From bf7325882525b580c4e41cd36845bcf8113307fe Mon Sep 17 00:00:00 2001 From: Christophe JAILLET Date: Sun, 7 Nov 2021 09:32:58 +0100 Subject: [PATCH] PCI: brcmstb: Declare 'used' as bitmap, not unsigned long The 'used' field of 'struct brcm_msi' is used as a bitmap. Declare it with DECLARE_BITMAP() and adjust users accordingly. This fixes a harmless Coverity warning about array vs singleton usage. This bitmap can be used for either legacy or MSI interrupts, which require a size of BRCM_INT_PCI_MSI_LEGACY_NR or BRCM_INT_PCI_MSI_NR respectively. Add a BUILD_BUG_ON() to ensure it is large enough. Suggested-by: Krzysztof Wilczynski Addresses-Coverity: "Out-of-bounds access (ARRAY_VS_SINGLETON)" Link: https://lore.kernel.org/r/e6d9da2112aab2939d1507b90962d07bfd735b4c.1636273671.git.christophe.jaillet@wanadoo.fr Signed-off-by: Christophe JAILLET Signed-off-by: Lorenzo Pieralisi Signed-off-by: Bjorn Helgaas Reviewed-by: Florian Fainelli --- drivers/pci/controller/pcie-brcmstb.c | 13 +++++++++---- 1 file changed, 9 insertions(+), 4 deletions(-) diff --git a/drivers/pci/controller/pcie-brcmstb.c b/drivers/pci/controller/pcie-brcmstb.c index 1fc7bd49a7ad3..b016e43628bb3 100644 --- a/drivers/pci/controller/pcie-brcmstb.c +++ b/drivers/pci/controller/pcie-brcmstb.c @@ -266,8 +266,7 @@ struct brcm_msi { struct mutex lock; /* guards the alloc/free operations */ u64 target_addr; int irq; - /* used indicates which MSI interrupts have been alloc'd */ - unsigned long used; + DECLARE_BITMAP(used, BRCM_INT_PCI_MSI_NR); bool legacy; /* Some chips have MSIs in bits [31..24] of a shared register. */ int legacy_shift; @@ -534,7 +533,7 @@ static int brcm_msi_alloc(struct brcm_msi *msi) int hwirq; mutex_lock(&msi->lock); - hwirq = bitmap_find_free_region(&msi->used, msi->nr, 0); + hwirq = bitmap_find_free_region(msi->used, msi->nr, 0); mutex_unlock(&msi->lock); return hwirq; @@ -543,7 +542,7 @@ static int brcm_msi_alloc(struct brcm_msi *msi) static void brcm_msi_free(struct brcm_msi *msi, unsigned long hwirq) { mutex_lock(&msi->lock); - bitmap_release_region(&msi->used, hwirq, 0); + bitmap_release_region(msi->used, hwirq, 0); mutex_unlock(&msi->lock); } @@ -661,6 +660,12 @@ static int brcm_pcie_enable_msi(struct brcm_pcie *pcie) msi->irq = irq; msi->legacy = pcie->hw_rev < BRCM_PCIE_HW_REV_33; + /* + * Sanity check to make sure that the 'used' bitmap in struct brcm_msi + * is large enough. + */ + BUILD_BUG_ON(BRCM_INT_PCI_MSI_LEGACY_NR > BRCM_INT_PCI_MSI_NR); + if (msi->legacy) { msi->intr_base = msi->base + PCIE_INTR2_CPU_BASE; msi->nr = BRCM_INT_PCI_MSI_LEGACY_NR; -- 2.49.0