdline_build(data, p, COMMAND_LINE_SIZE);
pr_debug("Command line is: %s\n", (char *)data);
--
2.25.0
^ permalink raw reply related
* Re: [PATCH 0/2] Fix CMDLINE_EXTEND handling for FDT "bootargs"
From: Daniel Walker @ 2021-03-02 17:12 UTC (permalink / raw)
To: Rob Herring
Cc: Tyler Hicks, devicetree, Android Kernel Team, Catalin Marinas,
Arnd Bergmann, Frank Rowand, Marc Zyngier, linuxppc-dev,
linux-kernel@vger.kernel.org, Doug Anderson, Chris Packham,
Palmer Dabbelt, Greg Kroah-Hartman, Max Uvarov, Will Deacon,
Ard Biesheuvel, linux-arm-kernel
In-Reply-To: <CAL_JsqJ11D-7a3pwLTVd+rHjqDGBb=b8OU_a6h3Co-at+2qMtQ@mail.gmail.com>
On Mon, Mar 01, 2021 at 11:26:14AM -0600, Rob Herring wrote:
> +PPC folks and Daniel W
>
> On Mon, Mar 1, 2021 at 8:42 AM Will Deacon <will@kernel.org> wrote:
> >
> > On Mon, Mar 01, 2021 at 08:19:32AM -0600, Rob Herring wrote:
> > > On Thu, Feb 25, 2021 at 6:59 AM Will Deacon <will@kernel.org> wrote:
> > > > We recently [1] enabled support for CMDLINE_EXTEND on arm64, however
> > > > when I started looking at replacing Android's out-of-tree implementation [2]
> > >
> > > Did anyone go read the common, reworked version of all this I
> > > referenced that supports prepend and append. Here it is again[1].
> > > Maybe I should have been more assertive there and said 'extend' is
> > > ambiguous.
> >
> > I tried reading that, but (a) most of the series is not in the mailing list
> > archives and (b) the patch that _is_ doesn't touch CMDLINE_EXTEND at all.
> > Right now the code in mainline does the opposite of what it's documented to
> > do.
>
> Actually, there is a newer version I found:
>
> https://lore.kernel.org/linuxppc-dev/1551469472-53043-1-git-send-email-danielwa@cisco.com/
> https://lore.kernel.org/linuxppc-dev/1551469472-53043-2-git-send-email-danielwa@cisco.com/
> https://lore.kernel.org/linuxppc-dev/1551469472-53043-3-git-send-email-danielwa@cisco.com/
>
> (Once again, there's some weird threading going on)
>
I'm happy to work with anyone to resubmit the changes. We currently use the
changes in Cisco, and we have used them for many years.
I was planning to update and resubmit since someone has recently inquired about
why it wasn't upstream.
Daniel
^ permalink raw reply
* Re: [PATCH v19 00/13] Carry forward IMA measurement log on kexec on ARM64
From: Lakshmi Ramasubramanian @ 2021-03-02 15:25 UTC (permalink / raw)
To: Rob Herring
Cc: Mark Rutland, tao.li, Mimi Zohar, Paul Mackerras,
vincenzo.frascino, Frank Rowand, Sasha Levin, Stephen Rothwell,
Masahiro Yamada, James Morris, AKASHI, Takahiro, linux-arm-kernel,
Catalin Marinas, Serge E. Hallyn, devicetree, Pavel Tatashin,
Will Deacon, Prakhar Srivastava, Hsin-Yi Wang, Allison Randal,
Christophe Leroy, Matthias Brugger, balajib, dmitry.kasatkin,
linux-kernel@vger.kernel.org, James Morse, Greg Kroah-Hartman,
Joe Perches, linux-integrity, linuxppc-dev, Thiago Jung Bauermann
In-Reply-To: <CAL_JsqKiOVo2rDhstAA-jUkMJiajHM=uwfj3JQd64h_eEfSjTw@mail.gmail.com>
On 3/2/21 7:06 AM, Rob Herring wrote:
> On Sun, Feb 21, 2021 at 11:49 AM Lakshmi Ramasubramanian
> <nramas@linux.microsoft.com> wrote:
>>
>> On kexec file load Integrity Measurement Architecture (IMA) subsystem
>> may verify the IMA signature of the kernel and initramfs, and measure
>> it. The command line parameters passed to the kernel in the kexec call
>> may also be measured by IMA. A remote attestation service can verify
>> a TPM quote based on the TPM event log, the IMA measurement list, and
>> the TPM PCR data. This can be achieved only if the IMA measurement log
>> is carried over from the current kernel to the next kernel across
>> the kexec call.
