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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?9pm/QPelYhVd+5C5G17htaAp1mj7iO2cB67sn250LWijmgK4ao6nRT6nxcyU?= =?us-ascii?Q?x+iXT0Ab7K106aGNfChtarWy/OJXPRrtjsPGJNu0ixBeHg/3QhXqOpGAoohy?= =?us-ascii?Q?DRXLn4pubuE/WfbrEK9mNOEmNI3GagbTmqo6CM9QhTPIV2jmDm7+CGLeSgkG?= =?us-ascii?Q?ifAyPhLVYziR8SiK1ROT+oLwXHtEsmtaTdFeebBfB9eR9i/ipPJyOERRE6D8?= =?us-ascii?Q?8bkG0CC7lNYBJEkfA7EuXz9s4uCG67Gjx7FV2bVZ7XoY+GuCs0AefVPAvKVp?= =?us-ascii?Q?XtQhXB5Nr70aB2DLARPHOIWoQObHj7OiaA0wls393u4RHG54u+4v0/B447Ds?= =?us-ascii?Q?P7dXydj3kqKupEWDnJyZFbW4V4DdpfhGNxCiMdRZdofoME+/BH2o3Ef6ud8V?= =?us-ascii?Q?gHz1qTcsPWUJDf3TElcnqk2v0XBimMu344tR2JUCmdu7r9Zb+x4bl3q+xlZf?= =?us-ascii?Q?q9eWXlpjrxmpH3mlX1N/KVbG3vn3TgfxtQTF/zKhYHFednCZaYKIrSv4wQ1c?= =?us-ascii?Q?gj1FtdJoFtB3gaMRg503yaxvFH4/yVhJe/UMZQ6SUvmlb/LGtU758whvk67q?= =?us-ascii?Q?ojjCCQ/es43E2WM4RnYL2U+lAr9cQEeSxNH7YGG1AjC3g34dgQn1li1JofwJ?= =?us-ascii?Q?sEDNYk4j6HY6b351d1eri4ZarekEPv1arqcoOpsDf+Nww/H4TNsXr+D2CnA1?= =?us-ascii?Q?YXoV9rXgsPPVrGZLdxdq4jJNwsT57MQVgS0XcyBtyRq563GvBMGa67eWTcB6?= =?us-ascii?Q?U5Fv3lBfVOYeeG7aU+d0shA0bkC70ewktpSZT21f4kSHyypIi5x7S+IQQQk8?= =?us-ascii?Q?nEdUKHoGnyLdBVksUeB25I6lY5huiZ3OauCSWVw8Xr2dGbD6PE7ja0TJq3AQ?= =?us-ascii?Q?fwfP5SdLeQeNTF2kRydf+jZadFukatqJGfiafGgy4cYavrp10nIz51wKjpCN?= =?us-ascii?Q?cL6+/OvJXsnsBaB+JyvhvTDMN7BZeVLMPrlUXOtQLws8S59YKXI0utjLkGLK?= =?us-ascii?Q?IeKb3dL7wU1E6JiKDAonogoTxpknHk8h0aAr4XiEfUKqjrVRXB1vx/v4jBVp?= =?us-ascii?Q?qBcvbSkoNMtDhJmdUnMzlb9dJCAV40RMqIRzRSD58sTMefpavPqjHpinqAoy?= =?us-ascii?Q?meYSdBy3/SEazXQD22guca6YhvD3g59fCb/MFl5Qn7eKtzy7/kcA/qdtpdkj?= =?us-ascii?Q?B7tyBm4tsqYyRB/nkBIGZPWngiQLSQMkD9L18uYwRb6qKL88NerSFDFUFoRb?= =?us-ascii?Q?UQDcwYzryBlSpcznJmYdtCC3En8ar2KS8e9vSx4N0MXdhXCzz8K6BXBk+Jn1?= =?us-ascii?Q?DVaTCcHXX2UYTdg8nr0Qwhv5BfU73xSYiudstd4zq67bPQK6OjHsTXyt0sUD?= =?us-ascii?Q?5WSc7y0+acNrFt5lJIZdMX7sx2dSKYcQV2qccCVN5JernRHhGIvgCu1G6yEc?= =?us-ascii?Q?fIl/59gUr9Iyt9cL2vn2eS0j5l54md5wbMlwA/haCKXYFCQ6DfUS2aod+6TD?= =?us-ascii?Q?YMHesb4cu7U2ikv4d6JEQgHAVigRTW5cQdK3Cf9Ojr3hcCmDFNjauDpX5IfG?= =?us-ascii?Q?Ud9BxVpmlLMy9HGDVLgwA6L1gTETEIKOXgWRp2Nq?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 9e2061a9-582e-4a2b-70e0-08ddaf0e9b66 X-MS-Exchange-CrossTenant-AuthSource: CY8PR12MB7705.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 19 Jun 2025 08:52:23.1463 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 43083d15-7273-40c1-b7db-39efd9ccc17a X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: qpT19xq6gG1CBSGE7aOrbfKN62ad05QnoyGA0G61zhTo8vFQHzTSgJh3FjQhcxRkursHt/Ruut7JoGU5oXFE+A== X-MS-Exchange-Transport-CrossTenantHeadersStamped: SN7PR12MB7956 On Tue, Jun 17, 2025 at 11:49:20AM +0200, David Hildenbrand wrote: > On 16.06.25 13:58, Alistair Popple wrote: > > Nothing uses PFN_DEV anymore so no need to create devmap pXd's when > > mapping