Re: How does PCIe appear to the host?

>> Here's what ACPI has to say. As I mentioned, dmesg is identical >> with or without the card. > There are devices out there that require a relatively recent host ( > '3rd generation PCIE' or somesuch ). I am inclined to doubt that's what's up here. The Q1900M fails; the one that works is an As

Re: How does PCIe appear to the host?

Hello, On Thu, 3 Oct 2024 11:27:26 -0400 (EDT) Mouse wrote: > Here's what ACPI has to say. As I mentioned, dmesg is identical with > or without the card. There are devices out there that require a relatively recent host ( '3rd generation PCIE' or somesuch ). I've seen this on a PCIe powermac -

Re: How does PCIe appear to the host?

>> It's supposed to negotiate down to x1? > Yes. Okay. I've dropped the manufacturer an email asking whether this device is supposed to work in a mechanically x16 slot which has only one lane available to it. The primary chip on the board is indeed marked with the JMicron logo and "JMB585" (it's

Re: How does PCIe appear to the host?

mo...@rodents-montreal.org (Mouse) writes: >It's supposed to negotiate down to x1? Yes. > Then either Vantec or ASRock >has done something odd or my particular Q1900M has a duff "x16" slot, >because it doesn't work. I once had a PCIe network card in a x16 slot that didn't work reliable and wasn

Re: How does PCIe appear to the host?

>> ahcisata0 at pci2 dev 0 function 0: vendor 0x197b product 0x0585 > That's a JMicron JMB585 which has a PCIe Gen3 x2 interface and > provides five 6Gbps SATA ports. That sounds right; the card has five SATA connectors and its ppb reports "link is x2 @ 5.0GT/s". > If your board has eight SATA po

Re: How does PCIe appear to the host?

>>> [...] a 5-port PCIe SATA card [...] >> In case it matters to anyone, the card is identified, on the box and >> on a sticker on the card itself, as a UGT-ST655, and it comes from >> Vantec. As one of my messages quoted autoconf as saying, it shows >> up as vendor 0x197b product 0x0585. > [T]he

Re: How does PCIe appear to the host?

mo...@rodents-montreal.org (Mouse) writes: >ahcisata0 at pci2 dev 0 function 0: vendor 0x197b product 0x0585 That's a JMicron JMB585 which has a PCIe Gen3 x2 interface and provides five 6Gbps SATA ports. If your board has eight SATA ports, then one of the SATA ports probably has an additional 1-t

Re: How does PCIe appear to the host?

This used to be my day job, but I'm only good at doing this on Linux. Looking at the ids on the pciids database, you have a JMB58x AHCI SATA controller. I'm not sure if that helps or not, but the next step for me would be to dive into output of lspci and what the registers there say. And I think

Re: How does PCIe appear to the host?

> [...]. I just today picked up a 5-port PCIe SATA card and tried it. In case it matters to anyone, the card is identified, on the box and on a sticker on the card itself, as a UGT-ST655, and it comes from Vantec. As one of my messages quoted autoconf as saying, it shows up as vendor 0x197b produ

Re: How does PCIe appear to the host?

>> If you're plugging in a card and it isn't seen, I'd check the BIOS >> and look for any pcie settings it might have. > I suspect it's worse than that in this case; see mlelstv's mail, > explaining that there are only four lanes available total, so my > "x16" slot is [actually x1 electrically] I

Re: How does PCIe appear to the host?

Date:Thu, 3 Oct 2024 01:13:52 -0400 (EDT) From:Mouse Message-ID: <202410030513.baa08...@stone.rodents-montreal.org> | One of these machines is an ASRock Q1900M. It has only two SATA ports | onboard; it has two PCIe x1 slots and a PCIe x16 slot. I just today |

Re: How does PCIe appear to the host?

First, my thanks to everyone; while the news is not great from the perspective of getting things working, it has greatly improved my understanding of PCIe, so in that sense it was a success. You people are a marvelous resource! > It's been my experience that pcie busses show up as pci busses from

Re: How does PCIe appear to the host?

hello. It's been my experience that pcie busses show up as pci busses from the software perspective and, as you note, simply have more capabilities than standard pci connections. If you're plugging in a card and it isn't seen, I'd check the BIOS and look for any pcie settings it might

Re: struct vnode::v_mount access rules

> Date: Thu, 3 Oct 2024 10:13:17 +0200 > From: "J. Hannken-Illjes" > > > On 1. Oct 2024, at 18:57, Taylor R Campbell > > wrote: > > > > I think the answer is no, nothing here precludes a concurrent > > vcache_reclaim from writing to fp->f_vnode->v_mount at the same time > > do_sys_fstatvfs is

Re: How does PCIe appear to the host?

mo...@rodents-montreal.org (Mouse) writes: >I note a possible conflict between the "x1" and the presence of a x16 >slot; that 1 is coming from the PCIE_LCAP_MAX_WIDTH bits in PCIE_LCAP, >which makes me wonder whether something needs configuring to run the >x16 slot at more than x1. The card does

Re: struct vnode::v_mount access rules

> On 1. Oct 2024, at 18:57, Taylor R Campbell > wrote: > > Under what circumstances is access to struct vnode::v_mount allowed? > > A vnode may be concurrently revoked at any time. Part of revoking a > vnode vp, in vcache_reclaim, involves vfs_insmntque to set vp->v_mount > to dead_rootmount.