>>
>> powerpc already supports carrying forward the IMA measurement log on
>> kexec. This patch set adds support for carrying forward the IMA
>> measurement log on kexec on ARM64.
>>
>> This patch set moves the platform independent code defined for powerpc
>> such that it can be reused for other platforms as well. A chosen node
>> "linux,ima-kexec-buffer" is added to the DTB for ARM64 to hold
>> the address and the size of the memory reserved to carry
>> the IMA measurement log.
>>
>> This patch set has been tested for ARM64 platform using QEMU.
>> I would like help from the community for testing this change on powerpc.
>> Thanks.
>>
>> This patch set is based on
>> commit f31e3386a4e9 ("ima: Free IMA measurement buffer after kexec syscall")
>> in https://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity.git
>> "ima-kexec-fixes" branch.
[...]
>>
>> Lakshmi Ramasubramanian (10):
>> kexec: Move ELF fields to struct kimage
>> arm64: Use ELF fields defined in 'struct kimage'
>> powerpc: Use ELF fields defined in 'struct kimage'
>> x86: Use ELF fields defined in 'struct kimage'
>> powerpc: Move ima buffer fields to struct kimage
>> powerpc: Enable passing IMA log to next kernel on kexec
>> powerpc: Move arch independent ima kexec functions to
>> drivers/of/kexec.c
>> kexec: Use fdt_appendprop_addrrange() to add ima buffer to FDT
>> powerpc: Delete unused function delete_fdt_mem_rsv()
>> arm64: Enable passing IMA log to next kernel on kexec
>>
>> Rob Herring (3):
>> of: Add a common kexec FDT setup function
>> arm64: Use common of_kexec_alloc_and_setup_fdt()
>> powerpc: Use common of_kexec_alloc_and_setup_fdt()
>>
>> arch/arm64/Kconfig | 1 +
>> arch/arm64/include/asm/kexec.h | 4 -
>> arch/arm64/kernel/machine_kexec_file.c | 194 +----------
>> arch/powerpc/Kconfig | 2 +-
>> arch/powerpc/include/asm/ima.h | 30 --
>> arch/powerpc/include/asm/kexec.h | 14 +-
>> arch/powerpc/kexec/Makefile | 7 -
>> arch/powerpc/kexec/elf_64.c | 30 +-
>> arch/powerpc/kexec/file_load.c | 183 +---------
>> arch/powerpc/kexec/file_load_64.c | 21 +-
>> arch/powerpc/kexec/ima.c | 219 ------------
>> arch/x86/include/asm/kexec.h | 5 -
>> arch/x86/kernel/crash.c | 14 +-
>> arch/x86/kernel/kexec-bzimage64.c | 2 +-
>> arch/x86/kernel/machine_kexec_64.c | 4 +-
>> drivers/of/Makefile | 6 +
>> drivers/of/kexec.c | 458 +++++++++++++++++++++++++
>> include/linux/kexec.h | 8 +
>> include/linux/of.h | 7 +
>> security/integrity/ima/ima.h | 4 -
>> security/integrity/ima/ima_kexec.c | 9 +-
>> 21 files changed, 539 insertions(+), 683 deletions(-)
>> delete mode 100644 arch/powerpc/include/asm/ima.h
>> delete mode 100644 arch/powerpc/kexec/ima.c
>> create mode 100644 drivers/of/kexec.c
>
> I fixed up the Fixes tags and applied for 5.13.
>
Thanks a lot Rob.