a PFN. Instead special mappings will be created which ensures > > vm_normal_page_pXd() will not return pages which don't have an > > associated page. This could change behaviour slightly on architectures > > where pXd_devmap() does not imply pXd_special() as the normal page > > checks would have fallen through to checking VM_PFNMAP/MIXEDMAP instead, > > which in theory at least could have returned a page. > > > > However vm_normal_page_pXd() should never have been returning pages for > > pXd_devmap() entries anyway, so anything relying on that would have been > > a bug. > > > > Signed-off-by: Alistair Popple > > > > --- > > > > Changes since v1: > > > > - New for v2 > > --- > > mm/huge_memory.c | 12 ++---------- > > 1 file changed, 2 insertions(+), 10 deletions(-) > > > > diff --git a/mm/huge_memory.c b/mm/huge_memory.c > > index b096240..6514e25 100644 > > --- a/mm/huge_memory.c > > +++ b/mm/huge_memory.c > > @@ -1415,11 +1415,7 @@ static int insert_pmd(struct vm_area_struct *vma, unsigned long addr, > > add_mm_counter(mm, mm_counter_file(fop.folio), HPAGE_PMD_NR); > > } else { > > entry = pmd_mkhuge(pfn_t_pmd(fop.pfn, prot)); > > - > > - if (pfn_t_devmap(fop.pfn)) > > - entry = pmd_mkdevmap(entry); > > - else > > - entry = pmd_mkspecial(entry); > > + entry = pmd_mkspecial(entry); > > } > > if (write) { > > entry = pmd_mkyoung(pmd_mkdirty(entry)); > > @@ -1565,11 +1561,7 @@ static void insert_pud(struct vm_area_struct *vma, unsigned long addr, > > add_mm_counter(mm, mm_counter_file(fop.folio), HPAGE_PUD_NR); > > } else { > > entry = pud_mkhuge(pfn_t_pud(fop.pfn, prot)); > > - > > - if (pfn_t_devmap(fop.pfn)) > > - entry = pud_mkdevmap(entry); > > - else > > - entry = pud_mkspecial(entry); > > + entry = pud_mkspecial(entry); > > } > > if (write) { > > entry = pud_mkyoung(pud_mkdirty(entry)); > > > Why not squash this patch into #3, and remove the pmd_special() check from > vm_normal_page_pmd() in the same go? Seems wrong to handle the PMD/PUD case > separately. Yeah, that was mostly because "someone" (and thankyou btw, it was somewhat my mess) changed all this while I was working on it :-) I wanted to make the rebase fixups obvious but will squash them for v3. > But now I am confused why some pte_devmap() checks are removed in patch #3, > while others are removed in #7. > > Why not split it up into (a) stop setting p*_devmap() and (b) remove > p*_devmap(). > > Logically makes more sense to me ... :) Heh. You're right. For various reasons this patch series has gone through a couple of reorderings, mainly to get rid of unused stuff early in the series but that didn't work out due to that RISC-V bug. I needed a break from silly rebase build errors so this was a good checkpoint. But I've reworked things for v3 to get the ordering a bit more sensible. > -- > Cheers, > > David / dhildenb >