Re: [RESEND][PATCH 7/8][SCSI]mpt3sas: Added Reply Descriptor Post Queue (RDPQ) Array support
From: Tomas Henzl
Date: Wed Aug 06 2014 - 11:57:20 EST
On 08/05/2014 06:41 PM, Sreekanth Reddy wrote:
> Hi Tomas,
>
> Can you please review this updated patch,
Hi Sreekanth,
the patch is mangled so a resend is needed anyway and I think you will
probably also want implement the changes you were asked for in the
mpt2sas sibling of this patch.
Thanks, Tomas
>
> Up to now, Driver allocates a single contiguous block of memory
> pool for all reply queues and passes down a single address in the
> ReplyDescriptorPostQueueAddress field of the IOC Init Request
> Message to the firmware.
>
> When firmware receives this address, it will program each of the
> Reply Descriptor Post Queue registers, as each reply queue has its
> own register. Thus the firmware, starting from a base address it
> determines the starting address of the subsequent reply queues
> through some simple arithmetic calculations.
>
> The size of this contiguous block of memory pool is directly proportional
> to number of MSI-X vectors and the HBA queue depth. For example higher
> MSIX vectors requires larger contiguous block of memory pool.
>
> But some of the OS kernels are unable to allocate this larger
> contiguous block of memory pool.
>
> So, the proposal is to allocate memory independently for each
> Reply Queue and pass down all of the addresses to the firmware.
> Then the firmware will just take each address and program the value
> into the correct register.
>
> When HBAs with older firmware(i.e. without RDPQ capability) is used
> with this new driver then the max_msix_vectors value would be set
> to 8 by default.
>
> Change set in v2:
>
> 1. Declared the following functions at the beginning of the mpt3sas_base.c
> file instead of moving all these functions before
> mpt3sas_base_map_resources() function
> a. _base_wait_for_doorbell_int()
> b. _base_wait_for_doorbell_ack()
> c. _base_wait_for_doorbell_not_used()
> d. _base_handshake_req_reply_wait()
> e. _base_get_ioc_facts()
>
> 2. Initially set the consistent DMA mask to 32 bit and then change it to 64
> bit mask after allocating RDPQ pools by calling the function
> _base_change_consistent_dma_mask. This is to ensure that all the upper 32
> bits of RDPQ entries's base address to be same.
>
> 3. Reduced the redundancy between the RDPQ and non-RDPQ support in these
> following functions
> a. _base_release_memory_pools()
> b. _base_allocate_memory_pools()
> c. _base_send_ioc_init()
> d. _base_make_ioc_operational()
>
> Signed-off-by: Sreekanth Reddy <Sreekanth.Reddy@xxxxxxxxxxxxx>
> ---
> drivers/scsi/mpt3sas/mpt3sas_base.c | 246
> ++++++++++++++++++++++++++++--------
> drivers/scsi/mpt3sas/mpt3sas_base.h | 18 ++-
> 2 files changed, 204 insertions(+), 60 deletions(-)
>
> diff --git a/drivers/scsi/mpt3sas/mpt3sas_base.c
> b/drivers/scsi/mpt3sas/mpt3sas_base.c
> index 153b2c1..20c2c7b 100644
> --- a/drivers/scsi/mpt3sas/mpt3sas_base.c
> +++ b/drivers/scsi/mpt3sas/mpt3sas_base.c
> @@ -92,6 +92,22 @@ MODULE_PARM_DESC(mpt3sas_fwfault_debug,
> " enable detection of firmware fault and halt firmware - (default=0)");
>
>
> +static int dma_mask;
> +
> +static int
> +_base_wait_for_doorbell_int(struct MPT3SAS_ADAPTER *ioc, int timeout,
> + int sleep_flag);
> +static int
> +_base_wait_for_doorbell_ack(struct MPT3SAS_ADAPTER *ioc, int timeout,
> + int sleep_flag);
> +static int
> +_base_wait_for_doorbell_not_used(struct MPT3SAS_ADAPTER *ioc, int timeout,
> + int sleep_flag);
> +static int
> +_base_handshake_req_reply_wait(struct MPT3SAS_ADAPTER *ioc, int
> request_bytes,
> + u32 *request, int reply_bytes, u16 *reply, int timeout, int
> sleep_flag);
> +static int
> +_base_get_ioc_facts(struct MPT3SAS_ADAPTER *ioc, int sleep_flag);
> /**
> * _scsih_set_fwfault_debug - global setting of ioc->fwfault_debug.
