Thank you for your contribution! Sashiko AI review found 3 potential issue(s) to consider:
New issues: - [High] Using a hardware-derived `bus_type` field to conditionally unmap devm-managed resources leads to double-frees and double-unmaps on PCI devices. - [High] Incorrect error check for `pcim_request_region` causes `atyfb_pci_probe` to always fail with `-EBUSY`. Pre-existing issues: - [High] `iounmap` is called on a memory pointer that was offset from its base allocation address for non-PCI (Atari) devices. -- --- Patch [5]: [PATCH 5/5] fbdev: atyfb: Convert to managed PCI and ioremap API --- commit 9c27a62b3d8989d1641e7061c71fbeeb223ac2ec Author: Shixiong Ou <[email protected]> fbdev: atyfb: Convert to managed PCI and ioremap API This commit converts the atyfb driver's PCI initialization path to use devres-managed APIs like pcim_request_region() and devm_ioremap(). It also restricts manual cleanup during driver removal to non-PCI devices only. > diff --git a/drivers/video/fbdev/aty/atyfb_base.c > b/drivers/video/fbdev/aty/atyfb_base.c > index 9fc5af09f86c4..97cc8b6a93614 100644 > --- a/drivers/video/fbdev/aty/atyfb_base.c > +++ b/drivers/video/fbdev/aty/atyfb_base.c [ ... ] > @@ -3552,7 +3549,7 @@ static int atyfb_pci_probe(struct pci_dev *pdev, > /* Reserve space */ > res_start = rp->start; > res_size = resource_size(rp); > - if (!request_mem_region(res_start, res_size, "atyfb")) > + if (!pcim_request_region(pdev, rp - pdev->resource, "atyfb")) > return -EBUSY; [Severity: High] Since pcim_request_region() returns 0 on success and a negative error code on failure, will this condition cause the probe to fail unconditionally with -EBUSY when the region is successfully requested? [ ... ] > @@ -3733,10 +3722,13 @@ static void atyfb_remove(struct fb_info *info) > arch_phys_wc_del(par->wc_cookie); > > #ifndef __sparc__ > - if (par->ati_regbase) > - iounmap(par->ati_regbase); > - if (info->screen_base) > - iounmap(info->screen_base); > + /* For PCI devices, devm handles unmapping automatically */ > + if (par->bus_type != PCI) { > + if (par->ati_regbase) > + iounmap(par->ati_regbase); [Severity: High] Does par->bus_type reliably identify PCI devices at this point? During device initialization in aty_init(), par->bus_type is overwritten with a value read from a hardware register: par->bus_type = (stat0 >> 0) & 0x07; If a PCI device reports a non-PCI bus type (like ISA) from the hardware register, could this cause par->bus_type != PCI to evaluate to true, resulting in a double-unmap of the devm-managed ati_regbase here, as well as a double-free of the memory region later in this function? [Severity: High] This is a pre-existing issue, but for non-PCI devices (like Atari), par->ati_regbase can be initialized with an offset: par->ati_regbase = ioremap(phys_guiregbase[m64_num], 0x10000) + 0xFC00ul; Since par->ati_regbase is an offset pointer in those cases, will passing it directly to iounmap() here cause a kernel panic? > + if (info->screen_base) > + iounmap(info->screen_base); > + } -- Sashiko AI review ยท https://sashiko.dev/#/patchset/[email protected]?part=5