-lakshmi
^ permalink raw reply
* Re: [PATCH 0/2] Fix CMDLINE_EXTEND handling for FDT "bootargs"
From: Christophe Leroy @ 2021-03-02 15:16 UTC (permalink / raw)
To: Rob Herring
Cc: Tyler Hicks, devicetree, Marc Zyngier, Arnd Bergmann,
Greg Kroah-Hartman, Will Deacon, Frank Rowand, linuxppc-dev,
Doug Anderson, Chris Packham, Palmer Dabbelt, linux-arm-kernel,
Catalin Marinas, Max Uvarov, Android Kernel Team, Ard Biesheuvel,
linux-kernel@vger.kernel.org, Daniel Walker
In-Reply-To: <CAL_Jsq+Te5+kQzbAMCzuRCkmoZWBDKGhynUC8BfvOm=R5jT4Jg@mail.gmail.com>
Le 02/03/2021 à 15:56, Rob Herring a écrit :
> On Mon, Mar 1, 2021 at 11:45 AM Christophe Leroy
> <christophe.leroy@csgroup.eu> wrote:
>>
>>
>>
>> Le 01/03/2021 à 18:26, Rob Herring a écrit :
>>> +PPC folks and Daniel W
>>>
>>> On Mon, Mar 1, 2021 at 8:42 AM Will Deacon <will@kernel.org> wrote:
>>>>
>>>> On Mon, Mar 01, 2021 at 08:19:32AM -0600, Rob Herring wrote:
>>>>> On Thu, Feb 25, 2021 at 6:59 AM Will Deacon <will@kernel.org> wrote:
>>>>>> We recently [1] enabled support for CMDLINE_EXTEND on arm64, however
>>>>>> when I started looking at replacing Android's out-of-tree implementation [2]
>>>>>
>>>>> Did anyone go read the common, reworked version of all this I
>>>>> referenced that supports prepend and append. Here it is again[1].
>>>>> Maybe I should have been more assertive there and said 'extend' is
>>>>> ambiguous.
>>>>
>>>> I tried reading that, but (a) most of the series is not in the mailing list
>>>> archives and (b) the patch that _is_ doesn't touch CMDLINE_EXTEND at all.
>>>> Right now the code in mainline does the opposite of what it's documented to
>>>> do.
>>>
>>> Actually, there is a newer version I found:
>>>
>>> https://lore.kernel.org/linuxppc-dev/1551469472-53043-1-git-send-email-danielwa@cisco.com/
>>> https://lore.kernel.org/linuxppc-dev/1551469472-53043-2-git-send-email-danielwa@cisco.com/
>>> https://lore.kernel.org/linuxppc-dev/1551469472-53043-3-git-send-email-danielwa@cisco.com/
>>
>> This was seen as too much intrusive into powerpc.
>
> It looked like the main issue was string functions for KASAN?
This is one issue yes,
>
> As far as being too complex, I think that will be needed if you look
> at all architectures and non-DT cases.
As far as I remember, I could't understand why we absolutely need to define the command line string
in the common part of the code, leading to being obliged to use macros in order to allow the
architecture to specify in which section it wants the string.
Why not leave the definition of the string to the architecture and just declare it in the common
code, allowing the architecture to put it where it suits it and reducing opacity and allowing use of
standard static inline functions instead of uggly macros.
>
>> I proposed an alternative at
>> https://patchwork.ozlabs.org/project/linuxppc-dev/cover/cover.1554195798.git.christophe.leroy@c-s.fr/ but
>> never got any feedback.
>
> Didn't go to a list I subscribe to. In particular, if it had gone to
> DT list and into PW you would have gotten a reply from me.
>
Sorry for that. Original series from Daniel
(https://patchwork.ozlabs.org/project/linuxppc-dev/patch/20190319232448.45964-2-danielwa@cisco.com/)
was sent only to linuxppc-dev list, and Michael suggested to also send it to linux-arch list, and I
also always copy linux-kernel.
If there is new interest for that functionnality, I can try and rebase my series.
Christophe
^ permalink raw reply
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