> *
> @@ -1482,17 +1498,23 @@ static int
> _base_config_dma_addressing(struct MPT3SAS_ADAPTER *ioc, struct pci_dev
> *pdev)
> {
> struct sysinfo s;
> - char *desc = NULL;
> + u64 consistent_dma_mask;
> +
> + if (dma_mask)
> + consistent_dma_mask = DMA_BIT_MASK(64);
> + else
> + consistent_dma_mask = DMA_BIT_MASK(32);
>
> if (sizeof(dma_addr_t) > 4) {
> const uint64_t required_mask =
> dma_get_required_mask(&pdev->dev);
> if ((required_mask > DMA_BIT_MASK(32)) &&
> !pci_set_dma_mask(pdev, DMA_BIT_MASK(64)) &&
> - !pci_set_consistent_dma_mask(pdev, DMA_BIT_MASK(64))) {
> + !pci_set_consistent_dma_mask(pdev,
> + DMA_BIT_MASK(consistent_dma_mask))) {
> ioc->base_add_sg_single = &_base_add_sg_single_64;
> ioc->sge_size = sizeof(Mpi2SGESimple64_t);
> - desc = "64";
> + dma_mask = 64;
> goto out;
> }
> }
> @@ -1501,19 +1523,30 @@ _base_config_dma_addressing(struct MPT3SAS_ADAPTER
> *ioc, struct pci_dev *pdev)
> && !pci_set_consistent_dma_mask(pdev, DMA_BIT_MASK(32))) {
> ioc->base_add_sg_single = &_base_add_sg_single_32;
> ioc->sge_size = sizeof(Mpi2SGESimple32_t);
> - desc = "32";
> + dma_mask = 32;
> } else
> return -ENODEV;
>
> out:
> si_meminfo(&s);
> pr_info(MPT3SAS_FMT
> - "%s BIT PCI BUS DMA ADDRESSING SUPPORTED, total mem (%ld kB)\n",
> - ioc->name, desc, convert_to_kb(s.totalram));
> + "%d BIT PCI BUS DMA ADDRESSING SUPPORTED, total mem (%ld kB)\n",
> + ioc->name, dma_mask, convert_to_kb(s.totalram));
>
> return 0;
> }
>
> +static int
> +_base_change_consistent_dma_mask(struct MPT3SAS_ADAPTER *ioc,
> + struct pci_dev *pdev)
> +{
> + if (pci_set_consistent_dma_mask(pdev, DMA_BIT_MASK(64))) {
> + if (pci_set_consistent_dma_mask(pdev, DMA_BIT_MASK(32)))
> + return -ENODEV;
> + }
> + return 0;
> +}
> +
> /**
> * _base_check_enable_msix - checks MSIX capabable.
> * @ioc: per adapter object
> @@ -1729,6 +1762,9 @@ _base_enable_msix(struct MPT3SAS_ADAPTER *ioc)
> ": %d, max_msix_vectors: %d\n", ioc->name, ioc->msix_vector_count,
> ioc->cpu_count, max_msix_vectors);
>
> + if (!ioc->rdpq_array_enable && max_msix_vectors == -1)
> + max_msix_vectors = 8;
> +
> if (max_msix_vectors > 0) {
> ioc->reply_queue_count = min_t(int, max_msix_vectors,
> ioc->reply_queue_count);
> @@ -1852,6 +1888,16 @@ mpt3sas_base_map_resources(struct MPT3SAS_ADAPTER
> *ioc)
> }
>
> _base_mask_interrupts(ioc);
> +
> + r = _base_get_ioc_facts(ioc, CAN_SLEEP);
> + if (r)
> + goto out_fail;
> +
> + if (!ioc->rdpq_array_enable_assigned) {
> + ioc->rdpq_array_enable = ioc->rdpq_array_capable;
> + ioc->rdpq_array_enable_assigned = 1;
> + }
> +
> r = _base_enable_msix(ioc);
> if (r)
> goto out_fail;
> @@ -2527,7 +2573,8 @@ _base_static_config_pages(struct MPT3SAS_ADAPTER *ioc)
> static void
> _base_release_memory_pools(struct MPT3SAS_ADAPTER *ioc)
> {
> - int i;
> + int i = 0;
> + struct reply_post_struct *rps;
>
> dexitprintk(ioc, pr_info(MPT3SAS_FMT "%s\n", ioc->name,
> __func__));
> @@ -2572,15 +2619,25 @@ _base_release_memory_pools(struct MPT3SAS_ADAPTER
> *ioc)
> ioc->reply_free = NULL;
> }
>
> - if (ioc->reply_post_free) {
> - pci_pool_free(ioc->reply_post_free_dma_pool,
> - ioc->reply_post_free, ioc->reply_post_free_dma);
> + if (ioc->reply_post) {
> + do {
> + rps = &ioc->reply_post[i];
> + if (rps->reply_post_free) {
> + pci_pool_free(
> + ioc->reply_post_free_dma_pool,
> + rps->reply_post_free,
> + rps->reply_post_free_dma);
> + dexitprintk(ioc, pr_info(MPT3SAS_FMT
> + "reply_post_free_pool(0x%p): free\n",
> + ioc->name, rps->reply_post_free));
> + rps->reply_post_free = NULL;
> + }
> + } while (ioc->rdpq_array_enable &&
> + (++i < ioc->reply_queue_count));
> +
> if (ioc->reply_post_free_dma_pool)
> pci_pool_destroy(ioc->reply_post_free_dma_pool);
> - dexitprintk(ioc, pr_info(MPT3SAS_FMT
> - "reply_post_free_pool(0x%p): free\n", ioc->name,
> - ioc->reply_post_free));
> - ioc->reply_post_free = NULL;
> + kfree(ioc->reply_post);
> }
>
> if (ioc->config_page) {
> @@ -2727,6 +2784,69 @@ _base_allocate_memory_pools(struct MPT3SAS_ADAPTER
> *ioc, int sleep_flag)
> ioc->max_sges_in_chain_message, ioc->shost->sg_tablesize,
> ioc->chains_needed_per_io));
>
> + /* reply post queue, 16 byte align */
> + reply_post_free_sz = ioc->reply_post_queue_depth *
> + sizeof(Mpi2DefaultReplyDescriptor_t);
> + if (ioc->rdpq_array_enable)
> + sz = reply_post_free_sz;
> + else {
> + if (_base_is_controller_msix_enabled(ioc))
> + sz = reply_post_free_sz * ioc->reply_queue_count;
> + else
> + sz = reply_post_free_sz;
> + }
> +
> + ioc->reply_post = kcalloc((ioc->rdpq_array_enable) ?
> + (ioc->reply_queue_count):1,
> + sizeof(struct reply_post_struct), GFP_KERNEL);
> +
> + if (!ioc->reply_post) {
> + pr_err(MPT3SAS_FMT "reply_post_free pool: kcalloc failed\n",
> + ioc->name);
> + goto out;
> + }
> + ioc->reply_post_free_dma_pool = pci_pool_create("reply_post_free pool",
> + ioc->pdev, sz, 16, 0);
> + if (!ioc->reply_post_free_dma_pool) {
> + pr_err(MPT3SAS_FMT
> + "reply_post_free pool: pci_pool_create failed\n",
> + ioc->name);
> + goto out;
> + }
> + i = 0;
> + do {
> + ioc->reply_post[i].reply_post_free =
> + pci_pool_alloc(ioc->reply_post_free_dma_pool,
> + GFP_KERNEL,
> + &ioc->reply_post[i].reply_post_free_dma);
> + if (!ioc->reply_post[i].reply_post_free) {
> + pr_err(MPT3SAS_FMT
> + "reply_post_free pool: pci_pool_alloc failed\n",
> + ioc->name);
> + goto out;
> + }
> + memset(ioc->reply_post[i].reply_post_free, 0, sz);
> + dinitprintk(ioc, pr_info(MPT3SAS_FMT
> + "reply post free pool (0x%p): depth(%d),"
> + "element_size(%d), pool_size(%d kB)\n", ioc->name,
> + ioc->reply_post[i].reply_post_free,
> + ioc->reply_post_queue_depth, 8, sz/1024));
> + dinitprintk(ioc, pr_info(MPT3SAS_FMT
> + "reply_post_free_dma = (0x%llx)\n", ioc->name,
> + (unsigned long long)
> + ioc->reply_post[i].reply_post_free_dma));
> + total_sz += sz;
> + } while (ioc->rdpq_array_enable && (++i < ioc->reply_queue_count));
> +
> + if (dma_mask == 64) {
> + if (_base_change_consistent_dma_mask(ioc, ioc->pdev) != 0) {
> + pr_warn(MPT3SAS_FMT
> + "no suitable consistent DMA mask for %s\n",
> + ioc->name, pci_name(ioc->pdev));
> + goto out;
> + }
> + }
> +
> ioc->scsiio_depth = ioc->hba_queue_depth -
> ioc->hi_priority_depth - ioc->internal_depth;
>
> @@ -2941,40 +3061,6 @@ _base_allocate_memory_pools(struct MPT3SAS_ADAPTER
> *ioc, int sleep_flag)
> ioc->name, (unsigned long long)ioc->reply_free_dma));
> total_sz += sz;
>
> - /* reply post queue, 16 byte align */
> - reply_post_free_sz = ioc->reply_post_queue_depth *
> - sizeof(Mpi2DefaultReplyDescriptor_t);
> - if (_base_is_controller_msix_enabled(ioc))
> - sz = reply_post_free_sz * ioc->reply_queue_count;
> - else
> - sz = reply_post_free_sz;
> - ioc->reply_post_free_dma_pool = pci_pool_create("reply_post_free pool",
> - ioc->pdev, sz, 16, 0);
> - if (!ioc->reply_post_free_dma_pool) {
> - pr_err(MPT3SAS_FMT
> - "reply_post_free pool: pci_pool_create failed\n",
> - ioc->name);
> - goto out;
> - }
> - ioc->reply_post_free = pci_pool_alloc(ioc->reply_post_free_dma_pool ,
> - GFP_KERNEL, &ioc->reply_post_free_dma);
> - if (!ioc->reply_post_free) {
> - pr_err(MPT3SAS_FMT
> - "reply_post_free pool: pci_pool_alloc failed\n",
> - ioc->name);
> - goto out;
> - }
> - memset(ioc->reply_post_free, 0, sz);
> - dinitprintk(ioc, pr_info(MPT3SAS_FMT "reply post free pool" \
> - "(0x%p): depth(%d), element_size(%d), pool_size(%d kB)\n",
> - ioc->name, ioc->reply_post_free, ioc->reply_post_queue_depth, 8,
> - sz/1024));
> - dinitprintk(ioc, pr_info(MPT3SAS_FMT
> - "reply_post_free_dma = (0x%llx)\n",
> - ioc->name, (unsigned long long)
> - ioc->reply_post_free_dma));
> - total_sz += sz;
> -
> ioc->config_page_sz = 512;
> ioc->config_page = pci_alloc_consistent(ioc->pdev,
> ioc->config_page_sz, &ioc->config_page_dma);
> @@ -3657,6 +3743,9 @@ _base_get_ioc_facts(struct MPT3SAS_ADAPTER *ioc, int
> sleep_flag)
> facts->IOCCapabilities = le32_to_cpu(mpi_reply.IOCCapabilities);
> if ((facts->IOCCapabilities &
> MPI2_IOCFACTS_CAPABILITY_INTEGRATED_RAID))
> ioc->ir_firmware = 1;
> + if ((facts->IOCCapabilities &
> + MPI2_IOCFACTS_CAPABILITY_RDPQ_ARRAY_CAPABLE))
> + ioc->rdpq_array_capable = 1;
> facts->FWVersion.Word = le32_to_cpu(mpi_reply.FWVersion.Word);
> facts->IOCRequestFrameSize =
> le16_to_cpu(mpi_reply.IOCRequestFrameSize);
> @@ -3693,9 +3782,12 @@ _base_send_ioc_init(struct MPT3SAS_ADAPTER *ioc, int
> sleep_flag)
> {
> Mpi2IOCInitRequest_t mpi_request;
> Mpi2IOCInitReply_t mpi_reply;
> - int r;
> + int i, r = 0;
> struct timeval current_time;
> u16 ioc_status;
> + u32 reply_post_free_array_sz = 0;
> + Mpi2IOCInitRDPQArrayEntry *reply_post_free_array = NULL;
> + dma_addr_t reply_post_free_array_dma;
>
> dinitprintk(ioc, pr_info(MPT3SAS_FMT "%s\n", ioc->name,
> __func__));
> @@ -3724,9 +3816,31 @@ _base_send_ioc_init(struct MPT3SAS_ADAPTER *ioc, int
> sleep_flag)
> cpu_to_le64((u64)ioc->request_dma);
> mpi_request.ReplyFreeQueueAddress =
> cpu_to_le64((u64)ioc->reply_free_dma);
> - mpi_request.ReplyDescriptorPostQueueAddress =
> - cpu_to_le64((u64)ioc->reply_post_free_dma);
>
> + if (ioc->rdpq_array_enable) {
> + reply_post_free_array_sz = ioc->reply_queue_count *
> + sizeof(Mpi2IOCInitRDPQArrayEntry);
> + reply_post_free_array = pci_alloc_consistent(ioc->pdev,
> + reply_post_free_array_sz, &reply_post_free_array_dma);
> + if (!reply_post_free_array) {
> + pr_err(MPT3SAS_FMT
> + "reply_post_free_array: pci_alloc_consistent failed\n",
> + ioc->name);
> + r = -ENOMEM;
> + goto out;
> + }
> + memset(reply_post_free_array, 0, reply_post_free_array_sz);
> + for (i = 0; i < ioc->reply_queue_count; i++)
> + reply_post_free_array[i].RDPQBaseAddress =
> + cpu_to_le64(
> + (u64)ioc->reply_post[i].reply_post_free_dma);
> + mpi_request.MsgFlags = MPI2_IOCINIT_MSGFLAG_RDPQ_ARRAY_MODE;
> + mpi_request.ReplyDescriptorPostQueueAddress =
> + cpu_to_le64((u64)reply_post_free_array_dma);
> + } else {
> + mpi_request.ReplyDescriptorPostQueueAddress =
> + cpu_to_le64((u64)ioc->reply_post[0].reply_post_free_dma);
> + }
>
> /* This time stamp specifies number of milliseconds
> * since epoch ~ midnight January 1, 1970.
> @@ -3754,7 +3868,7 @@ _base_send_ioc_init(struct MPT3SAS_ADAPTER *ioc, int
> sleep_flag)
> if (r != 0) {
> pr_err(MPT3SAS_FMT "%s: handshake failed (r=%d)\n",
> ioc->name, __func__, r);
> - return r;
> + goto out;
> }
>
> ioc_status = le16_to_cpu(mpi_reply.IOCStatus) & MPI2_IOCSTATUS_MASK;
> @@ -3764,7 +3878,12 @@ _base_send_ioc_init(struct MPT3SAS_ADAPTER *ioc, int
> sleep_flag)
> r = -EIO;
> }
>
> - return 0;
> +out:
> + if (reply_post_free_array)
> + pci_free_consistent(ioc->pdev, reply_post_free_array_sz,
> + reply_post_free_array,
> + reply_post_free_array_dma);
> + return r;
> }
>
> /**
> @@ -4314,7 +4433,7 @@ _base_make_ioc_operational(struct MPT3SAS_ADAPTER
> *ioc, int sleep_flag)
> struct _tr_list *delayed_tr, *delayed_tr_next;
> struct adapter_reply_queue *reply_q;
> long reply_post_free;
> - u32 reply_post_free_sz;
> + u32 reply_post_free_sz, index = 0;
>
> dinitprintk(ioc, pr_info(MPT3SAS_FMT "%s\n", ioc->name,
> __func__));
> @@ -4385,9 +4504,9 @@ _base_make_ioc_operational(struct MPT3SAS_ADAPTER
> *ioc, int sleep_flag)
> _base_assign_reply_queues(ioc);
>
> /* initialize Reply Post Free Queue */
> - reply_post_free = (long)ioc->reply_post_free;
> reply_post_free_sz = ioc->reply_post_queue_depth *
> sizeof(Mpi2DefaultReplyDescriptor_t);
> + reply_post_free = (long)ioc->reply_post[index].reply_post_free;
> list_for_each_entry(reply_q, &ioc->reply_queue_list, list) {
> reply_q->reply_post_host_index = 0;
> reply_q->reply_post_free = (Mpi2ReplyDescriptorsUnion_t *)
> @@ -4397,7 +4516,15 @@ _base_make_ioc_operational(struct MPT3SAS_ADAPTER
> *ioc, int sleep_flag)
> cpu_to_le64(ULLONG_MAX);
> if (!_base_is_controller_msix_enabled(ioc))
> goto skip_init_reply_post_free_queue;
> - reply_post_free += reply_post_free_sz;
> + /*
> + * If RDPQ is enabled, switch to the next allocation.
> + * Otherwise advance within the contiguous region.
> + */
> + if (ioc->rdpq_array_enable)
> + reply_post_free = (long)
> + ioc->reply_post[++index].reply_post_free;
> + else
> + reply_post_free += reply_post_free_sz;
> }
> skip_init_reply_post_free_queue:
>
> @@ -4508,6 +4635,7 @@ mpt3sas_base_attach(struct MPT3SAS_ADAPTER *ioc)
> goto out_free_resources;
> }
>
> + ioc->rdpq_array_enable_assigned = 0;
> r = mpt3sas_base_map_resources(ioc);
> if (r)
> goto out_free_resources;
> @@ -4884,6 +5012,12 @@ mpt3sas_base_hard_reset_handler(struct
> MPT3SAS_ADAPTER *ioc, int sleep_flag,
> r = _base_get_ioc_facts(ioc, CAN_SLEEP);
> if (r)
> goto out;
> +
> + if (ioc->rdpq_array_enable && !ioc->rdpq_array_capable)
> + panic("%s: Issue occurred with flashing controller firmware."
> + "Please reboot the system and ensure that the correct"
> + "firmware version is running\n", ioc->name);
> +
> r = _base_make_ioc_operational(ioc, sleep_flag);
> if (!r)
> _base_reset_handler(ioc, MPT3_IOC_DONE_RESET);
> diff --git a/drivers/scsi/mpt3sas/mpt3sas_base.h
> b/drivers/scsi/mpt3sas/mpt3sas_base.h
> index ae97f46..fd5d505 100644
> --- a/drivers/scsi/mpt3sas/mpt3sas_base.h
> +++ b/drivers/scsi/mpt3sas/mpt3sas_base.h
> @@ -569,6 +569,11 @@ struct mpt3sas_port_facts {
> u16 MaxPostedCmdBuffers;
> };
>
> +struct reply_post_struct {
> + Mpi2ReplyDescriptorsUnion_t *reply_post_free;
> + dma_addr_t reply_post_free_dma;
> +};
> +
> /**
> * enum mutex_type - task management mutex type
> * @TM_MUTEX_OFF: mutex is not required becuase calling function is
> acquiring it
> @@ -712,8 +717,11 @@ typedef void (*MPT3SAS_FLUSH_RUNNING_CMDS)(struct
> MPT3SAS_ADAPTER *ioc);
> * @reply_free_dma_pool:
> * @reply_free_host_index: tail index in pool to insert free replys
> * @reply_post_queue_depth: reply post queue depth
> - * @reply_post_free: pool for reply post (64bit descriptor)
> - * @reply_post_free_dma:
> + * @reply_post_struct: struct for reply_post_free physical & virt address
> + * @rdpq_array_capable: FW supports multiple reply queue addresses in
> ioc_init
> + * @rdpq_array_enable: rdpq_array support is enabled in the driver
> + * @rdpq_array_enable_assigned: this ensures that rdpq_array_enable flag
> + * is assigned only ones
> * @reply_queue_count: number of reply queue's
> * @reply_queue_list: link list contaning the reply queue info
> * @reply_post_host_index: head index in the pool where FW completes IO
> @@ -914,8 +922,10 @@ struct MPT3SAS_ADAPTER {
>
> /* reply post queue */
> u16 reply_post_queue_depth;
> - Mpi2ReplyDescriptorsUnion_t *reply_post_free;
> - dma_addr_t reply_post_free_dma;
> + struct reply_post_struct *reply_post;
> + u8 rdpq_array_capable;
> + u8 rdpq_array_enable;
> + u8 rdpq_array_enable_assigned;
> struct dma_pool *reply_post_free_dma_pool;
> u8 reply_queue_count;
> struct list_head reply_queue_list;
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